Report-Of Committee on Chemicals and Explosives

Home , Chlorine azide, Fluorine azide, Fluorine nitrate, Fluorine perchlorate, Manganese heptoxide, Methyl azide

448 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES CE-1

Report-of Committee on Chemicals and Explosives

Correlating Committee

Dr. Robert W. Van Dolah, Chairman, Pittsburgh Mining and Safety Research Center, Bureau of Mines, U.S. Department of the Interior, 4800 Forbes Ave., Pittsburgh, PA 15213

Chester I. Babeock,~ Secretary, National Pire Protection Assn., 470 Atlantic Ave., Boston, MA 02210

W. H. Doyle, Simsbury, CT ilenry T. Rlttman, Institute of Makers of •, Thomas E. Duke, Fire Prevention & Engi- Explosives neering Bureau of Texas Richard F. Schwab, Allied Chemical Corp. Dr. Richard Y. Le Vine, Olin Corp.

tNonvoting.

Sectional Committee on Electrical Equipment in Chemical Atmospheres

Dr. Richard Y. Le Vine, Chairman, Olin Corp., 120 Long Ridge Rd., Stamford, CT 06904

Chester I. Babcock,~ Secretary, National Fire Protection Association, 470 Atlantic Ave., Boston, MA 02210

L. J. Hall. Panel No. 14, National Electrical R. F. Schwab, Morristown, NJ Code Committee W. A. Short, National Electrical-Manu- • Robert P. llowell, American Petroleu~i In" facturers Assn. stitute George O. Hunt, Jr., Manufacturing Chem- Alternates. ists' Assn. Elton L. Lltehfleld, Pittsburgh, PA F. D. Alroth. (Alternate to P. J. Schram) Frederick L. Maltby, Instrument Society W. Calder (Alternate to F. L. Maltby) of America W. H. Levers (Alternate to Robert P. C. E. Miller, Norwood, MA Howell) " Frank E. Rademacher, Chicago, IL J. Rennle (Alternate to C. E. Miller) John E. Rogerson. Cincinnati, OH Thomas S. Staron, (Alternate to Frank E. P. J. Schram, Chicago, IL Rademaehcr)

tNonvoting 449 CE-2 EXPLANATION OF REPORT

Sectional Committee on llazardous Chemical Reactions

R. F. Schwab, Chairman, Allied Chemical Corp., P.O. Box 1057R, Morristown, NJ 07960 Chester I: Babcoek,t Secretary, National Fire Protection Association, ,t70 Atlantic Ave., Boston, MA 02210

A. R. Albrecht, Midland, MI Francis W. Wischmeyer, Manufacturing Edward Cherowbrier, Prince George's Chemists' Assn. Center, Hyattsville, MD William J. Wlswesser, Fort Derrick, lloward H. Fawcett, Washington, DC Frederick, hal) Samuel A. Kaplan, New York, NY Alternates Frank O. Llndemann, Morristown, NJ James E. Collier, (Alternate to G. W. George W. Moore, Hartford, CT M oore) Dr. Robert W. Van Dolah, Pittshurgh, PA F. W. Badger, (Alternate to S. Kaplan) tNonvoting.

Sectional Committee on Properties of Ilazardous Chemicals

Thomas E. Duke, Chairman, Fire Prevention & Engineering Bureau of Texas, 1320 Mercantile Securities Bldg., Dallas, TX 75201 Chester !. Babeock,t Secretary, National Fire Protection Association, 470 Atlantic Ave., Boston, MA 02210

A. R. Albrecht, Midland, MI Ens. David A. Rltkonen, Washington, DC William J. Bradford (Mannfacturing James Saylor, American Insurance Assn. Chemists' Assn.) Norman V. Steere, Minneapolis, MN Edward Cherowbrler, Prince George's Center, Hyattsville, MD Dr. Robert W. Van Dolah° Pittslmrgh, PA R. E. Dufour, Northbrook, IL A. F. White, Conference of Special Risk R. M. Grazlano, Washington, DC George Huckeba, American Mutual In- Alternates. surance Alliance Dr. James E. Long, American Industrial Marvin W. Blaekman (.Alternate to James Hygiene Assn. Saylor) Franklin A. Miller, Rochester, NY C. W. Scbultz (Alternate to R. M. Graziano) tNonvoting. This list represents the membership at the time the Committee was balloted on the text of this edition. Since that time, changes in the membership may have occurred. The report of the Committee on Chemicals and Explosives is in three parts: Part I, prepared by the Sectional Committee on Properties of Hazardous Chemicals, proposes adoption of amendments of Haz- ardous Chemicals Data, NFPA No. 49-1973. Part I has been submitted for ballot to the Sectional Committee on Prop- erties of Hazardous Chemicals, which consists of 14 voting members, of whom all have voted affrmativel),. 450 REPORT OF COMMITTEE ON CHEMICALSAND EXPLOSIVES CE-3

Part I has also been submitted for ballot to the Correlating Committee, which consists of six voting members of whom 6 have voted affirmatively.

Part II, prepared by the Sectional Committee on Electrical Equip- ment in Chemical Atmospheres, proposes adoption of a Recom- mended Practice for Classification of Class I Hazardous Locations for Electrical Installations, NFPA No. 497-P.

Part II has been submitted for ballot to the Sectional Committee on Electrical Equipment in Chemical Atmospheres, which consists of 12 voting members, of whom 17 have voted affirmatively. One ballot was not re- turned (E. L. Litchfield).

Part II has also been submitted for ballot to the Co~relating Committee, which consists of 6 voting members, of whom 6 have voted affrmatively.

Part III, prepared by the Sectional Committee on Hazardous Chemical Reactions, proposes amendments of the Manual of Hazardous Chemical Reactions, NFPA No. 491M-1971.

Part III has been submitted for ballot to the Sectional Committee on Hazardous Chemical Reactions, which consists of 70 voting members, of whom 10 have voted affirmatively.

Part III has also been submitted for ballot to the Correlating Committee, which consists of 6 voting members, of whom all have voted affirmatively. 451 REVISIONS TO NFPA NO. 49 49-1

Part I

Proposed Amendments of Hazardous Chemicals Data

NFPA No. 49~ 1973

1. Explanatory. Insert the following statement on page ~9-7, preceding "Flammable (Explosive) Limits and Range": Control of Spillal~e and Water Pollution. Spilled chemicals and flammable liquids should not be flushed down the drain or gutter or ditch without considering the consequences. Fire fighting and some other emergency operations may require such action but flushing spilled chemicals can contaminate water supplies, cause injury, and damage property. Emphasis should be on prevention of spills and on pre-emergency planning for control of spills of materials and for control of fire fighting water contaminated with chemicals.

2. Explanatory. Add the following note to the second paragraph under "Flash Point": NOTE: There are several types of apparatus for determining flash point by test. The Tag Closed ~Iester (ASTM D56) is intended for testing liquids having a viscosity less than 45 SUS at 100 ° F. and a flash point below 200 ° F. The Pensky-Martens Closed Tester (ASTM D93) is considered accurate for testing liquids having a viscosity of 45 SUS or more at 100 ° F. or a flash point of 200 ° F. or higher. The Cleveland Open Tester (ASTM D92) is sometimes used for high flash point liquids. The Tag Open Tester (ASTM D1310) is frequently used for low-flash liquids where it is desired to have tests more representative of conditions in open tanks of flammable liquids, or for labeling and transportation purposes. For most liquids, the numerical value in degrees Fahrenheit of the closed cup flash point is some 10 to 20 percent lower than that of the open cup flash point for the same liquid, but there are some cases where the difference is greater or smaller. Standard specifications for the open cup and other testem are published by the American Society for Testing and Materials, 1916 Race St., Philadelphia, PA 19103.

3. Explanatory. Revise the first sentence under "Hazard Identi- fication System" to read: "The diamond-shaped diagram shown for each chemical gives at a glance a general idea of the inherent hazards of the chemical and the order of severity of these h~z- ards under emergency conditions such as spills, leaks and fires." 452 49-2 COMMITTEE ON CHEMICALS AND EXPLOSIVES

In the same paragraph insert the foUowing sentence between the first and second sentences: "The Hazard [dentificatio[~ System is not intended to identify the nonemergency health hazards of chemicals."

4. Explanatory. Revise the first sentence of the second paragraph under "Oxidizing Materials" to read: Because most inorganic oxidizing materials, such as sodium nitrate and potassium chlorate, do not themselves burn, their flammability hazard is zero in the diamond-shaped hazard identification symbol.

5. Aluminum (Dust or Powder). Insert between the second and third sentences in "Fire and Explosion Hazards": "Bulk dust when damp may heat spontaneously."

6. Ammonium Chloride. Add to "Fire and Explosion Hazards": "Ammonium chloride and silver salts may form a sensitive fulminating silver compound (possibly silver nitride)." Add to "Storage": "Separate from silver salts."

7. Ammonium Dichromate. In "Hazard Identification Symbol" increase Flammability Rating from 0 to I. Revise the first sentence of "Fire and Explosion Hazards" to read: "Oxidizing material, combustible solid."

8. Ammonium Nitrate. Reduce Flammability Rating from 1 to O.

9. Ammonium Perehlorale. Reduce Flammability Rating from 1 to 0 in nonfire and fire diamonds. 10. BeryUium. In "Hazard Identification Symbol" reduce Re- activity Rating from 1 to O.

11. Bronze. Delete all data on bronze.

12. Carbon Disulfide. In "Fire and Explosion Hazards" change ignition temperature to "194°F (90° C). ''

13. Dimethyl Sulfide. In "H~zard Identification Symbol" reduce Health Rating from 4 to 2. Revise "Life Hazard" to read: "Moderate eye irritant. In a fire, highly irritating sulfur dioxide will be one of the combustion products." Revise "Personal Protection" to read: "Wear self-contained breathing apparatus." 453 REVISIONS TO NFPA NO. 49 49-3

14. Lead Arsenates. Delete "Will extil~guish fire" from "Fire and Explosion Hazards."

15. Lithium Hydride. In "Hazard Identification Symbol" increase Health Rating from 1 to 3. Add "l?ersonal Protection" to read: "PERSONAL PROTECTION: Wear full protective clothing."

16. Methyl Bromide. Delete from "Fire and Explosion Hazards" the flammable limits "~13.5%" and "14.5%." Delete the last sentence from "Life Haz:~rd." Delete the second sentence from "Personal Protection."

17. Methylcyclopentane. Add to "Fire and Explosion Hazards": "Flammable limits, 1.0% and 8.4%, and Ignition temperature, 614 ° F (323 ° C)."

18. Methyl Vinyl Ketone. Increase "Health Hazard Rating" from 2 to 3. Replace the present "Life Hazard" text with the following: "Highly irritating to skin ~nd respiratory tract. Causes severe eye injury. Liquid or high concentrations of vapors causes blistering of the skin." Replace the present "Personal Protection" text with the following: "Wear full protective clothing." In first sentence of "Fire Fighting Phases" replace "explosion- resistant location" with "protected location."

19. Nitroaniline(para). In "Hazard Identification Symbol" .increase "Reactivity Rating" from 0 to 3.

20. Nitropropanes. Add a "nonfire .... Hazard Identification Symbol" with the Health, Flammability and Reactivity Ratings 1, 8, 1 respectively and replace the present "Hazard Identification Symbol" with a "fire" diamond having Health, Flammability and Reactivity Numbers 2, 8, 1. Add "Personal Protection" text to read: "In fire conditions wear self-contained breathing apparatus." Delete from "Fire ~md Explosion Hazards": "rapid heating to high temperatures may cause an explosion.

21. Potassium Chlorate. Replace present "Hazard Identification Symbol" with "nonfire" and "fire" symbol; the Health, Flam- mability and Reactivity Ratings of the nonfire symbol to be "0, O, 0," and the fire symbol to be "2, O, 0." The oxidizing agent symbol 454 49-4 COMMITTEE ON CHEMICALS AND EXPLOSIVES

"OXY" is to be shown in the fourth quadrant of each symbol. In last sentence of "Fire and Explosion Hazards" change "explode" to "rupture."

22. Sodium Cyanide and Potassium Cyattidc. Add to "Personal Protection": "Upon any contact with skin or cycs, the materials should be washed off immediately. Remove contaminated clothing."

23. Sodium Dichloro-s-Triazinetrione. In "Life Hazard" change "contact with water" to "contact with small amounts of water."

24. Sulfur Dioxide. In "Hazard Identification Symbol" reduce Health Rating from 3 to 2.

25. Tetraethyl Lead; Tetramelhyl Lead. Delete all data and refer to Motor Fuel Antiknock Compound (conlaining lead).

26. Appendix. Replace the present Appendix A with the following:

APPENDIX A

1. The information preceding this Appendix is restricted to chemicals that have a He-~lth Hazard Identification number of 2 or higher, a Reactivity Hazard Ideutific~ttion number of 1 or higher, present unusual storage o1" fire fighting problcms, or can become hazardous on being contaminated or mixed with other chemicals (sce page 49-3). Since these limitations exclude many chcmicals that are hazardous primarily because of flammability, i.e., acetone, the Sectional Committee on Properties of Hazardous Chemicals, at the request of many users of this pamphlet, has added this Appendix so that one can now find in one pamphlet guidance on handling emergencies involving the more common flammable chemicals commercially available. 2.-Recommendations for handling emergencies involving a chemical that is hazardous primarily because of flammability depend on its physical state (liquid, gas), its flash point, and its water solubility. The numbers in the righthand column of Table 1 refer to numbered paragraphs at the end of the Table that contain recommendations for fighting fires or handling spills. NFPA No. 325M, Fire-Hazard Properties of Flammable Liquids, Gases and Volatile Solids, contains these and other data on more than 1,300 chemicals. 455 REVISIONS TO NFPA NO. 49 49-5

Table 1. Properties of Common Flammable Chemicals Hazard Identification Fire Flare- Reac- Flash Pt. Water Fighting Health mability tlvity °F Soluble Phases Acetophenone 1 2 0 180 (oc) No 5 Acetone 1 3 0 0 Yes 2 Adipic Acid 1 1 0 385 No 7 Amyl Acetate (n) 1 3 0 77 Slightly 2 Amyl Alcohol (pri. n) 1 3 0 91 Slightly 2 Amyl Alcohol (sec. n) 1 3 0 94 Slightly 2 Amyi Alcohol (iso) 1 2 0 109 Slightly 3 Amyl Alcohol (sec. iso) 1 2 0 103 Slightly 3 Amylbenzene 1 2 0 150 (oc) No 5 Amyl Bromide 1 3 0 90 No 4 Amyl Chloride(n) 1 3 0 55 (oc) No 4 Amyl Laurate 0 1 0 300 (oc) No 7 Amylnaphthalene 0 1 0 255 (oc) No 7 Asphalt (typical) 0 1 0 400 + (oc) 'No 7 Butane 1 4 0 Gas No 1 Butenes 1 4 0 Gas No 1 Butyl Acetate 1 3 0 72 Slightly 2 Butyl Acetate (iso) 1 3 0 64 No 4 Butyl Alcohol (n) 1 3 0 84 Yes 2 sec-Butyl Alcohol 1 3 0 75 Yes 2 ter t-Butyl Alcohol 1 3 0 52 Yes 2 Butyl Benzoate (n) 1 1 0 225 (oc) No 7 Chlorohexane 0 3 0 95 No 4 Cod Liver Oil 0 1 0 412 No 7 Corn Oil 0 1 0 490 No 7 Cottonseed Oil 0 1 0 486 No 7 Cyclohexane 1 3 0 minus 4 No 4 Cyclohexanone 1 2 0 111 Slightly 3 Cyclohexyl Alcohol 1 2 0 154 Slightly 3 Cyclopcntane 1 3 0 less than 20 No 4 Cyclopropane 1 4 0 Gas No 1 Decane (n) 0 2 0 115 No 5 Decanol 0 2 0 180 No 5 Dibutyl Phthalate 0 1 0 315 No 7 Diesel Fuel Oil No. 1-D 0 2 0 100 rain. or legal No 5 Diesel Fuel Oil No. 2-D 0 2 0 125 rain. or legal No 5 Diesel Fuel Oil No. 4-D 0 2 0 130 min. or legal No 5 Diethanolamine 1 1 0 305 Yes 6 Diethylcne Glycol 1 1 0 .225 Yes 6 Diethyl Phthalate (o) 0 1 0 325 (oc) No 7 Dioctyl Phthalate 0 1 0 425 (oc) No 7 Dipropylene Glycol 0 1 0 280 Yes 6 Ethyl Acetate 1 3 0 24 Sightly 2 Ethyl Alcohol 0 3 0 55 ~es 2 Ethyl Benzoate 1 1 0 greater than 204 No 7 Ethylbutyl Acetate 1 2 0 130 (oc) No 5 Ethylbutyl Alcohol 1 2 0 ' 135 (oc) No 5 Ethylbutyl Ketone 1 2 0 115 (oc) No 5 Ethylene Glycol 1 1 0 232 Yes 6 FuelOil No. 1 (Range Oil, Kerosine) 0 2 0 100 rain. or legal No 5 Fuel Oil No. 2 0 2 0 I00 rain. or legal No 5 Fuel Oil No. 4 0 2 0 130 rain. • or legal No 5 Fuel Oil No. 5 0 2 0 130 rain. or legal No 5 Fuel Oil No. 6 0 2 0 150 min. or legal No 5 Gasoline 1 3 0 minus 45 No 4 456 49-6 COMMITTEE ON CHEMICALS AND EXPLOSIVES

Table 1. Properties of Common Flammable Chemicals -- (cont.) Hazard Identification Fire Flare- Rest- Flash Pt. Water Fighting Health mabllity tivlty °F Soluble Phases Glycerine 1 1 0 320 Yes 6 Heptane (n) 1 3 0 25 No 4 Hexane (n) 1 3 0 minus 7 No 4 Hexyl Alcohol 1 2 0 145 Slightly 3 Hydrogen 0 4 0 Gas Slightly 1 Isopropyl Alcohol 1 3 0 53 Yes 2 Lanolin 0 1 0 460 No 7 Lard Oil (commercial or animal) 0 1 0 395 No 7 Linseed Oil (boiled) 0 1 0 403 No 7 Lubricating Oil (mineral) 0 1 0 300-450 No 7 Methyl Acetate 1 3 0 14 Yes 2 Methyl Alcohol 1 3 0 52 Yes 2 Methyl Ethyl Ketone 1 3 0 21 Yes 2 Methyl Salieylate 1 1 0 214 No 7 Mineral Oil 0 1 0 380 (oc) No 7 Octane 0 3 0 56 No 4 Octyl Alcohol (n) 1 2 0 178 No 5 Oleic Acid 0 1 0 372 No 7 0leo Oil 0 1 0 450 No 7 Peanut Oil 0 1 0 540 No 7 Pentane 1 4 0 Less than minus 40 No 1 Pentanol-3 1 2 0 105 Slightly 3 Petroleum (crude) 1 3 0 20-90 No 4 Propane 1 4 0 Gas No 1 Propyl Acetate 1 3 0 58 Yes 2 Propylene Glycol 0 1 0 210 Yes 6 Quenching Oil 0 1 0 365 No 1 Soy Bean Oil 0 1 0 540 No 7 Tallow 0il 0 1 0 492 No 7 Tetrahydronapht halene 1 2 0 160 No 5 Transformer Oil 0 1 0 295 (oc) No 7 2, 4, 5-Triehlorophenol in solvent 1 1 0 Solvent Flash Point No 5 2, 4, 6-Trichlorophenol in solvent 1 1 0 Solvent Flash Point No 5 Triethylene Glycol 1 1 0 350 Yes 6 Turpentine 1 3 0 95 No 4 Vegetable Oil (hydrogenated) 0 1 0 610 (oc) No 7

Fire Fighting Phases The numbers at the left of the paragraphs below correspond to the numbers in the right-hand column of Table 1.

1 FIRE FIGHTING PHASES: Stop flow of gas. Use water to keep fire- exposed containers cool and to protect men effecting the shutoff. If a leak or spill has not ignited, use water spray to disperse the gas or vapor and to protect men attempting to stop a leak.

2 FIRE F10~TISG PHASES: Use dry chemical, "alcohol" foam, or carbon dioxide; water may be ineffective (see Explanatory), but water should be used to keep fire-exposed containers cool. If a leak or spill has not ignited, use water spray to disperse the vapors and to protect men • attempting to stop a leak. Water spray may be used to flush spills away from exposures and to dilute spills to nonflammable mixtures. 457 REVISIONS TO NFPA NO. 49 49-7

3 FIRE FIGHTING PHASES: Use water spray, dry chemical, "alcohol" foam, or carbon dioxide. Use water to keep fire-exposed containers cool. If a leak or spill has not ignited, use water spray to disperse the vapors and to protect men attempting to stop a leak. Water spray may be tused to flush spills away from exposures and to dilute spills to nonflammable mixtures.

4 FIRE FIGHTING PHASES: Use dry chemical, foam, or carbon dioxide. Water may be ineffective (see Explanatory), but water should be used to keep fire-exposed containers cool. If a leak or spill has not ignited, use.water spray to disperse the vapors and to protect men attempting to stop a leak. Water spray may be used to flush spills away from exposures.

5 FIRE FIGHTING PHASES: Use water spray, dry chemical, foam, or carbon dioxide. Use water to keep fire-exposed containers cool. If a leak or spill has not ignited, use water spray to disperse the vapors and to provide protection for men attempting to stop a leak. Water spray may be used to flush spills away from exposures.

6 FIRE FIGHTING PHASES: Use water spray, dry chemical, "alcohol" foam, or carbon dioxide. Water or foam may cause frothing. Use water to keep fire-exposed containers cool. Water spray may be used to flush spills away from exposures and to dilute spills to noncombustible mixtures.

7 FIRE FIGHTING PHASES: Use water spray, dry chemical, foam, or carbon dioxide. Water or foam may cause frothing. Use water to" keep fire-exposed containers cool. Water spray may be used to flush spills away from exposures.

27. New Data. Insert data on 29 chemicals as follows:

AMMONIUM PERMANGANATENH4MnO4 "(~ (~

DESCRIPTION: Crystalline solid; violet Nonfire Fire brown or dark purple. FIRE AND EXPLOSION HAZARDS: Powerful oxidizing agent. May become shock-sens{tive ~t 140°F (60 ° C) and m~y explode when exposed to higher temperatures. Spontaneous chemical reaction, ignition or explosion m~y occur if mixed with readily oxidizable, organic or f]nmmable materi~ls. LIFE HAZARD: Skin and eye irritant; avoid breathing dust. When heated to decomposition yields toxic fumes. PERSONAL PROTECTION: In fire' conditions wear self-contained breathing apparatus. 458 i 49-8 COMMITTEE ON CHEMICALS AND EXPLOSIVES

FIRE FIGHTING PHASES: Fight fires from an explosion-resistant location. Use water from unmanned monitors or hoseholders to keep fire-exposed containers cool. USUAL SHIPPING CONTAINERS: Metal barrels or drums. STORAGE: Protect against physical damage. Separate from combustible, organic or other readily oxidizable materials. Im- mediately remove and dispose of any spilled permanganate.

ANTIMONY PENTAFLUORIDE SbF5 DESCRIPTION: Oily, colorless liquid. FIRE AND EXPLOSION HAZARDS: Noncombustible. Reacts with water and moisture to form hydrofluoric acid. LIFE HAZARD: Antimony pentafluoride and its decomposition products are irritating to eyes, skin and mucous membranes. Liquid can cause skin burns. PERSONAL PROTECTION: Wear full protective clothing. FIRE FIGHTING PHASES: Water may be used to fight fires in the vicinity of antimony pentafluoride. Flood spills with large volumes of water. USUAL SHIPPING CONTAINERS: Stainless steel containers. STORAGE: Protect against physical damage. Store in a dry, well-ventilated area away from combustible materials. Out- side or detached storage is preferred.

ARSENIC CHLORIDE AsC13 DESCRIPTION: Colorless liquid, fumes in air, releasing hydrogen chloride. FIRE, AND EXPLOSION HAZARDS: Noncombustible. LIFE HAZARD: Very toxic; eye, skin and respiratory irritant. Contact with water produces hydrogen chloride. PERSONAL PROTECTION: Wear full protective clothing. FIRE FIGHTING PHASES: Use water spray, dry chemical, foam, or carbon dioxide for fighting fires in areas where arsenic chloride is exposed. USUAL SHIPPING CONTAINERS: Glass bottles, cans, drums. STORAGE: Protect against physical damage. Store in a cool, dry location. 459 REVISIONS TO NFPA NO. 49 49-9

ARSENIC TRISULFIDE As2S~ ~ DESCRIPTION: Yellow or rcd crystals. Nonfire Fire FIRE AND EXPLOSION HAZARDS: ConIbustible. Yields flammable hydrogen sulfide on contact with strong acids. Reacts vigorously with oxidizing agents. LIFE HAZARD: Arsenic trisulfide is a poison. Poisoning may occur by ingestion or inhalation of dust. Skin contact may produce dermatitis. When heated to decomposition or upon contact with acids, arsenic trisulfide decomposes to produce extremely toxic arsine and hydrogen sulfide. PERSONAL PROTECTION: Wear self-contained breathing apparatus. FIRE FIGHTING PHASES: Water may be used to fight a fire in an area containing arsenic trisulfide. USUAL SHIPPING CONTAINERS: Barrels, bags and other containers authorized by DOT for a Class B poisonous solid. STORAGE: Protect against physical damage. Separate from food, oxidizing agents and acids.

CALCIUM CHLORATE Ca(C103)2 2H20 ~ DESCRIPTION: White to yellowish deli- quescent crystals. Nonfire Fire FIRE AND EXPLOSION HAZARDS: Powerful oxidizing material. Forms explosive mixtures with combustible, organic o1" other easily oxidizable materials. These mixtures are easily ignited by friction or heat. Containers may rupture when involved in fire.. LIFE HAZARD: Yields toxic fumes when involved in fire. PERSONAL PROTECTION: In fire conditions wear self-contained breathing apparatus. FIRE FIGHTING PHASES: Flood with water. USUAL SHIPPING CONTAINERS: Glass bottles, metal cans or drums. STORAGE: Protect against physical damage. Separate from combustible, organic, or other readily oxidizable materials, 460 49-10 COMMITTEE ON CHEMICALS AND EXPLOSIVES

acids, ammonium salts, sulfur, and flammable vapors. Avoid storage on wooden floors, hnmediately remove and dispose of any spilled chlorate. Rm~AaKS: See Code for the Storage of Liquid and Solid Oxidizing Materials (NFPA No. 43'A).

CHROMYL CHLORIDE Cr02CI~ Q/~/?~ DESCRIPTION: Dark red fuming liquid. FIB.E AND EXPLOSION HAZARDS: Noncombustible. Reacts vigorously with water, forming chromic acid, chromic chloride, hydrochloric acid and chlorine. Causes ignition of ammonia, ethyl alcohol or turpentine. ]~'IFE HAZARD: Toxic. Liquid is corrosive to tissue. Vapor is a severe irritant to eyes and respiratory system. Prolonged or excessive exposure could be fatal. PERSONAL PROTECTION: Wear full protective clothing. FIRE FIGHTING PHASES: Use ample volumes of water and ~se water spray if necessary to keep containers cool. Flood spills with large volumes of water. SHIPPING CONTAINERS: One-gallon bottles; 85- and 200-pound drums. STORAGE: Protect against physical damage. Store in dry, well- ventilated area, away from ammonia, alcohol, turpentine or other combustible materials. Outside or detached storage is preferable. REMARKS: See Manual of Hazardous Chemical Reactions (NFPA No. 491M).

CUMENE C6HsCH(CH3)~ @~ DESCRIPTION: Colorless liquid. FIRE AND EXPLOSION HAZARDS: Flammable liquid. Vapor forms explosive mixtures with air. Flammable limits: 0.9% and 6.5%. Flash point, 96 ° F (36 ° C). Ignition temperature, 797 ° F (425 ° C). Liquid is lighter than water (specific gravity, 0.9). Vapor is heavier than air (vapor-air density at 100°F (37.8 ° C), 1.3) and may travel a considerable distance to a source of ignition and flash back. Not soluble in water. 461

REVISIONS TO NFPA NO. 49 49-11

LIFE HAZARD: Eye add skin irritant. Inhalation of high concentrations of vapors causes narcosis. PERSONAL PROTECTION: Wear self-contained breathing apparatus. FIRE FIGHTING PHASES: Use water spray, dry chemical, foam, or carbon dioxide. Use water to keep fire-exposed containers cool. Water spray may be ineffective as an extinguishing agent (see Explanatory). Direot hose streams from a protected location. If a leak or spill has not ignited, use water spray to disperse the vapors anal to protect men attempting to stop a leak. Water spray may be used to flush spills away from exposures. USUAL SHIPPING CONTAINERS: Drums, tank cars, tank trucks. STORAGE: Protect against physical damage. Separate from oxidizing materials. Outside or detached storage is preferred. Inside storage should be in a standard flammable liquids storage room. REMARKS: Electrical installations in Class I hazardous locations as defined in Article 500 of the National Electrical Code should be in accordance with Article 501 of the Code; and electrical equipment should be suitable for use in atmospheres containing cumene vapors.

DICHLOROETHYL ETHER CICH2CH20CH~CH2C1 DESCRIPTION: Colorless clear liquid with odor like ethylene dichloride. FIRE AND EXPLOSION HAZARDS: Combustible liquid. Vapor forms explosive mixtures with air. Flammable limits not reported. Flash point, 131 ° F (55 ° C). Ignition temperature, 696 ° F (369 ° C). Liquid is heavier than water-(specific gravity, 1.2). Not soluble in water. LIFE HAZARD: Toxic by inhalation or oral intake. Strong eye, skin and respiratory irritant. Absorbed by skin. Prolonged, excessive, or repeated exposures in any form are hazardous. Decomposes when heated to form toxic and irritating decomposition products. PERSONAL PROTECTION: Wear full protective clothing. 462 49-12 COMMITTEE ON CHEMICALS AND EXPLOSIVES

FIRE F1GHTING PtIASES: Use water spryly, dry chemical, foam, or carbon dioxide. When using water to keep fire-exposed containers cool, direct hose streams from a protected location. if a le:d¢ or spill has not ignited, use w:~ter spnty to disperse the vapors and to protect men attempting to stop ~ leak. Water spr'xy may be used to flush spills aw~y from exposures. Water may be used to blanket fire. USUAL SHIPPING CONTAINERS: Gh~ss bottles, drums, tank cars, tank trucks, tank barges. STORAGE: Protect against physical damage. Separate from other storage. Outside or detached storage is preferred. Inside storage should be in a standard flammable liquids storage room. REMARKS: See Flammable and Combustible Liquids Code (NFPA No. 30).

1, 3-DICHLOROPROPENE (cis and trans) CHCI:CHCH2C1 DESCRIPTION: Both isomers are colorless liquids with chloroform-like odors. FI I~E AND EXPLOSION H A,ZA liDS : Flammable liq uids. Vapors form explosive mixtures with air. Flammable limits, 5.3% and 14.5%. Flash point, 95 ° F (oc) (35 ° C). Ignition temperature not reported. Liquids are heavier than water (specific gravity, 1:2). Not soluble in water. Vapor is heavier than air (vapor- air density at 100°F (37.8 ° C), 1.4) and may travel a considerable distance to a source of ignition and flash back. LIFE HAZAitD: Toxic by inhalation or oral intake. Strong eye, skin and respiratory irrit~nt. Prolonged, excessive, or repeated exposures in any form are hazardous. Decomposes when heated to form toxic arid irritating decomposition products. PERSONAL PROTECTION: Wear full protective clothing. FlllE FIGHTING PHASES: Use water spray, dry chemical, foam, or carbon dioxide. Use water to keep fire-exposed containers cool. Water spryly may be ineffective as an extinguishing agent (see Explanatory). Direct hose streams from a protected location. If a leak or spill has not ignited, use water spray to disperse the vapors and to protect men attempting to stop a leak. Water spray may be used to flush spills away from exposures. Water may be used to blanket fire. 463 REVISIONS TO NFPA NO. 49 49-1.3

UsuAL SHIPPING CONTAINERS: Tank ships, barges. STOaAGE: Protect against physical damage. Separate from other storage. Outside or detached storage is. preferred. Inside storage should be in a st'~ndard flammable liquids storage room. REMARKS: Electrical installations in Class I hazardous locations as defined in Article 500 of the National Electrical Code should be in accordance with Article 501 of the Code; and electrical equipment should be suitable for use in atmospheres containing I, 3-dichloropropene vapors. See Flammable and Com- bustible Liquids Code (NFPA No. 30), and Fire-Hazard Properties of Flammable .Liquids, Gases and Volatile Solids (NFPA No. 325M).

DIMETHYL ETHER CH~OCH~ /~ DESCRIPTION: Colorless gas with an ethereal odor. Liqiaid below minus 11°F (minus 23.9 ° C). FIRE AND EXPLOSION HAZAIH)S: Flammable gas. Forms explosive mixtures with air. Flammable limits, 3.4% and 270-/0. Ignition tempcrature, 662 ° F (350 ° C). Vapor is heavier than air (vapor density, 1.6). Prcsence of oxygen, long standing, or exposure in bottles to sunlight m-~y result in formation of unstable peroxides which may explode spontaneously or when heated. Soluble in water. LIFE HAZARD: Gas possegses irritative and narcotic properties. Absorption of excessive quantities by inhalation and skin may lead progressively to a state of intoxication~ loss of consciousness and death due to respiratory failure. PERSONAL PROTECTION: Wear 'self-contained breathing apparatus. FIRE FIGHTING PHASES: Stop flow of gas. Use water to keep fire-exposed containers cool. and to protect men effecting the shutoff. USUAL SHIPPING CONTAINERS: 25-, 50-, 100- and 150-pour/d cylinders. STOI~.AGE: Protect against physical damage. Outside or detached storage is preferred. Inside storage should be in cool, well- ventilated, noncombustible location aw-~y from all possible sources of ignition. 464 49-14 COMMITTEE ON CHEMICALS AND EXPLOSIVES

RE.~IARKS: Electrical installations in Class I hazardous loc'~tions as defined in Article 500 of the National Electrical Code shoul:l be in accordance with Article 50I of the Code; and electrical equipment should be suitable for use in atmospheres containing dimethyl e~er wtpors. See National Elect~rical Code (NFPA No. 70), Fire-Hazard Properties of Flammable Liquids, Gases and Volatile Solids (NFPA No. 325M), and Manual of Hazardous Chemical Reactions (NFPA No. 491M).

HYDRIODIC ACID HI DESCRIPTION: Clear or pale.yellow solution of hydro- gun iodide in water, containing 57% hydrogen iodide.

FIRE AND EXPLOSION HAZARD: Noncombustible. Soluble in water. LIFE HAZARD: Toxic and strong irritant. PERSONAL PROTECTION: Wear full protective clothing. FInE FIGHTING PHASES: Use water on fires in which hydriodic acid is involved. Neutralize with chemically basic substances such as sodium bicarbonate, soda ash, or slaked lime.

USUAL SHIPPING CONTAINERS: Glass, earthenware bottles. STORAGE: Protect against physical damage. ,~

ISOPROPYLAMINE (CH~)2CH'NH2 DESCRIPTION: Colorless liquid below 90°F (32 ° C), ammoniacal odor. FInE AND EXPLOSION HAZARDS: Flammable liquid. Flash point, below 0°F (minus 18 ° C). Reacts vigorously with oxidizing materials. Autoignition temperature, 756 ° F (402 ° C). Vapor is heavier than air (vapor density, 2.03) and may travel considerable distance to ignition source and flash back. Soluble ill water. LIFE HAZARD: Strong eye, skin and respiratory irritant. PERSONAL PROTECTION: Wear full protective clothing. 465 REVISIONS TO NFPA NO. 49 49-15

FIRE FIGHTING PHASES: Use water spray, dry chemical, "alcohol" foam, or carbon dioxide. Use water to keep fire-exposed con- tanners cool. Water spray may be ineffective as an extinguishing agent (see Explanatory). Direct hose streams from a protected location. If a leak or spill has not ignited, use water spray to disperse the vapors and to protect men attempting to stop a leak. Water spray may be used to flush spills away from exposures and to dilute spills to nonflammable mixtures. USUAL SHIPPING CONTAINERS: Glass bottles, metal cans, drums. STORAGE: Protect against physical damage. Separate from other storage. Outside or detached storage is preferred. Inside storage should be in a standard flammable liquids storage room.

A MERCURIC CYANIDE Hg(CN)2 (3XO) DESCRIPTION; White crystalline solid; odorless. FIRE AND EXPLOSION HAZARDS: Noncombustible but when , heated to decomposition, or on contact with acid, it releases flammable hydrogen cyanide. Not soluble in cold water. LIFE HAZARD: Extremely toxic. Heating to decomposition or contact with acids releases highly toxic hydrogen cyanide (see Hydrogen Cyanide) and mercury vapor. PERSONAL PROTECTION: Wear full protective clothing. Upon any contact with skin or eyes, material should be washed off immediately. Remove contaminated clothing. FIRE FIGHTING PHASES: Approach fire from upwind. Water or other extinguishing agent suitable for use on burning material may be used to fight a fire in an area containing mercuric cyanide.

USUAL SHIPPING CONTAINERS: Wooden boxes or fiberboard boxes with metal inside containers, not over 25 pounds capacity each; glass bottles not over 5 pounds capacity each; metal barrels or drums; fiberboard boxes with a tightly closed polyethylene or other equally efficient plastic liner. STORAGE: Protect against physical damage. Outside or detached isolated storage is preferred. Inside storage should be in a cool, well-ventilated, noncombustible location, away from all possible sources of ignition. Always keep container closed. 466 49-16 COMMITTEE ON CHEMICALS AND EXPLOSIVES

2-METHYLBUTYRALDEHYDE CH3CH2CH(CH3) CHO

DESCRIPTION: Colorless liquid.

FIRE AND EXPLOSION HAZAm)S: Flammablc liquid. Vapor forms explosive mixtures with air. Flammable limits not reported. Flash point, 49°F (oc) (9 ° C). Liquid is lighter than water (specific gravity, 0.8). Vapor is heavier than air (vapor-air density at 77 ° F (25 ° C) is 1.1) and may travel a considerable distance to a source of ignition and flash back. Not soluble in water.

LIFE HAZARD : Vapors are a severe irritant to the eyes and mucous membranes. In high concentrations vapors will cause nausea and may be toxic.

PERSONAL PROTECTION: Wear self-contained breathing apparatus.

FIRE FIGHTING PHASE: Use water spray, dry chemical, foam, or ' carbon dioxide. Use water to keep fire-exposed containers cool. Water spray may be ineffective as an extinguishing agent (see Explanatory). Direct hose streams from a protected location. If a leak or spill has not ignited, use water spray to disperse the vapors and to protect men attempting to stop a leak. Water spray may be used to flush spills away from exposures.

USUAL SHIPPING CONTAINERS: Tank barges, drums, tank cars, tank trucks, and portable tanks. (Drums to 55-gallons and tanks to 20,000 pounds gross.)

STORAGE: Protect against physical damage. Separate from oxidizing materials. Outside or detached storage is preferred. Inside storage should be in a standard flammable liquid storage room.

'REMARKS: Electrical installations in Class I hazardous locations as defined in Article 500 of the National Electrical Code should be in accordance with Article 501 of the Code; and electrical equipment should be suitable for use in atmospheres containing 2-methylbutyraldehyde vapors. 467 REVISIONS TO NFPA NO. 49 49-17

MONO-(TRICHLORO) TETRA (MONOPOTASSIUM DICHLORO)-PENTA-s-TRIAZINE-TRIONE C3C13N303 • 4KC12(NCO) a /N/~

DESCRIPTION: White crystalline solid with strong chlorine odor.

FIRE AND EXPLOSION HAZARDS: Oxidizing and chlorinating agent. Contact with most foreign materials, organic matter or easily chlorinated or oxidized materials may result in fire. Contact with ammonia, ammonium salts, urea or similar compounds which contain nitrogen may form nitrogen trichloride, a highly explosive compound. Mixture with hydrated salts may result in an exothermie reaction, decomposition and container rupture due to pressure. Mixture with non-ionic surface- active agents may result in highly exothermic reactions causing fire or explosion. Decomposition can be initiated with a heat source and can propagate throughout the mass with evolution of extremely dense and noxious fumes.

LIFE HAZARD: The solid material is itself highly irritating to skin, eyes and respiratory tract, and in a fire, as a result of decomposition or contact with small amounts of water, chlorine and other toxic gases will be evolved.

PERSONAL PROTECTION: Wear full protective clothing. .|. 'F'IRE FIGHTING PHASES: Use water spray to cool containers ex- "~ posed to fire and massive quantities of water to dilute material involved in a fire or spilled from containers.

USUAL SHIPPING CONTAINERS: Moisture-excluding fiber drums with polyethylene bag liner, and lined pails. Smaller quantities are packaged in glass or polyethylene bottles and in foil or polyethylene laminated packets.

STORAGE: Protect against physical damage. Store in cool, dry, well-ventilated place away from flammable liquids, combustible materials, and oxidizable materials. Drums may rupture if the contents are exposed to heat or become contaminated or wet. Drums should be palletized to prevent wetting from floor washings or drainage. Avoid prolonged storage in unventilated areas at summer temperatures. REMARKS: See Code for the Storage of Liquid and Solid Oxidiz- ing Materials (NFPA No. 43A). 468 49-18 COMMITTEE ON CHEMICALS AND EXPLOSIVES

MOTOR FUEL ANTIKNOCK COMPOUNDS (Contain lead) DESCRIPTION: Red, orange or blue (dyed) liquids with sweet musty odor. Comprise a range of mixtures of tetraethyl lead (TEL), tetramethyl lead (TML), methylethyl lead (MEL), ethylene dibromide, ethylene dichloride, solvent, antioxidant, dye and inerts. FIRE AND EXPLOSION HAZARDS: Flammable or combustible liquids. Flash points range from 89 ° F (oc) (32 ° C) to 265 ° F (oc) (130 ° C). Specific gravity, greater than 1. Not soluble in water. Thermal decomposition may occur above 212°F (100 ° C), With TML compounds thermal decomposition is more likely to take the form of decomposition of vapors at the surface; with TEL compounds it is more likely to be in the form of homogeneous bulk decomposition. Both types of decomposition are considered hazardous and in either case rapid decomposition will cause container explosion. LIFE HAZ.~RD: Vapors are very toxic. Fatal lead poisoning may occur by ingestion, vapor inhalation or skin absorption. PERSONAL PROTECTION! Wear full protective clothing. FIRE FIGHTING PHASES: Fight fires from an explosion-resistant location. Use water from unmanned monitors and hoseholders to keep fire-exposed containers cool. On fires in which containers are not exposed, use water spray, dry chemical, foam, or carbon dioxide. If a leak or spill has not ignited, use water spray to disperse vapors. If it is necessary to stop a leak, use water spray to protect men attempting to do so. Water spray may be used to flush spills away from exposures. USUAL SHIPPING CONTAINERS: Metal cans in wooden 'boxes, metal drums, cylinders, tanks, tank cars, tank trucks, tank barges. STORAGE: Protect against physical damage. Store in a cool, isolated, well-ventilated area. Keep away from fire, heat and strong oxidizing agents. Tanks should be stored in a sprinklered area. REMARKS: Electrical instMlations in Class I hazardous locations as defined in Article 500 of the National Electrical Code should be in accordance with Article 501 of the Code; and electrical equipment should be suitable for use in atmospheres containing vapors of the antiknock compound. See Flammable and 469 REVISIONS TO NFPA NO. 49 49-19

Combustible Liquids Code (NFPA No. 30), National Electrical Code (NFPA No. 70), Static Electricity (NFPA No. 77), and Fire Hazard Properties of Flammable Liquids, Gases and Volatile Solids (NFPA No. 325M).

NICKEL CARBONYL Ni(CO)~ /Q/~ DESCRIPTION: Colorless volatile liquid, below 109.4° F (43 ° C). FIRE AND EXPLOSION HAZARDS: Flammable liquid that rapidly volatilizes at room temperature. Vapor forms explosive mixtures with air. Flammable limits, lower 2%, upper not known. Flash point, less than minus 4°F (minus 18 ° C). Vapor is heavier than air and may travel a considerable distance to a source of ignition and flash back. Liquid may explode when heated under confinement. Not soluble in water. LIFE HAZARD: Extremely toxic by inhalation and ingestion. A few breaths could be fatal. PERSONAL PROTECTION: Wear full protective clothing. F, IRE FIGHTING PHASES: Use water, foam, carbon dioxide, dry chemical. ~SUAL SHIPPING CONTAINERS: Compressed gas cylinders. STORAGE: Protect against physical damage. Separate from other storage. Outside or detached storage is preferred. RE,lARKS: See Manual of Hazardous Chemical Reactions (NFPA No. 491M) and Fire Hazard Properties of Flammable Liquids, Gases and Volatile Solids (NFPA No. 325M).

NITROGEN TRIOXIDE N_2.0~ DESCRIPTION: Blue liquid with a boiling point of 38 ° F (3 ° C). Dissociates upon vaporization producing primarily nitric oxide and nitrogen dioxide. FIRE AND EXPLOSION HAZARDS: Noncombustible but a strong. oxidizing agent that may cause fire on contact with combustible materials. 470 49-20 COMMITTEE ON CHEMICALS AND EXPLOSIVES

LIFE HAZARI): Vapors are extrenicly irritating to the respiratory tract and may cause fatal pulmonary edenla. Syinptoms m:~y be delayed for several hours. Vapors may cause severe eye burns. Liquid is corrosive to the eyes and skin.

PERSONAL PROTECTION: Wear full protective clothing.

FIRE FIGHTING PHASES: Stop flow of gas. Use water to keep fire- exposed containers cool and to protect men effecting the shutoff.

USUAL SHIPPING CONTAINERS: Special steel cylinders.

STORAGE: Protect against physical dmnage. Outside or detached storage is preferred. Inside storage should be in a cool, well-ventilated, noncombustible location, away from all possible sources of ignition.

POTASSIUM BROMATE KBr0~

DESCRIPTION: White crystals or powder.

FIRE AND EXPLOSION HAZARDS: Noncombustible. Powerful oxidizing material. Forms explosive mixtures with combustible, org~mic or other easily oxidizable materiMs. These mixtures are easily ignited by friction or heat. Containers may rupture when involved in a fire.

LIFE HAZARD: Moderately hazardous to health.

FIRE FIGHTING PHASES: Flood with water.

USUAL SHIPPING CONTAINERS: Glass jars, fiber or wooden containers with metal liners, steel drums.

STORAGE: Protect against physical damage. Isolate from combustible, organic or other readily oxidizable-materials. Avoid storage on wood floors, lmmedistely remove and dispose of any spilled bromate.

REMARKS:See Code for the Storage of Liquid and Solid Oxidizing Materials (NFPA No. 43A). 471 REVISIONS TO NFPA NO, 49 49-21

SODIUM DICHLORO-s-TRIAZINE TRIONE- DIHYDRATE NaC12(NC0)3.2H~O /%/~ DESCRIPTION: White, crystalline solid with chlorine odor. FIRE AND EXPLOSION HAZARDS: Oxidizing and chlorinating agent. Contact with some foreign materials or organic matter or easily chlorinated or oxidized materiMs may result in fire. Contact with ammonia, ammonium salts, urea or similar compounds that contain nitrogen may form nitrogen tri- chloridc, a highly explosive compound. Mixture with hydrated salts may result in an exothermic reaction and decomposition. Mixture with non-ionic surface-active agents may result in • exothermic reactions causing fire. Difficult to ignite but, once iaitiated, decomposition can propagate slowly throughout the mass, with evolution of extremely dense and noxious fumes. LIFE HAZARD: The solid material is itself highly irritating to skin, eyes and,respiratory tract, and in a fire, as a result of decomposition or contact with small amounts of water, extremely dense and noxious fumes containing chlorine and other toxic gases will be evolved. PERSONAL PROTECTION: Wear full protective clothing. FIRE FIGHTING PHASES: Use water spray to cool containers exposed to fire and massive quantities of water to dilute material involved in a fire or spilled from containers. USUAL SHIPPING CONTAINERS: Moisture-excluding fiber drums with polyethylene bag liner, and lined pails. Smaller quantities are packaged in glass or polyethylene bottles and in foil or polyethylene laminated packets.. STORAGE: Protect against physical damage. Store in cool, dry, well-ventilated place away from flammable liquids, combustible materials, and oxidizable materials. Drums may rupture if the contents are exposed to heat or become contaminated or wet. Drums.should be palletized to prevent wetting from floor washings or drainage. Avoid prolonged storage in unventilated areas at summer temperatures.

SODIUM HYDRIDE Nail DESCRIPTION: Silvery needles turning off-white on exposure to air. Sometimes furnished as a finely ground slurry in oil containing 25 to 50% sodium hydride. 472 49-22 COMMITTEE ON CHEMI'CALS AND EXPLOSIVES

FIRE AND EXPLOSION HAZARDS: Flammable solid. May ignite spontaneously on exposure to moist air. On heating or in contact with moisture or acids, an exothermic reaction may be sufficient to c'~use ignition. Violently reactive with strong oxidizers. Can form dust clouds that may explode on contact with flame, heat, or oxidizing materials.

LIFE HAZARD: Highly corrosive on inh-dation, ingestion, or contact with skin. On contact with moisture or water, sodium hydride yields sodium hydroxide which is very corrosive.

'PERSONAL PROTECTION: Wear full protective clothing.

FIRE FIGHTING PHASES: Do not use water, carbon dioxide, dry'- chemical or halogenated extinguishing agents. Fires may.be smothered by applying a nietal cover. Dry graphite or ground. dolomite may also be used to smother fires in sodium hydride.

USUAL SHIPPING CONTAINERS: Polyethylene bags packed in metal containers. Metal cans or drums.

STORAGE: Protect against physical damage. Store in isolated, well-ventilated, cool, dry area. Use all precautions to keep water from entering storage area. Building must be well ventilated and so constructed as to eliminate pocketing of hydrogen gas. Do not remove oil from sodium hydride slurries.

REMARKS: Open containers only in inert atmospheres or low humidity rooms. If the use of sodium hydride can result ih hazardous concentrations of hydrogen, electrical installations should conform to the National Electrical Code requirements for Class I hazardous locations and electrical equipment should be suitable for Group B atmospheres. See National Electrical Code (NFPA No. 70).

SULFURYL CHLORIDE $02C12

DESCRIPTION: Colorless liquid with a pungent odor. Turns yellow on standing because of dissociation into sulfur dioxide and chlorine.

FIRE AND EXPLOSION HAZARDS: Nonflammable liquid. Reacts violently w'ith water or steam to produce heat, toxic and corrosive fumes. 473 REVISIONS TO NFPA NO. 49 49-23

LIFE HAZARD: Sulfuryl chloride is a highly toxic, highly irritating liquid. The vapors may cause acute respiratory irritation and delayed pulmonary edema. Also the vapors are corrosive to human skin and the mucous membranes. When heated to decomposition, it emits highly toxic fumes of chlorides and oxides of sulfur. PERSONAL PROTECTION: Wear full protective equipment. FIRE FIGHTING PHASES: Avoid water contact with sulfuryl chloride since there is the possibility of a violent reaction. Water may be used to keep fire-exposed containers cool. USUAL SHIPPING CONTAINERS: Glass stoppered carboys , steel or nickel drums and tank cars. STORAGE: Store in tightly stoppered containers in a cool dry location and away from areas of acute fire hazard.

TETRACHLOROETHYLENE CC12:CCI~ DESCRIPTION: Clear liquid with mild chloroform-like odor. FIRE AND EXPLOSION HAZARDS: NO flash point in conventional closed tester; nonflammable. Ignition temperature, none. Boil- ing point, 250 ° F (121 ° C). Liquid is heavier than water (specific gravity 1.6). Essentially insoluble in water. LIFE HAZARD: Incoordination and impaired judgment may occur at vapor exposures from 300 ppm to 1000 ppm. Dizziness, drowsiness, loss of consciousness and even death can occur at increasing levels of exposure. When involved in fire, tetrachloroethylene emits highly toxic and irritating fumes. PERSONAL PROTECTION: Wear self-contained breathing apparatus. FIRE FIGHTING PHASES: Use water spray to keep fire-exposed containers cool. Water spray may be used to flush spills away from exposures. USUAL SHIPPING CONTAINERS: 5- and 55-gallon steel drums; tauk cars, and tank trucks. STORAGE: Store in a cool, dry, well-ventilated location, away from any area where the fire hazard may be acute. REMARKS: See Chemical Safety Data Sheet SD-24 (Manufactur- ing Chemists' Association, Inc.). 474 49-24 COMMITTEE ON CHEMICALS AND EXPLOSIVES

THIONYL CHLORIDE SOC12 h/~ DESCRIPTION: Colorless fuming liquid With suffocating odor. FIRE AND EXPLOSION HAZARDS: Nonflammable liquid. M-~y react violently with water or moist air. LIFE HAZARD: Thionyl chloride is a fuming liquid whose vapors can cause strong corrosive irritation of skin, eyes and mucous membranes. The liquid can cause serious burns on contact with any of these tissues. Through the action of water it decomposes to sulfur dioxide, chlorine, sulfur monochloride and hydrogen chloride, all toxic chemicals. Decomposes when heated above 284 ° F (140 ° C) forming chlorine, sulfur dioxide and sulfur monochloride and giving a suffocating odor. PERSONAL PROTECTmN: Wear full protective clothing. FreE FIGHTING PHASES: Avoid water contact with thionyl chloride since there is the possibility of a violent reaction. Water may be used to keep fire-exposed containers cool. USUAL SHIPPING CONTAINERS: Carboys, nickel drums or nickel tank cars. STORAGE: Protect against physical damage and water.

1,1,1-TRICHLOROETHANE. CH~CC13 DESCRIPTION: Clear liquid with mild chloroform-like odor. FIRE AND EXPLOSION HAZARI)S: NO flash point in conventional closed tester at ordinary room temperatures, but moderately flammable at higher temperatures. Flammable limits, 8.0% and 10.5%. Ignition temperature, 998°F (537 ° C). Boiling point, 165°F (74 ° C). Liquid is heavier than water (specific gravity, 1.3). Not soluble ill water. LIFE HAZAm): Incoordination and impaired judgment may occur at vapor exposures from 500 ppm -- 1000 ppm. Dizzi- ness, drowsiness, loss of consciousness and even death can occur at increasing levels of exposure. When involved in fire, 1,1,1-trichloroethane emits highly toxic and irritating fumes. PERSONAL PROTECTION: Wear ~elf-contained breathing apparatus. 475 REVISIONS TO NFPA NO. 49 49-25

FIRE FIGHTING PHASES: Use water spray to keep fire-exposed containers cool. Water spray may be used to flush spills away from exposures. USUAL SHIPPING CONTAINERS: 5- and 55-gallon steel drums; tank cars, and tank trucks. STORAGE: Store in a cool, dry, well-ventilated location, away from any area where the fire hazard may be acute. REMARKS: See Chemical Safety Data Sheet SD-90 (Manu- facturing Chemists' Association, Inc.).

TRICHLOROETHYLENE CHCI:CCI2 DESCRIPTION: Clear liquid with mild chloroform-like odor. FIRE AND EXPLOSION HAZARDS: NO flash point in conventional closed tester at ordinary room temperatures, but moderately flammable at higher temperatures. Flammable limits, 8.0% and 10.5%. Ignition temperature, 770 ° F (410 ° C). Boiling point, 189 ° F (87 ° C). Liquid is heavier than water (specific gravity, 1.5). Not soluble in water. LIFE HAZARD: Incoordination and impaired judgment may occur at vapor exposures from 300 -- 1000 ppm. Dizziness, drowsiness, loss of consciousness and even death can occur at increasing levels of exposure. When involved in fire, trichloroethylene emits highly toxic and irritating fumes. PERSONAL PROTECTION: Wear self-contained breathing apparatus. FIRE FIGHTING PHASES: Use water spray to keep fire-exposed containers cool. Water spray may be used to flush spills away from exposures. USUAL SHIPPING CONTAINERS: 5- and 55-gallon steel drums; tank cars, and tank trucks. STORAGE: Store in a cool, dry, well-ventilated location, away from any area where the fire hazard may be acute. REMARKS: See Fire-Hazard Properties of Flammable Liquids, Gases and Volatile Solids (NFPA No. 325M)), Chemical Safety Data Sheet SD-14 (Manufacturing Chemists' As- sociation, Inc.). 476 49-26 COMMITTEE ON CHEMICALS AND EXPLOSIVES

TRICHLOROSILANE HSiCl~

DESCRIPTION: Colorless liquid below 89°F (32 ° C) with an acrid odor; fumes in air.

FIRE AND EXPLOSION HAZARDS: Fl,~mmable liquid. Vapor forms flammable mixtures in air. Flash point, 7 ° F (oc) (minus 14 ° C); flammable limits not reported; vapor is heavier than air (vapor density, 4.7). Reacts violently with w,~ter, yielding hydrochloric acid. (See Hydrogen Chloride.)

LIFE HAZARD: Vapor and liquid cause burns; toxic on inhalation. Reacts with water to form hydrochloric acid. (See Hydrogen Chloride.)

PERSONAL PROTECTION: Wear full protective clothing:

FIRE FIGHTING PHASES: Use dry chemical or carbon dioxide to extinguish small fires. Flooding with water may be necessary to prevent reignition. Water may be used if large amounts of combustible materials are involved and if fire fighters can protect themselves by distance or barriers from the violent trichlorosilane-water re.~etion. Water may be used to keep fire-exposed containers cool.

USUAL SHIPPING CONTAINERS: 55-gallon drums; lgallon glass bottles.

STORAGE: Protect against physical damage. Outside or detached storage is preferred. Inside storage should be in ~ standa.rd flammable liquids storage room or cabinet. Separate from oxidizing materials.

RE.~IARKS: Spills c~n be neutralized by flushing with large quantities of water followed by treatment with sodium bicarbonate. Provide adequate protection against genergted hydrogen chloride. Do not allow water to get into the container since resulting pressure could cause the container to rupture. Electrical installations in Class I hazardous locations, as defined in Article 500 of the National Electrical Code, should be in accordance with Article 50l of the Code, and electrical equipment should be suitable for use in atmospheres contai~ing trichlorosilane vapors. See National Electrical Code (NFPA No. 70), and Flammable and Com- bustible Liquids Code (NFPA No. 30). 477 REVISIONS TO NFPA NO. 49 49-27

TRIETHYLAMINE (C2Hs)3N

DESCRIPTION: Colorless liquid with an ammoniacal odor.

FIRE AND EXPLOSION HAZARDS: Flammable liquid. Vapor forms explosive mixtures with air. Flammable limits, 1.2% and 8.0%. Flash point, 20 ° F (oc) (minus 7 ° C). Vapor is heavier than air (vapor-air density at 68°F (20 ° C), 1.2)aild may travel a considerable distancc to a source of ignition and flash back. Soluble in water.

LIFE HAZARD: V~pors are a severe irritant to the eyes and nm- cous membranes. High concentrations can be toxic.

PERSONAL PROTECTION: Wear self-contained breathing apparatus.

FIRE FIGHTING PHASES: Use water spray, dry chemical, "alcohol" foam, or carbon dioxide. Use water to keep fire-exposed containers cool. Water spray may be ineffective as an extinguishing agent (see Explanatory). Direct hose streams from a protected location. If a leak or spill has not ignited, use water spray to disperse the vapors and to protect men attempting to stop a leak. Water spray m~y be used to flush spills ~way from exposures and to dilute spills to nonflammable mixtures.

USUAL SHIPPING CONTAINERS: Tank barges, drums, tank cars, t,mk trucks, and portable tanks. (Drums to 55-gallons and tanks to 20,000 pounds gross.)

STORAGE: Protect against physical damage. Separate from oxidizing materials. Outside or detached storage is preferred. Inside stor~tge should be in a standard flammable liquid storage room.

REMARKS: Electrical installations in Class I hazardous locations as defined in Article 500 of the National Electrical Code should be in accordance with Article 50l of the Code; and electrical equipment should bc suitable for use in atmospheres containing triethylamine vapors. 478 49-28 COMMITTEE ON CHEMICALS AND EXPLOSIVES

VANADIUM TETRACHLORIDE VCL

DESCRIPTION: Dark reddish to brown liquid, fumes in moist air.

FIRE AND EXPLOSION HAZARDS: Noncombustible, corrosive liquid; will react violently with water to form v~nadium trichloride, vanadium oxydichloride and hydrochloric acid. Specific gravity, 1.8.

LIFE HAZARD: Vapors ~re extremely toxic ~nd corrosive. Contact with skin, eyes, nose ~nd throat causes severe burns and irritations. Inhalation of high concentration, absorption through: skin, or ingestion may be fatal.

PERSONAL'PROTECTION: Wear full protective clothing.

FIRE FIGIJTING PHASES: Dry chemical and carbon dioxide are the preferred extinguishing agents for fires in the.vicinity of vanadium tetrachloride. The use of water must be avoided except to cool surrounding containers where there is no danger of water coming into contact with the vanadium tetrachloride. In the event of minor spills, flush with large quantities of water, then neutralize with sodium carbonate when fumes subside. For major spills, cover with foam or sod~ ash, then hydrolize the product in a controlled manner using a water fog.

USUAL SHIPPING CONTAINERS: Cylinders or steel portable tanks.

STORAGE: Protect against physical damage. Keep containers upright and tightly closed when not in use. All tanks, cylinders, other storage vessels and transfer piping should be chnrged with a blanket of nitrogen at not less than 5 psi. Separate from combustible or. reactive -m~terials. Store in ~ cool, dry, well- ventilated location, away from sunlight, heat, steam pipes or any area where the fire hazard may be acute. Outside or detached, well-isolated storage is preferred. Keep away from water or location where water may be needed for fire control in other storage or for fire involving the building. Chill to below 68 ° F (20 ° C) before opening. 479 REVISIONS TO NFPA NO. 49 49-29

28. Synonyms. Insert the foUowing synonyms in the body of the Slandard.

ARSENIOUS CHLORIDE See ARSENIC CHLORIDE

ARSENOUS CHLORIDE See ARSENIC CHLORIDE

BUTTER OF ARSENIC Sc(~ ARSENIC CHLORIDE

CAUSTIC ARSENIC CHLORIDE. See ARSENIC CHLORIDE

~CAUSTIC OIL OF ARSENIC S~ ARSENIC CHLORIDE

CHLOREX Sec DICHLOROETHYL ETHER

GAMMA CHLOROALLYL CHLORIDE Sce 1~ 3-1)ICHLOROPROPENE

CHLOROCHROMIC ANHYDRIDE Scc CHROMYL CHLORIDE

CHROMIUM OXYCHLORIDE Sce CHROMYL CHLORIDE

CUMOL See CUMENE

2,2'-DICHLOROD1ETHYL ETHER SCC DICHLOROETHYL ETHER

1, 3-DICHLOROPROPYLENE See l, 3-DICHLOROPI$OPENE

FUMING LIQUID ARsENIc See ARSENIC CHLORIDE

HYDROGEN IODIDE Sec HYDRIODIC ACID

ISOPROPYLBENZENE Sec CUMENE

METHOXYMETHANE See DIMETHYL ETHER

2-METHYLBUTANAL See 2-M ETHYLBUTYRALDE- / HYDE

METHYL CHLOROFORM See l, 1, 1-TRI- CHLOROETHANE 480 49-30 COMMITTEE ON CHEMICALS AND EXPLOSIVES

METHYL ETHER See DIMETHYL ETHER

METHYL OXIDE S~e DIMETHYL ETHER

PERCHLOROETHYLENE S(~e TETRACH LOROETHY LEN E

SILICOCHLOROFORM S(~e TR1CHLOROSILA NE

SODIUM DICHLOROISOCYANURATE DIHIDRATE See SODIUM DICHLORO-S- TRIAZINE TRIONE- DIHYDRATE SULFURIC OXYCHLOR1DE S(~e SULFURYL CHLORIDE

SULFUROUS OXYCHLORIDE S(~e THIONYL CHLOI~.IDE

TEL COMPOUND S(~e MOTOR FUEL ANTI- KNOCK COMPOUNDS (C011- t~ining lead) TEN See TR1ETHYLAMINE TETRAETHYL LEAD (TEL COMPOUND) See MOTOR FUEL ANTI- KNOCK COMPOUNDS (containing lead) TETRAMETHYL LEAD (TML COMPOUND) See ~IOTOR FUEL ANTI -~ KNOCK COMPOUNDS (coil- raining lead) TML COMPOUND See .~IOTOR FUEL ANTI- KNOCK COMPOUNDS (coil- raining lead) TRICHLOROMONOSILANE See TRICHLOROSILANE 481 497-5

Part ii

Proposed Recommended Practice for Classification of

Class I Hazardous Locations for Electrical Installations

NFPA No. 497.1975

Chapter 1 Introduction

1-1 Purpose.

1-1.1 Electrical installations in locations hazardous because of flammable atmospheres can be suitably designed if the zones of potential hazard are clearly defined. It is the intent of this Recommended Practice to present a basis for the classification of such locations for electrical installations in chemical plants. As used here, a chemical plant is a large integrated plant or the portion of such a plant where flammable or combustible liquids are produced by chemical reactions or used in chemical reactions. NOTE: Throughout this Recommended Practice reference is made to areas, spaces, locations, and zones. In general, the word "areas" has been used to designate a two-dimensional space. Spaces, locations, and zones should be considered interchangeable terms designating a three- dimensional space.

1-1.2 If a location is to be classified correctly,-certain questions need to be answered: Does a hazardous location exist? If it does, what type is it and how far does it extend? The puv:,ose of this Recommended Practice is to provide assistance in answering those questions. 1-1.3 This Recommended Practice uses the criteria estab- lished by the National Electrical Code, NFPA No. 70-1975, for classifying hazardous locations. Once a location has been 482 497-6 CLASS 1 HAZ. LOCATIONS---ELECT. INSTALLATIONS classified there should be little difficulty in making a proper electrical installation because the National Electrical Code specifies the type of equipment and wiring methods to be used.

1-2 Scope.

1-2.1 This Recommended Practice applies to those locations where flammable gases and volatile flammable liquids are processed, stored, loaded, unloaded or otherwise handled. 1-2.2 Chemical and physical changes may occur during the handling and use of flammable liquids, gases and vapors. The composition and properties of materials may change dras- tically during processing or under abnormal conditions. Those properties and chemical changes were considered in the preparation of this Recommended Practice. 1-2.3 This Recommended Practice is not an attempt to rewrite or otherwise supersede the National Electrical Code. 1-2.4 This Recommended Practice is a guide to safe practices and should be applied with sound engineering judgment. When all factors are properly evaluated, a consistent classification can be developed. 483 GENERAL INFORMATION 497-7

Chapter 2 General Information

2-1 National Electrical Code Criteria and Equipment Con- siderations.

2-1.1 Article 500 of the National Electrical Code defines Class I locations as those in which flammable gases or vapors are or may be present in the air in quantities sufficient to produce explosive or ignitible mixtures; Class II locations are those which are hazardous because of the presence of combustible dust; and Class III locations are those which are hazardous because of the presence of easily ignitible fibers or flyings, but in which such fibers or flyings are not likely to be in suspension in air in quantities sufficient to produce ignitible mixtures. NOTE: These classes are unrelated to the National Fire Protection As- sociation (NFPA) definitions covering flammable liquids as discussed in 2-3.3.

2-1.2 Within each location class, the National Electrical Code recognizes two divisions. Within Class I these divisions are" 2-1.2.1 Division 1. The criterion for these locations is that they are likely to have flammable mixtures present under normal conditions. (a) Installations for Division 1 locations are designed so that operation or failure of any portion of the electrical system will not release flame or hot,gases or have high enough surface temperatures to ignite the surrounding atmosphere.

2-1.2.2 Division 2. The criterion for these locations is that they are likely to have flammable mixtures present only under abnormal conditions, such as the failure or rupture of equipment. (a) Installations for Division 2 locations use equipment arranged so that full operation of the electrical system (including arcing and similar devices) may occur without providing a source of ignition under normal conditions. Complete protection is 484 497-8 CLASS I HAZ. LOCATIONS--ELECT. INSTALLATIONS not provided against ignition due to electrical breakdown inasmuch as electrical breakdowns occur very rarely and equipment is usually de- energized automatically. 2-1.2.3 By inference, locations which cannot be classified as Division 1 or 2 are nonhazardous under the Na- tional Electrical Code. 2-1.$ Unfortunately, no single type of electrical equipment enclosure is best in all respects. Electrical installations must be designed to protect against power failures, accidental grounds, and electric shock resulting from personal contact with energized conductors, in addition to avoiding the proba- bility of accidental ignition of flammable liquids, vapors, or gases released to the atmosphere. Explosionproof equipment---correctly designed, manufactured, installed, and maintainedmprovides the best protection against ignition when flammable mixtures are present. However, general-purpose equipment located outside the hazardous location provides the relaying and automatic controls which best insure against ignition due to electrical faults. Equipment with general purpose enclosures has features that permit easier maintenance with proper worker protection and with minimum power service interruption. The safest electrical systems would use to advan- tage the best features of each type. 2-1.4 Factors such as corrosion, weather, maintenance, equipment standardization and interchangeability, and possible process changes or expansion frequently dictate the use of special enclosures or installations for electrical systems. How- ever, such factors are outside the scope of this publication, which is concerned entirely with the proper application of electrical equipment to avoid ignition of flammable mixtures. 2-1.5 Aside from considerations relative to enclosure in- tegrity, other approaches can be taken in electrical design that may be equally effective. 2-1.5.1 It is also possible to locate electrical equipment, such as switchgear, transformers and starters, outside of the hazardous locations. 2-1.5.2 Positive pressure (above atmospheric) of an enclosure or rooms from a source of clean air is permissible by the National Electrical Code (Section 500-1) if adequate 485 GENERAL INFORMATION 497-9 safeguards are incorporated in the installation. Part A of the Standard for Purged and Pressurized Enclosures for Electrical Equipment in Hazardous Locations, NFPA No. 496-1974, contains requirements for pressurized enclosures and rooms. 2-1.5.$ An approach that is effective, where power levels are low is to use intrinsically safe electrical systems, which are also recognized by the National Electrical Code. Require- ments for intrinsically safe installations are contained in the Standard for Intrinsically Safe Process Control Equipment for Use in Class I Hazardous Locations, NFPA No. 493-1969.

2-2 Conditions Necessary for a Fire or Explosion.

2-2.1 Three basic conditions .must be satisfied for the occurrence of a fire or explosion. These are: 1. A flammable gas or vapor must be present. 2. It must be mixed with air in the proportions required to produce a flammable or ignitible mixture. Further, within the context of this publication, there must be a sufficient amount of this mixture to provide an ignitible atmosphere surrounding the electrical installation. 3. There must be an ignition of this mixture. Within the context of this publication, the source of ignition is understood to be the electrical installation operating at energy levels sufficient to release incendiary energy. 2-2.2 In classifying a particular location, the first basic condition, presence of a flammable gas or vapor, is a.significant factor in determining the division classification. The decision is based principally on whether the flammable mixture may be present: a, under normal operating conditions; or, b, only under abnormal operating conditions or equipment breakdown. 2-2.3 The second basic condition is important in determining the limit or extent, of the hazardous location. The quantity of the substance that might be liberated, its physical characteristics, and the natural tendency of gases and vapors to disperse in the atmosphere must be recognized. Conditions 1 and 2 will be considered (see 2-4, 2-5, and 2-6) following a discussion of volatility and' flammability characteristics of. the gases and liquids. 486 497-10' CLASS 1 HAZ. LOCATIONS---EI.EC'I'. INSTAI,LATIONS

2-3 Flammable Liquids, Gases and Vapors. 2-3.1 Lighter-than-air Gases. 2-3.1.1 Lighter-than-air gases released from an opening will often dissipate rapidly because of their low relative density and will not usually affect as wide an area as the vapors of flammable liquids or heavier-than-air gases. Except in enclosed spaces, these lighter-than-air gases seldom produce hazardous mixtures in the zones close to grade where most electrical ,installations are made. 2-3.2 Compressed Liquefied Flammable Gases. 2-3.2.1 Vapor pressures of these gases exceed 40 psia at 100°F (37.8°C). Compressed flammable gases released as liquids are highly volatile and have low boiling temperatures so that they readily pick up heat and vaporize, creating large volumes of cold gas. Especially when released at or near ground level, gases normally heavier than air and also those heavier only because they are cold will travel along the ground for long distances if air currents do not assist diffusion. When the gases are released at some distance above ground level, or upward at substantial velocity, diffusion is faster and the spread from point of release is usually much less. 2-3.3 Flammable and Combustible Liquids. 2-3.3.1 Flammable liquids vary in volatility and are defined in the Standard on Basic Classification of Flammable and Combustible Liquids, NFPA No. 321-1973, as being any liquid having a closed cup flash point below 100°F (37.80C) and a vapor pressure not exceeding 40 pounds per square inch absolute (2068.5 mm) at 100°F (37.8°C). Combustible liquids are defined as those having a closed cup flash point at or above 100°F (37.8°C). 2-3.3.2 NFPA No. 32!-1973 subdivides flammable and combustible liquids as follows: Class I: Those having flash points below 100°F (37.8°C), Class II: Those having flash points at or above 100°F (37.80C) and below 1400F (60°C). Class III: Those having flash points at or above 140°F (60°C). NOTE: Classes I, II and Ill as used here to identify flammable and combustible liquids should not be confused with the same terms in the National Electrical Code (see 2-1.1). 487 GENERAl. INFORMATION 497-11

2-3.3.3 Densities of air saturated with vapors of flammable liquids at ordinary atmospheric temperatures are generally less than 1.5 times that of air. However, when these vapors are diluted with sufficient air to make a flammable mixture, the density of the mixture approaches that of air. 2-3.3.4 Class I liquids, where released in appreciable quantities to the open, may produce large volumes of vapor. This is particularly the case with the more volatile liquids in this class, such as natural, motor, and aviation gasolines. The heavier liquids in this class, such as some of the thinners and solvents, xylenes, and some intermediate refinery stocks, release vapor more slowly at normal storage temperatures and are hazardous only near the surface of the liquid. At elevated temperatures, however, these heavier liquids give off larger volumes of vapor that can spread farther. These vapors, even when evolved rapidly, have a natural tendency to disperse into the atmosphere and, thus, rapidly become diluted to concentrations below the lower limit of the ignitible range. This tendency is greatly accelerated by air movement. Experience has confirmed that outdoor locations requiring classification" are only a small fraction of those that might theoretically be hazardous, based on a given rate of release of a flammable gas or liquid. 2-3.3.5 Class II liquids include kerosine, many solvents, some heating oils, and diesel fuel. The degree of hazard is low because the rate of vapor release is almost nil at normal temperatures of handling and storage. When these liquids are heated, more vapor is released and the hazard may be increased near the point of release. But, the chances of ignition by electrical equipment is not as great as for Class I liquids because the vapors will not travel as far since they tend to condense as they are cooled by the surrounding air. If heated to extremely high temperatures, the vapors may ignite spontaneously.when released to the atmosphere; electrical ignition sources are not involved in this case.

2-3.3.6 Normally, Class I liquids will produce vapors considered to be in the flammable range for electrical design purposes. Class II liquids should be considered as producing flammable vapors in the atmosphere near the point of release when handled, processed, 'or stored under conditions that may cause the temperature of the liquid to exceed its flash point. 488 497-12 CLASS I HAZ. LOCA'I;IONS---ELECT. INSTALLATIONS 2-3.3.7 Liquids having flash points at or above 140°F (600C) are designated Class III. Such liquids may release vapor at their surface if heated above the flash point, but the extent of the hazardous zone will ordinarily be very small. These combustible liquids of low vapor pressure seldom evolve sufficient quantities of vapor to render any significant zone hazardous.

2-4 Division I Hazardous Locations.

2-4.1 The decision to classify a location as hazardous is based upon the possibility that a fammable mixture may be present. Having decided that a location should be classified hazardous, the next step is to determine the degree of hazard: Is the location Division 1~ or Division 2? 2-4.2 As stated in 2-1.2.1, the criterion for Division 1 is whether the location is likely to have flammable mixtures present under normal .conditions. For instance, the presence of flammable vapors in the vicinity of open-dome loading of gasoline tank trucks is "normal" and requires a Division 1 classification. However, normal does not necessarily mean the situation which prevails when everything is working properly. For instance, a process procedure might be so sensitive to control that relief valves frequently open. This can be considered normal. If these valves release flammable liquid or vapor to the atmosphere, the zone adjacent to the point of release is classified as Division 1. However, if the operation of the relief valves occurs infrequently under unusual conditions, it is not to be considered normal. 2-4.3 Similarly, there may be cases in which frequent maintenance and repair are necessary. These are viewed as normal and, if quantities of flammable liquid, gas or vapor are released as a result of the maintenance, the location is Division 1. However, if repairs are not usually required between turn- arounds, the need to do repair work is considered abnormal. In any event, the classification of the location, as related to equipment maintenance work, is influenced by the maintenance procedures and frequencies.

2-5 Division 2 Hazardous Locations.

2,5.1 The criterion for Division 2 locations is whether the location :is1~likely:,to ~have J flammable :~mixvur.es~. preSe~nV ~only 489 GENERALINFORMATION 497-13 under abnormal conditions. The term "abnormal" is used here in a limited sense and does not include a major catastrophe. 2-5.2 As an example, consider a vessel containing hydrocarbons to be a source which releases flammable material only under abnormal conditions. In this case, there is no Division 1 location because the vessel is normally tight. To release vapor, the vessel would have to leak, and that would not be normal. Thus, the vessel is surrounded by a Division 2 zone. Everything outside that zone is classified nonhazardous. 2-5.3 Process equipment does not fail very often. Fur- thermore, the National Electrical Code requirements for electrical installations in D~visi6n 2 locations are such that an ignition-capable spark can occur in a flammable vapor-air mixture only in an explosionproof enclosure, or in the event of a breakdown of electrical equipment. On a realistic basis, the possibility of simultaneous abnormal conditions is very remote; this consideration justifies the recognition and acceptance of the Division 2 concept (erroneously called semihazardous areas). 2-5.4 The Division 2 classification is equally applicable to a condition not involving equipment failure. Consider for example the situation wherein a Division 1 location exists because of the normal presence of flammable mixtures. Here, Division 2 is the classification applied to the zone which normally exists between a Division 1 location and a nonhazardous location. Obviously one side of an imaginary line cannot be normally hazardous and the opposite side never hazardous. Consider the case of a source which releases flammable material during normal operation. This source is surrounded by a Division 1 location which, in turn, is surrounded by a larger concentric Division 2 location. Division 2 is the transition zone, and the area outside the Division 2 location is classified nonhazardous. 2-5.5 There could, of course, be cases in which an unpierced barrier, such as a blank wall, might serve completely to prevent vapor spread. In such a case, this concept would not apply and there would be no Division 2 location.

2-6 Nonhazardous Locations.

2-6.1 Experience has shown that the occurrence of flammable, material.!iberation , from, some, .operations and ap. 490 497-14 CLASS I HAZ. LOCATIONS--ELECT. INSTALLATIONS paratus is so infrequent that it is not necessary to classify the surrounding locations hazardous. For example, it has not been found generally necessary to classify as hazardous the following locations where flammable gases and liquids are processed, stored, or handled: . Locations that are adequately ventilated where flammable substances are contained in suitable, well- maintained, closed piping systems which include only the pipe, valves, fittings, flanges, and meters.

. Locations that are not adequately ventilated, and where the piping systems for flammable substances are without valves, fittings, flanges, and similar accessories.

. Locations where the flammable liquids or gases are stored in suitable containers. Regulations of the U. S. Department of Transportation specify containers that may be used to ship flammable liquids and gases (Title 49, Chapter I, Parts 170-189, Code of Federal Regulations). Container requirements for storing flammable and combustible liquids will be found in the Flammable and Combustible Liquids Code, NFPA No. 30-1973, Chapter IV.

2-6.2 An adequately ventilated location is any building, room, or space which is substantially open and free from obstruction to the natural passage of air through it, vertically or horizontally. Such locations may be roofed over with no walls or may be closed on one side. 2-6.3 An enclosed or partly enclosed space may be considered as adequately ventilated if it is provided with artificial ventilation in an amount equivalent to natural ventilation under low-wind-velocity conditions and there are adequate safeguards against the failure of the ventilation equipment. Adequate ventilation is defined in NFPA No. 30 as that which is sufficient to prevent accumulations of significant quantities of vapor-air mixtures in concentrations over one-fourth of the lower flammable limit. (For a ten-foot-high room, a flow of at least one cubic foot per minute per square foot of floor area or at least six changes per hour is adequate. For higher rooms or unusual configurations, these figures may have to be modified.) 491 GENERALINFORMATION 497-15

2-6.4 Improper exhaust provisions constitute inadequate ventilation. For example, if the vapors to be removed are heavier than air, exhaust openings should be near the floor. 2-6.5 In locations containing thermal ignition sources (such as open flames), electrical installation design will not eliminate ignition sources. Thus, these locations are classified electrically as nonhazardous. Fire and explosion prevention depends upon the avoidance of flammable mixtures.

2-7 Extent of Hazardous Locations.

2-7.1 The extent of a Division 1 or Division 2 zone requires careful consideration. Perhaps a good beginning is to start with the fact that hydrocarbons are generally heavier than air. This leads to the following conclusions: 1. In the absence of walls, enclosures, or other barriers, and in the absence of air currents or similar disturbing forces, it must be assumed that a vapor will disperse in all directions, as governed by the vapor density and velocity (e.g., heavier-than-air vapors principally downward and outward, lighter-than-air vapors principally upward and outward). Thus, if the source of hazard were a single point, the horizontal area covered by the vapor would be a circle. 2. For heavier-than-air vapors released at or near grade level, the locations where potentially hazardous concentrations are most likely to be found are below grade; those at grade are next most likely; and, as the height above grade increases, the potential hazard decreases. In open locations away from the immediate point of release, freely drifting vapors from a source near grade seldom have reached ignition sources at elevations more than six feet or eight feet above grade. For lighter-than-air gases the opposite is true; there is little or no potential hazard at and below grade, and greater potential hazard above grade. 3. Elevated or depressed sources of vapor release, or release of flammable vapor under pressure, may substantially alter the outline of the limits of the hazardous location. Also, a very mild breeze may extend these 492 497-16 CLASS 1 HAZ. L'~t~CATIONS--ELECT. INSTALLATIONS

limits in the direction of air movement. However, a stronger breeze can so accelerate the dispersion of vapors that the extent of the hazardous location would be greatly reduced. Thus, dimensional limits recommended for Division 1 or Division 2 locations must be recognized from experience, rather than being based on any theoretical diffusion of vapors of the type concerned. 2-7.2 The degree to which breeze and volatility combine to affect the extent of the hazardous location can be illustrated by two experiences, checked by combustible gas detectors. Motor gasoline spilled in a sizable open manifold pit gave no indication of flammable mixtures beyond three feet or four feet from the pit when the breeze was 8 mph to 10 mph. A slightly smaller area of a more volatile liquid from a pool blocked on one side was checked during a gentle breeze. At grade, vapors could be detected for approximately 100 feet downwind; however, at 18 inches above grade, there was no indication of vapor as close as 30 feet from the pool. 2-7,2.1 Such examples show thateven heavy vapor is rapidly dispersed in an adequately ventilated location; for this reason, outdoor locations or locations having ventilation equivalent to normal outdoor conditions are generally classified as Division 2. However, wherever ventilation is inadequate, flammable mixtures can develop and the situation may justify a much larger zone being classified as Division 1. 2-7.3 The size and type of construction of a building may have considerable influence on the hazard classification of the enclosed volume. 2-7.3.1 In the case of small sampling or testing rooms, well-constructed but with inadequate ventilation, it might be appropriate to classify the entire internal volume as Division 1. 2-7.3.2 On the other hand, some large buildings used for such diverse operations as warehousing, processing, can- ning, and shipping often have substantial artificial ventilation prov!ded, or the building has many doors and windows which are m intermittent use or are continuously open. Building construction design may permit a substantial degree of natural ventilation which, coupled with such factors as volumetric con- tent of the building, floor area, lineal dimensions of walls and 493 : GENERAL INFORMATION 497-17

ceiling height, would readily justify consideration of that building as an adequately ventilated indoor location. Here, certain ~pordons of the enclosed location may be classified as Division 1 (surrounded by a larger Division 2 location), or Division 2, with the remainder of the building enclosure designated as nonhazardous. 2-7.4 When classifying buildings there should be careful" evaluation of prior experience with the same or related types of installations. It is not enough to merely point to a potential source of vapor within the building and proceed immediately witff the definition of the extent of the Division 1 and Division 2 locations. Where experience has indicated that a particular design, concept is sound, a more hazardous classification for similar installations is not justified. Furthermore, it is conceiv- able that a location might be reclassified from Division 1 to Division 2, or from Division 2 to nonhazardous, based on experience. 2-7.5 Correctly evaluated, an installation will be found to be a multiplicity of Division 1 locations of extremely limited extent. Probably the most numerous of offenders are packing glands. A gland leaking a quart a minute (360 gallons per day) certainly could.not be commonplace; yet, if a quart bottle were emptied every minute outdoors, the zone made hazardous would be 'hard to locate with a combustible gas detector. Leak- ~age from a heavily frosted petroleum light-ends pump gland is difficult to pick up with a detector even three feet away in an adequately ventilated location. 2-7.6 Volume of liquid or vapor released is of extreme importance in determining the extent of a hazardous location, and it is this consideration which necessitates the greatest application of sound engineering judgment. However, one cannot lose sight of the purpose of this judgment, i.e., the location is classified solely for the installation of electrical equipment. 494 497-18 CLASS I I-tAZ. LOCATIONS--ELECT. INSTALLATIONS

Chapter 3 Method of Determining Degree and Extent of Hazardous Locations

3-1 Basis for Recommendations.

3-1.1 Some of the following recommendations for determining the degree and extent of hazardous locations have been developed by survey and. analysis of the practices of a large segment of the petroleum refining industry, by use of available experimental data, and by careful weighing of perti- nent factors. These recommended limits of hazardous locations for refinery installations may be more restrictive than are warranted for other types of facilities handling hydrocarbons. Other of the recommendations are based on NFPA documents that represent many hundreds of man-years of experience. The difference between the experience of the petroleum refining industry and other sources are basically related to quantities of material in process, use and storage. 3-1.2 Throughout this chapter references are made to small (low), moderate and large (high) pressures, tanks and buildings. Table 3-1.2 defines those terms as used in this chapter.

Table 3-1.2 Relative Magnitude* Small (Low) Moderate Large (High) Pressure Range Less than 100 psi 100 psi to less 500 psi or greater than 500 psi Tank Size Less than 5,000 5,000gallons 25,000 gallons gallons to less than or greater 25,000 gallons Building Volume Less than 2,500 2,500cubic feet 6,000cubic feet cubic feet to less than or greater 6,000 cubic feet * Experience with similar installations may justify deviation from the definition in tbe Table. See 2-7.4.

3-2 Vapors Assumed to be Heavier than Air.

3-2.1 In setting limits; it is generally assumed that flammable vapors are heavier than air. Classification on this 495 DEGREE AND EXTENT OF HAZARDOUS LOCATIONS 497-19 basis is normally conservative for lighter-than-air gases or vapors. However, some modification of the limits may be necessary to accommodate certain lighter-than-air situations.

3-3 Procedures for Classifying Locations.

3-3.1 The following procedure requires answers to a series of questions. Each room, section, or zone should be considered individually in determining its classification. 3-3.2 Step 1--Need for Classification. The need for classification is indicated by an affirmative answer to one of the following questions: (a) Are flammable liquids, vapors or gases likely to be present? (b) Are liquids having flash points at or above 100°F (37.8°C) likely to b-e handled, processed, or stored at temperatures above their flash points? 3-3.3 Step 2--Assignment of Classification. Assuming an affirmative answer results from Step 1, the following questions should be used to determine the assignment of classification. 3-3.3.1 Division 1 locations may be distinguished by an affirmative answer to any one of the following questions: (a) Is a flammable mixture likely to exist under normal operating conditions? (b) Is a flammable mixture likely to occur frequently because of maintenance, repairs, or leakage? (c) Would a failure of process, storage, or other equipment be likely to cause an electrical failure simultaneously with the release of flammable gas or liquid? (d) Is the flammable liquid or vapor piping system in an inadequately ventilated location, and does the piping system contain valves, meters, Or screwed or flanged fittings that are likely to leak? (e) Is the zone below the surrounding elevation or grade such that flammable liquids or vapors may accumulate therein? 496 497-20 CI.ASS I HAZ. LOCATIONS---EI.EUT, INS'I'ALLATIONS

3-3.3.2 Division 2 locations may be distinguished by an affimative answer to any one of the following questions: (a) Is the flammable liquid or vapor piping system in an inadequately ventilated location, and is the piping system (containing valves, meters, or screwed or flanged fittings) not likely to leak? (b) Is the flammable liquid or vapor being handled in an adequately ventilated location, and can liquid or vapor escape only during abnormal conditions, such as failure of a gasket or packing? (c) Is the location adjacent to a Division 1 location, or can vapor be conducted to the location as through •trenches, pipe, or ducts? (d) If positive mechanical ventilation is used, could failure or abnormal operation of ventilating equipment permit mixtures to build up to flammable concentrations? 3-3.3.3 Step 3mExtent of Hazardous Locations. The extent of a hazardous location may be determined by applying with sound engineering judgment the distances recommended in the diagrams in Figures 3-5.1(a) through 3-5.11(c).

3-4 Use of Diagrams.

3-4.1 The diagrams in this chapter show hazardous zones surrounding typical sources of flammable liquids, vapors and gases. Some of the illustrations apply to a single source; others apply to an enclosed space or to an operating unit. The intended use of these diagrams is to develop classification maps of operating units, buildings, departments, or plant locations. Elevations or sections will be required where different classifications apply at different levels. 3-4.2 An operating department will have many interact- ing sources of flammable liquid,-vapor or gas, including pumps, compressors, exchangers, vessel flanges, sampling stations, meters, operating and control valves. Accordingly, it requires judgment to set the boundaries of zones for electrical classification. 3-4.3 Use the Index to Diagrams, in 3-5, to select the diagram or diagrams which apply to each source or condition. 497

DEGREE AND EXTENT OF HAZARDOUS LOCATIONS 497-21

Determine the applicable Divisions, their extent, and their layout in light of the local environmental conditions. It is recommended that a layout be made of each hazardous zone based on the interaction .of individual sources described in 3-4.2.

3-4.4 It may be found that individual classification of a great number of sources in a location is neither feasible nor economical. Classification of an entire building or location as a single zone should be considered only after evaluation of the extent and interaction of various sources and zones within the location, or adjacent to it.

3-5 Index to Diagrams.

3-5.1 Figures 3-5.1(a) through 3-5.1(c) show hazardous zones around pumps and similar devices handling flammable liquids at low flow rates. Figure 3-5.1(a) Outdoors at grade. Figure 3-5.1(b) Indoors at grade with adequate ventilation or in a building witha pierced or open wall. Figure 3-5.1(c) Indoors above grade in building with adequate ventilation or with pierced or open wall.

3-5.2 Figures 3-5.2(a) through 3-5.2(d) show hazardous zones around pumps and similar devices handling flammable liquids at moderate flow rates. Figure 3-5.2(a) Outdoors at grade. Figure 3-5.2(b) Indoors with adequate ventilation. Figure 3-5.2(c) Indoors with adequate ventilation and with a pierced wall or full wall opening. Figure 3-5.2(d) Indoors with inadequate ventilation and with a pierced wall or full wall opening in a small or moderate-sized building.

3-5.3 Figures 3-5.3(a) through 3-5.3(g) show hazardous zones around pumps and similar devices handling flammable liquids at high flow rates or handling compressed liquefied flammable gases. Figure 3-5.3(a) Outdoors at grade. Figure 3-5.3(b) Outdoors above grade. Figure 3-5.3(c) In an equipment shelter with inadequate ventilation. Figure 3-5.3(d) Inadequate ventilation and nonvaportight roof and walls in building handling conipres~ed liquefied flammable gases. 498 497-22 CLASS 1 HAZ. LOCATIONS--ELECT,INSTALLATIONS

Figure 3-5.3(e) Inadequate ventilation and nonvaportight roof and walls in building handling flammable liquids. Figure 3-5.3(f) Indoors with adequate ventilation. Figure 3-5.3(g) Indoors with inadequate ventilation and with pierced or open building wfill.

3-5,4 Figures 3-5.4(a) through 3-5.4(h) show hazardous zones around process vessels and dryers handling flammable liquids at high, moderate and low flow rates. Figure 3-5.4(a) Outdoor process plant, high flow rate. Figure 3-5.4(b) Outdoor process plant, moderate flow rate. Figure 3-5.4(c) Indoor process area with adequate ventilation. Source at or near grade. Figure 3-5.4(d) Indoor process area with adequate ventilation. Source above grade. Figure 3-5.4(e) Indoorprocess area, high flow rates, inadequate ventilation. Source above .grade. Figure 3-5.4(f) Outdoor kettle installation. Figure 3-5.4(g) Indoor kettle installation, adequate ventilation. Figure 3-5.4(h) Product dryer in totally enclosed system, adequate ventilation.

3-5.5 Figures 3-5.5(a) and 3-5.5(b) show hazardous zones around storage tanks. Figure 3-5.5(a) Outdoors at grade. Figure 3-5.5(b) Open tanks or tanks with hatches normally open.

3-5.6 Figures 3-5.6(a) through 3-5.6(e) show hazardous zones during tank car and tank truck loading and unloading. Figure 3-5.6(a) Through closed dome with vapor recovery. Figure 3-5.6(b) Through bottom with vapor recovery. Figure 3-5.6(c) Through open dome, or through closed dome with atmospheric vent. Figure 3-5.6(d) Through bottom with atmospheric vent. Figure 3-5.6(e) Compressed flammable gases such :as liquefied petroleum gas.

3-5.7 Figures 3-5.7(a) and 3-5.7(b) show hazardous zones during drum and container loading and unloading and at drum storage areas. Figure 3-5.7(a) Loading, unloading outdoors and indoors with adequate ventilation. Figure 3-5.7(b) Storage indoors, opening between storage room and classified area. 499 DEGREE AND EXTENT OF HAZARDOUSLOCATIONS 497-23

3-5.8 Figure 3-5.8(a) shows hazardous zones around drainage ditches, separators, and impounding basins outdoors and in which flammable liquids are likely to be present. 3-5.9 Figure 3-5.9(a) shows hazardous zones around a dip tank that is indoors in an adequately ventilated location. 3-5.10 Figure 3-5.10(a) and 3-5.10(b) show hazardous zones in special situations where flammable liquids are being handled. Figure 3-5.10(a)Paint spray booth. Figure 3-5.10(b) Disp.ensirig stations, open centrifuges and other eqmpment where Class I flammable liquids are exposed.

3-5.11 Figures 3-5.11(a) through 3-5.11(c) show hazardous zones in special situations where lighter-than-air gases are' being handled. Figure 3-5.11(a) Liquid hydrogen, Figure 3-5.11(b) Gaseous hydrogen. Figure 3-5.11(c) Gas compressor in an inadequately ventilated shelter.

SOURCE

DIVISION 2 Figure 3-5.1(a). Pumps and similar devices handling flammable liquids at low flow rates and pressures, outdoors at grade. 500 497-24 CLASS I HAZ. LOCATIONS--ELECT. INSTALLATIONS

SOURCE

DIVISION 2 Figure 3-5.1(b). Pumps and similar devices handling flammable liquids at low flow rates, indoors with adequate ventilation or in a building with a pierced or open wall (not shown).

SOURCE~ OPENWALL

1•7"X•DIVISION 2 Figure 3-5.1(c). Pumps and similar devices handling flammable liquids at low flow rates, indoors above grade in a building with adequate ventilation or a pierced or open wall. 501 DEGREE souRiAND EXTENT OF HAZARDOUS LOCATIONS 497-25

,8 ,8

XV~\\1, 10' '] " 10' • \T~ II GRADE DIVISION 2

• Figure 3-5.2(a). Pumps and similar devices handling flammable liquids at moderate flow rates, outdoors at grade. (See NFPA No. 30-1973, Tables VI°9 and VII-I.)

~'~\ ~'~'R I1" ~'R-~~t DIVISION 1 ~ DIVISION 2 BELOW GRADE LOCATION SUCH AS SUMP OR TRENCH Figure 3-5.2(b). Pumps and similar devices handling flammable liquids at moderate flow rates, indoors with adequate ventilation. (See NFPA No. 30-1973, Tables 5650 and VII.I.) 502 497-26 CLASS 1 HAZ. [.OCATIONS---EI,ECT. INSTALLATIONS

P'~OEZAO" ONP,ERCED

,!" IIi 1 \'~'"110' MAXl GRA~E I~U'S'D~wA'L I" ='"~--'1 '~ .,v,. i ~ 25' MAX ~--- BE LOW GRADE LOCATION ~:~J DIVISION 1 ~'/'~DIVlSION 2 SUCH AS SUMP OR TRENCH Figure 3-5.2(c). Pumps and similar devices handling flammable liquids at moderate flow rates, indoors with adequate ventilation and with a pierced wall or full wall opening. (See NFPA No. 70-1975, Section 515-2(a) (1).)

PIERCED\ ~ ~RCED

GRADE BUILDING AS SUMP EITHER ~ DIVISION 1 [7"/~DIVISION 2 IN DIVISION 1 OR DIVISION 2 PORTION OF BUILDING Figure 3-5.2(d). Pumps and similar devices handling flammable liquids at moderate flow rates, indoors in a small or moderate-sized building with inadequate ventilation and with a pierced wall or full wall opening. (See NFPA No. 70-1975, Section 515-2(a) (2).) 503 DEGREE AND EX'I'I-NTOF HAZARI)OUSLOCATIONS 497-27

GRADE ~'~ DIVISION2 Figure 3-5.3(a). Pumps and similar devices handling flammable liquids at high flow rates or handling compressed liquefied flammable gases,* outdoors at grade. (*See NFPA No. 58-1974, Table 3-6.)

~ DIVISION 2 Figure 3-5.3(b). Pumps and similar devices handling flammable liquids at high flow rates or handling compressed liquefied flammable gases,* outdoors above grade. (*See NFPA No. 58-1974, Table 3-6.) 504 497-28 CLASS 1 HAZ. LOCATIONS--ELECT.INSTALLATIONS

AUXILIARY EO.UIPMENT ENCLOSURE

/I//Z~\\'q I I I I INADEOUATELY VENTILATED AREA I~ DIVISION 1 Figure 3-5.3(c). Pumps and similar devices handling flammable liquids at high flow rates or compressed liquefied flammable gases,* in an equipment shelter with inadequate ventilation. (*See NFPA No. 58-1974, Table 3-6.)

~//////~ ~ ~/////A / VAPLOLsRTIGHT

NON-VAPORTIGHT. WALLS

OPENING -~

DIVISION 1 ~ DIVISION 2 Figure 3-5.3(d). Pumps and similar devices handling compressed liquefied flammable gases, indoors with inadequate ventilation and nonvaportight roof and walls. (See NFPA No. 58-1974, Table 3-6.) 505 DEGREE AND EXTENT OF HAZARDOUS LOCATIONS 497-29

5' -L --f-

NON-VAPORTIGHT WALLS; AND ROOF

4' 8, ~ m -IT

[~ DIVISION 1 ~ DIVISION 2 • Figure 3-5.3(e). Pumps and similar devices handling flammable liquids at high flow rates indoors with inadequate ventilation and nonvaportight roof and walls. (See NFPA No. 36-1974, Article 54.)

~ DIVISION 2 Figure 3-5.3(f). Pumps and similar devices handling flammable liquids or compressed liquefied flammable gases at high flow rates, indoors with adequate ventilation. (See NFPA No. 58-1974, Table 3-6.) 506 497-30 CLASS I HAZ. LOCATIONS---ELECT. INSTALLAq'IONS

VAPORTIGHT ROOF AND ~. WALL ~I /,-GRADE .~\v.//2x\\\'~ ////A\\\~)7/

• DIVISION 1 ~ DIVISION 2 Figure 3-5.3(g). Pumps and similar devices handling flammable liquids at high flow rates, or compressed liquefied flammable gases, indoors in small or moderate-sized buildings with inadequate ventilation and with pierced wall or a full wall opemng. (See NFPA No. 58-1974, Table 3-6.)

/-CONTROL VALVES /(SOURCE)

~~O~R~ EXCHANGER DECK

_2 ® I. so, -I/\l~ -50, .i ~---PUMP ALLEY DIVISION 2 SOURCE Figure 3-5.4(a). Process plant handling flammable liquids at high flow rates, outdoors. 507 DEGREE AND EXTENT OF HAZARDOUS LOCATIONS 497-31

, t 1 i z

O O Z z O O I- I.- < < _j _.i _J _.i C- ~F- i 3' RADIUS i ~- i I'° SOLID DECK EXCHANGER LEVEL PIPEWAYS, PIPING f/ WITHOUT VALVES, ][ ~5"~t Ir''l I I II 3' RADIUS ABOVE METERS, OR ,, " i" | / I r I _~L~PuMPSOR BYPASS GASKETED 1~ ' JL ...... IL~mLI~II VALVES WHICHEVER I I ~ ~ L I I I FLANGES ,, ~,~#~//,#,~/x~%,,,,,,,,~--,ll,s HIGHEST t' k-,o,- I \ 1_1o,_..t \\\,u/,<\\\,, GRADE F7"~3 DIVISION 2 u-PUMP ALLEY Figure 3-5.4(b). Process plant handling flammable liquids at moderate flow rates, outdoors. "

SOURCE X ~25'~

GRADE ~ "/~

BELOW GRADE LOCATION . ~o" "l t I SUCH AS SUMP OR TRENCH 100' ~DIVISION 1 F~'~DIVISION 2 ~ ADDITIONAL DIVISION 2 LOCATION EXTRA PRECAUTION WHERE LARGE RELEASE OF VOLATILE PRODUCTS MAY OCCUR. Figure 3-5.4(c). Flammable liquids handled at high flow rates, within an adequately ventilated process area. Source of hazard located near grade. (See API RP 500A-April 1966.) 508 497-32 (:LASS I HAZ, LOCATIONS..--ELECT, INSTALLATIONS

~2S'--~ sou.c,

T GRADE - so' .I 1 . BELOW GRADE LOCATION 100' SUCH AS SUMP OR TRENCH (DIVISION 1) I~DIVlSION 1 F~-~'~DlVlSlON 2 ~ ADDITIONAL DIVISION 2 LOCATION EXTRA PRECAUTION WHERE LARGE RELEASE OF VOLATILE PRODUCTS MAY OCCUR. Figure 3-5.4(d). Flammable liquids handled at high flow rates, with source of hazard located above grade within an adequately ventilated process location. (See API RP 500A-April 1966.)

~ VAPOR

BELOW GRADE LOCATION SUCH AS SUMP OR TRENCH (DIVISION 1) I~DIVISION 1 ~7~OlVISION 2 ~ ADDITIONAL DIVISION2 LOCATION EXTRA PRECAUTION WHERE LARGE RELEASE OF VOLATILE PRODUCTS MAY OCCUR. Apply horizontal clearances of 50 ft from source of vapor or 10 ft beyond perimeter of building, whichever is greater; except beyond unpierced vaportight walls, the zone is classified nonhazardous.

Figure 3-5.4(e). Indoor process area, flammable liquids handled at high flow rates, with source of hazard located above grade within an inadequately ventilated location. (See API RP 500A-April 1966.) 509 DEGREE AND EXTENT OF HAZARDOUS LOCATIONS 497-33

VEN~-/"~3ATRVENTI% 1. BETWEEN /.~ ~3'ANDS'RADDIV2 ~/,J ~/~ f SOLIDFLOOR ~/,~ ~/ ~ k-'PIPEwAYS E'E''NCY 1 D CONTROLVALVES 5' RADIUS/;~. DIV. 2 FROMVENT I~, V/~I////I/lY/~X; I. ~'~-1_8 , 1 DIVISION2 I~--10"--'1 18" 1--10'--'t t CONTROL DIVISION 1 ~DIVISION 2 BUILDING~ Figure 3-5.4(0. Kettles handling flammable liquids, outdoors. Vents dis- charge upward. (See NFPA No. 30-1973, 8635.)

5' RADIUS 3' RADIUS ..---'PARAPET ~"~ "VENT ~ PIPEWAY

5' RADIUS.,~ VENT~ ~ 3' EMERGENCY~~ DUMPTANK "( ) ~~ N II l ~_~ ,.-...... ~.~///..;D'/.~///.///~////A --25' 1

DIVISION I ~ DIVISION 2 Figure 3-5.4(g). Kettles handling flammable liquids at low or moderate flow rates indoors with adequate ventilation. (See NFPA No. 30-1973, Table 5650.) 510 497-34 CLASS 1 I'IAZ. LOCATION~-ELECT. INSTALLATIONS

INERT GAS BLANKET IN ELEVATOR AND BIN

tATOR

DIVISION 1

~ DIVISION 2

Inside the elevator and feed bin when blanketed with inert gas for preventing ignition from other sources, may be classified Division 2. Without inerting it will be classified Division 1. Inside the dryer above the bed shall be Division 1. Normally the air flow would keep the volume below the flammable limit, but due to the unknowns of vapor quantity and flow restrictions in the bed the safe classification is Divison I. Figure 3-5.4(h). Product dryer in totally enclosed system, with adequate ventilation. (See NFPA No. 30.1973, Table 5650.) 511 I)EGREE AND EXTENT OF HAZARDOUS I.OCATIONS 497-35

TANK WITHIN DIKE TANK IN OPEN (UN-DIKED AREA) VENT ,--7 / r 5.

DI KE--~

I"0' 1-10"1 BELOW GRADE LOCATION SUCH AS SUMP OR TRENCH

DIVISION 1 ~ DIVISION 2

If the tank has a floating roof, the zone above the roof and within the tank is Division I. Figure 3-5.5(a). Storage tank outdoors at grade. (See NFPA No. 30-1973, Table VI-9.)

~////~,~'~/~ LIQUID SURFACE

"IY>'\ \ ~ "//I / '

GRADE OF SOLID FLOOR DIVISION 1 ~ DIVISION 2 Figure 3-5.5(b). Open tanks or tanks with hatches normally open. Also, dispensing stations, open centrifuges, plate and frame filters, vacuum filters, and surfaces of open equipment. (See NFPA No. 30-1973, 8635, for open tanks or tanks with hatches normally open. See NFPA No. 30-1973, 5252, for other equipment.) 512 497-36 CLASS 1 HAZ. LOCATIONS---ELECT. INSTALLATIONS

VAPOR RECOVERY FILL LINE

~""'~ 3 ' I'//Z//~,,

• ~ ~ k ~-"k~ • ~ ~'f

DIVISION 2 t

To be used for vessels of similar size in other services solidly piped up and with vapor recovery. (No normal atmospheric vents.)

Figure 3-5.6(a). Tank car and tank truck loading and unloading through closed dome with vapor recovery. (See NFPA No. 30-1973, Table VI-9.)

VAPOR RECOVERY

~,,,. ~ ~%..~- GRADE

...... I/"~ F~LL L,NE "~1"°' RAD,US 10' RADIUS'I ~ DIVISION 2 Figure 3-5.6(b). Tank car and tank truck loading and unloading through bottom with vapor recovery. 513 DEGREE AND EXTENT OF HAZARDOUS LOCATIONS 497-37

DIVISION 1 DIVISION 2 To be used for similar vessels in other service. Solid filling piping and with atmospheric vents. ' Figure 3-5.6(c). Tank car or tank truck loading and unloading through open dome, or through closed dome with atmospheric vent. (See NFPA No. 30-1973, Table V1-9.)

DIVISION 1

DIVISION 2 ~ ~ - . ~ ~ ,--~WNT

• ~//~/Y/J I

~[/~I/////, 97.//////////////"/I~. J~.,- I_ / I. I~] DIVISION I FILL LINE/I0'I-/I RADIUS: ; ~ DIVISION 2

To be used for similar vessels in other service. Solid filling piping and with atmospheric vents. Figure 3-5.6(d). Tank car or tank truck loading and unloading through bottom with atmospheric vent. (See NFPA No. 30-1973, Table VI-9.) 514 497-B8 CLASS 1 HAZ, LOCATIONS--ELECT. INSTALLATIONS

ll, illllltlllllfllllA /

DIVISION 1 " ~ DIVISION 2 Figure 3-5.6(e). Tank car or tank truck loading and unloading compressed flammable gases such as LP-gas. (See NFPA No. 58-1974, Table 3-6.)

18" ///A\\~. I 11 t I, 10' • m ~\¥1iX\l I. • 10' -- "1 I

DIVISION 1 ~ DIVISION 2

Figure 3-5.7(a). Drum and container loading outdoors, or indoors with adequate ventilation. (See NFPA No. 30-1973, Table VI-9.) 515 DEGREE AND EXTENT OF HAZARDOUSLOCATIONS/ 497-39

PIERCED-,,,, WALL

~////AY//////////////A l•JDIVISION 2 Figure 3-5.7(b). Indoor drum storage with no flammable liquid transfer but with opening in wall between the drum storage area and an adjoining classified location. Diagram shows flammable liquid being pumped at moderate flow rate in adjoining location (Figure 3-5.2(c)).

._L _c 18" V//J////J////////-d18" f~8"Y/~//////~/////Z.Isf;I7, LIQUID

DIVISION 2 This does not include open pill that are normally filled with only fl~mmable liquid, such as dip tanks, open mixing tanks, etc. Figure 3-5.8(a). Drainage ditches, separators, and impounding basins that are located outdoors. (See NFPA No. 30-1973, Table VI-9.) 516 497-40 CLASS 1 I'IAZ. LOCATIONS---ELECT.INSTALLATIONS

OVENI

~DIVISION 1 DIVISION 2 Figure 3-5.9(a). Dip tank located indoors with adequate ventilation. (See NFPA No. 34-1974, Chapter 6.)

DIVISION 2

ELEVATION PLAN Figure 3-5.10(a). Paint spray booth, ventilation system interlocked with the spraying equipment so as to make the spraying equipment inoperable when the ventilating system is inoperable. (See NFPA No. 33-1973, 4-7.2) 517 DEGRF.E AND EXTENT OF HAZARDOUS LOCATIONS 497-41

I. 2o "1 I- 20, -I DIVISION 1 ~ DIVISION 2 Figure 3-5.10(b). Dispensing stations, sand mills, open centrifuges, plate and frame filters, change cans, and the surfaces of open equipment. If the liquid used in the operation has a closed cup flash point at or above 100°F (37.8°C) and is not heated above its flash point, general purpose electrical- equipment can be used. (See NFPA No. 35.1971, Article 35, Electrical Equipment.)

SOURCE L~/J/~c3' RAD'US ~ 25' RADIUS

POINT WHERE CONNECTIONS LIQUID HYDROGEN ARE REGULARLY MADE STORAGE CONTAINER

DIVISION 1 ~DIVISION2 Figure 3-5.11(a). Liquid hydrogen systems at consumer sites, located outdoors or in building. (See NFPA No. 52B-1973, Article 49, Electrical Systems.) 518 497-42 CLASS 1 HAZ. LOCATIONS---EI.I'!(.:T. INSTAI.I.ATIONS

~ SOURCE ///.-~\\ .\\Y/# OUTDOOR INDOOR ADEQUATE VENTI LATION

~ DIVISION 2 Figure 3-5.1 l(b). Gaseous hydrogen at consumer sites. (See NFPA No. 50A-1973.)

~ZONE OF INADEQUATE* /~ VENTILATION

i SOURCE OF V

-~-~MAX IMUM OR GRADE--,, I 1~' TO GRADE \ \ \ g/.4-..~. ~15'~

• DIVISION 1 ~"~DIVISION 2 Figure 3-5.11(c). Lighter-than-air gas compressor located within an inadequately ventilated location. (See API RP 500A-April 1966.) 519 REVISIONS TO NFPA NO. 491M 491M-1

PART III

Proposed Amendments of Manual of Hazardous Chemical Reactions

NFPA No. 491M-- 1971

1. Insert the following reactions in their proper alphabetical locations in the body of the text.

ACETALDEHYDE CH3CHO Acetic Acid Acetaldehyde was put in drums previously pickled with acetic acid. The acid caused the acetaldehyde to polymerize, and the drums became hot and vented. MCA Case History 1764 (1971). Phosphorus Isocyanate See PHOSPHORUS ISOCYANATE plus Acetaldehyde.

ACETIC ACID CH3CO.OH Aeetahlehyde See ACETALDEHYDE plus Acetic Acid. 2-Amiaoethanol Mixing acetic acid and 2-aminoethanol inn closed containcr caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Bromine Pentafluoride See BROMINE PENTAFLUORIDE plus Acetic Acid. Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Acetic Acid. Chlorosulfonic Acid Mixing glacial acetic acid and chlorosulfonic acid in a closed container caused tile temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Diallyl Methyl See DIALLYL METHYL CARBINOL plus Carbinol and Ozone Ozone and Acetic Acid. 520 491M-2 REPORTOF COMMITTEE ON CHEMICALSAND EXPLOSIVES

Ethylene Diamine Mixing acetic acid and ethylene diamine in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Ethyleneiminc Mixing glacial acetic acid and ethyleneimine in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Oleum Mixing glacial acetic acid and oleum in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Potassium Tert.- See ACETONE plus Potassium Tert.-Butoxide. Butoxide Phosphorus lsocyanate See PHOSPHORUS ISOCYANATE plus Acetaldehyde. Sodium Hydroxide See SODIUM HYDROXIDE plus Acetic Acid. n-Xylene During thc production of terephthalic acid, n-xylene is oxidizcd in the presence of acetic acid. During these processes, detonating mixtures may be produced. Addition of a small amount of water may largely eliminate the risk of explosion. B. I. Sraer, Himiceskaja promyslennost 46 (10) : 27-30 (1970).

ACETIC ANHYDRIDE CHaCO.OCO.CH3 2-Aminoethanol Mixing acetic anhydride and 2-aminoethanol in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Aniline See ANILINE plus Acetic Anhydride. Boric Acid See BORIC ACID plus Acetic Anh2~dride. Chlorosulfoific Acid Mixing acetic anhydride and chlorosulfonic acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. 521 REVISIONS TO NFPA NO. 491M 491M-3

Ethylene Diamine Mixing acetic ailhydride and ethylene diamine in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Ethylcneimine Mixing acetic anhydride and ethyleneimine in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Hydrochloric Acid Mixing acetic al~hydride and 36% hydrochloric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Hydrofluoric Acid Mixing acetic anhydride and 48.7% hydrofluoric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Hydrogen Peroxide See HYDROGEN PEROXIDE plus Acetic Acid. Nitric Acid Mixing acetic anhydride and 70% nitric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Nitric Acid See NITRIC ACID plus Acetic Anhydride. Oleum Mixing acetic anhydride and oleum in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Perchloric Acid See PERCHLORIC ACID plus Acetic An- hydride. Sodium Hydroxide See SODIUM HYDROXIDE plus Acetic Anhydride. Sulfuric Acid Mixing acetic anhydride and 96% sulfuric acid in a closed container caused the temperature and pressure to increase.. Flynn and Rossow (1970). See Note under complete reference. 522 401M-4 REPORTOF COMMITTEE ON CHEMICALS AND EXPLOSIVES

ACETONE CH3COCH3 Potassium Tert.- Ignition occurs when potassium t-butoxide Butoxide reacts with the following: acetone, ethyl methyl ketone, methyl isobutyl ketone, methanol, ethanol, n-propanol, isopropanol, ethyl acetate, n-butyl acetate, n-propyl formate, acetic acid, sulfuric acid, methylene chloride, chloroform, carbon tetrachloride, epichlorohydrin, dimethyl carbonate, and diethyl sulfate. MCA Case History 1948 (1973). Thiodiglycol and See THIODIGLYCOL plus Hydrogen Peroxide Hydrogen Peroxide and Acetone.

ACETONITRILE CHaCN Chlorosulfonic Acid Mixing acetonitrile and chlorosulfonic acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Erbium Perchlorate In the preparation of anhydrous erbium perchlorate an acetonitrile extraction was made. During the final stages of the procedure a glossy material was formed that exploded when scratched with a spatula. It was concluded that acetonitrile was trapped in the glossy erbium perchlorate and that this material was shock- sensitive as are many organic-containing perchlorates. J. Chem. Edu. 50 (6): A336-7 (1973). 01eum Mixing acetonitrile and oleum in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Sulfuric Acid Mixing acetonitrile and 96% sulfuric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference.

ACETYLENE CH!CH Nitric Acid See NITRIC ACID plus Acetylene. 523 REVJSIONS TO NFPA NO. 491M 491M-5

2-ACETYL-3-METHYLTHIOPHENONE SC(CO.CH3) :C(CH3)CO.CH2 L I (self-reactive) A vacuum distillation of 2-acetyl-3-methylthiophenone was being performed on a laboratory bench when suddenly there was an explosion. MCA Guide for Safety, Appendix 3 (19.72).

ACIDS Acrolein See ACROLEIN plus Sulfur Dioxide. Benzyl Alcohol Benzyl alcohol containing acidic constituents and dissolved iron was found to polymerize with a rapid temperature increase when heated in excess of 100° C. Amines, pyridene, and alkali hydroxides act as inhibitors and prevent polymerization. Chem. Abst. 77:7816w (1972). Lithium Aluminum See LITHIUM ALUMINUM HYDRIDE Hydride plus Water. Nickel Nitride See NICKEL NITRIDE plus Acids. Sodium Ozonate See SODIUM OZONATE plus Acids. Thorium Phosphide See THORIUM PHOSPHIDE plus Acids.

ACROLEIN CH,~:CHCHO Acids See ACROLEIN plus Sulfur Dioxide. Alkalis See ACROLEIN plus Sulfur Dioxide. Amines See ACROLEIN plus Sulfur Dioxide. 2-Aminoethanol Mixing acrolein and 2-aminoethanol in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Ammonium Hydroxidc Mixing acroleia and 28% ammonium hydroxide in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Chlorosulfonic Acid Mixing acrolein and chlorosulfonic acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. 524 491M-6 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

Ethylene Diamine Mixing acrolein and ethylene diamine in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Ethyleneimine Mixing acrolein and ethyleneimine in a closed container caused the temperature and~ pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Nitric Acid Mixing acrolein and nitric 70% acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Oleum Mixing acrolein and oleum in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Sodium Hydroxide See SODIUM HYDROXIDE plus Acrolein. Sulfur Dioxide Acrolein polymerizes with release of heat on contact with minor amounts of acids (including sulfur dioxide), alkalis, volatile amines, salts, thiourea,-oxidants (air) and on exposure to light and heat. BCISC 44:174 (1973). Sulfuric Acid Mixing acrolein and 96% sulfuric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossab) (1970). See Note under complete reference. Thiourea See ACROLEIN plus Sulfur Dioxide.

ACRYLIC ACID H2C :CHCO.OH 2-Aminoethanol Mixing acrylic acid and 2-aminoethan01 in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Ammonium Hydroxide Mixing acrylic acid and 28% ammonium hydroxide in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. 525 REVISIONS TO NFPA NO. 491M 491M-7

Chlorosulfonic Acid Mixing acrylic acid and chlorosulfonie acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Ethylene Diamine $~ixing acrylic acid and ethylene diamine in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Ethyleneimine Mixing acrylic acid and ethyleneimine in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Oleum MLxing acrylic acid and oleum in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference.

ACRYLONITRILE CH2:CHCN 2-Aminoethanol Mixing acrylonitrile and 2-aminoethauol in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Chlorosulfonic Acid Mixing acrylonitrile and chlorosulfonie acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Ethylene Diamine MiXing acrylonitrile and ethylene diamine in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Oleum Mixing acrylonitrile and oleum in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Sulfuric Acid Mixing acrylonitrile and 96% sulfuric acid in a closed container caused the temperature and . pressure to increase. Flynn and Rossow (1970). See Note under complete reference. 526 491M-8 REPORTOF COMMITTEE ON CHEMICALS AND EXPLOSIVES

ACYL HYPOFLUORITES (self-reactive See PERFLUOROPROPIONYL FLUORIDE plus Fluorine. .t

ALCOHOLS Barium Perchlorate See BARIUM PERCHLORATE plus Alcohols. Lithium Aluminum See LITHIUM ALUMINUM HYDRIDE Hydride plus Water. Nitrogen Tetroxide See NITROGEN TETROXIDE plus Alcohols.

ALKALI METALS Hydrazine and See HYDRAZINE plus Alkali Metals and Ammonia Ammonia.

ALKENES Fluorine See FLUORINE plus Alkenes.

ALKYL BENZENES Fluorine See FLUORINE plus Alkyl Benzenes.

ALKYLPHOSPHINES Chlorine See CHLORINE plus Alkylphosphines.

ALLYL ALCOHOL CH2 :CHCH~OH Chlorosulfonic Acid Mixing allyl alcohol and chlorosu]fonie acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Diallyl Phosphite and See DIALLYL PHOSPHITE plus Allyl Phosphorus Alcohol and Phosphorus Trichloride. Trichloride Nitric Acid Mixing allyl alcohol and 70% nitric acid in a closed container caused the temperature and- pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Oleum Mixhlg allyl alcohol and oleum in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Sulfuric Acid Mixing allyl alcohol and 96% sulfuric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. 527 REVISIONS TO NFPA NO. 491M 491M-9

ALLYL CHLORIDE CH2:CHCH~CI Aluminum Chloride See SULFURIC ACID plus Allyl Chloride. Chlorosulfonic Acid Mixing allyl chloride and chlorosulfonic acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Ethylene Diamine Mixing allyl chloride and ethylene diamine in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Ethyleneimine Mixing allyl chloride and ethyleneimine in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Ferric Chloride See SULFURIC ACID plus Allyl Chloride. Lewis-Type Catalysts See SULFURIC ACID plus Allyl Chloride. Nitric Acid Mixing allyl chloride and 70% nitric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Oleum Mixing allyl chloride and oleum ill a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Sodium Hydroxide See SODIUM HYDROXIDE plus Allyl Chloride. Sulfuric Acid Mixing allyl chloride and 96% sulfuric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. See SULFURIC ACID plus Allyl Chloride. Ziegler-Typc Catalysts See SULFURIC ACID plus Allyl Chloride.

ALUMINUM AI Antimony Trichloride See ALUMINUM plus Phosphorus Triehloride. Arsenic Trichloride See ALUMINUM plus Phosphorus Trichloride. Bromine Mellor 5:209 (1946-1947). 528 491M-10 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

Carbon Disulfide Powdered aluminum burns in the vapor of. carbon disulfide, sulfur dioxide, sulfur dichloride, nitrous oxide, nitric oxide, or nitrogen peroxide. Mellor 5" 209-212 (1946-1947). Chlorinc Trifluoride In the presence of carbon, the combination of chlorine trifluoride with aluminum, copper, lead, magnesium, silver, tinor zinc results in a violent reaction. Mellor 2, Supp. 1: (1956). See also CHLORINE TRIFLUORIDE plus Elements. Chromic Anhydride A violent reaction or flaming is likely in the reaction of chromic anhydride and aluminum powder. Mellor 11:237 (1946-1947). Nitric Oxide See ALUMINUM plus Carbon Disulfide. Nitrogen Peroxide See ALUMINUM plus Carbon Disulfide. Nitrosyl Chloride Aluminum is attacked by nitrosyl chloride when cold. MeUor 5:212 (1946-1947). Nitrous Oxide See ALUMINUM plus Carbon Disulfide. Oxygen A lecturer was demonstrating the ignition of powdered aluminum mixed with liquid oxygen when the mixture exploded. Seventecn persons were injured. This experiment, which is described in several places as a lecture demon- stration, has been carried out successfully hundreds of times but there have been a few explosions when the conditions were just right. Chem. Eng. News 35(25): 90 (June 17, 1957). Perfor,nic Acid Powdered aluminum decomposes performic acid violently. Berichte 48:1139 (1915). Phosgene See ALUMINUM plus Phosphorus Trichloride. Phosphorus Trichloride Powdered alumi,mm bums in the vapor of phosphorus trichloride, antimony trichloride, arsenic trichloride, and phosgene. Mellor 5:214 (1946-1947). Sodium Carbide See MERCURY plus Sodium Carbide. Sodium Hydroxide Aluminum reacts vigorously in sodium hydroxide. Mellor 5:207 (1946-1947). Sulfur Dichloride See ALUMINUM plus Carbon Disulfide. Sulfur Dioxide See ALUMINUM plus Carbon Disulfide. 529 REVISIONS TO NFPA NO. 491M 491M-11

ALUMINUM BROMIDE A1Br3 Potassium See POTASSIUM plus Aluminum Bromide. Sodium See SODIUM plus Aluminu m Bromide.

ALUMINUM CHLORIDE A1CI3 Allyl Chloride See SULFURIC ACID plus Allyl Chloride. Ox~ygen Difluoride See OXYGEN DIFLUORIDE plus Aluminum Chloride. Potassium See POTASSIUM plus Aluminum Bromide. Sodium See SODIUM plus Aluminum Bromide. Water This salt dissolves in water with hissing and much heat. Mellor 5:314 (1946-1947).

ALUMINUM FLUORIDE A1F3 Potassium See POTASSIUM plus Aluminum Bromide. Sodium See SODIUM plus Aluminum Bromide.

ALUMINUM HYPOPHOSPHITE A1 (PH202)3 Air Aluminum hypophosphite releases spontaneously flammable phosphine at about 220 ° C. Mellor 8, Supp. 3:623 (1971).

ALUMINUM OXIDE AlcOa Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Alu- minum Oxide.

ALUMINUM TETRAAZIDOBORATE AI[B(Na)4]3 (self-reactive) This compound is very explosive on shock. Mellor 8, Supp. 2:2 (1967).

AMINES RNH~ Acrolein See ACROLEIN plus Sulfur Dioxide.

2-AMINOETHANOL NH~CH2CH2OH Acetic Acid See ACETIC ACID plus 2-Aminoethanol. Acetic Anhydride See ACETIC ANHYDRIDE plus 2-Amino- ethanol. Acrolein See ACROLEIN plus 2-Aminoethanol. Acrylic Acid See ACRYLIC ACID plus 2-Aminoethanol. Acrylonitrile See ACRYLONITRILE plus 2-Aminoethanol. Chlorosulfonic Acid Mixing 2-Aminoethanol and chlorosulfonic acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. 530 491M-12 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

Epichlorohydrin Mixing 2-aminoethanol and epichlorohydrin in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Hydrochloric Acid Mixing 2-aminoethanol and.36% hydrochloric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Hydrofluoric Acid Mixing 2-aminoethanol and 48.7% hydrofluoric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Mesityl Oxide See MESITYL OXIDE plus 2-Aminoethanol. Nitric Acid Mixing 2-aminoethanol and 70% nitric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Oleum Mixing 2-aminoethanol and oleum in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Propiolactone Mixing 2-aminoethanol and propiolactone (BETA-) (BETA-) in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Sulfuric Acid Mixing 2-aminoethanol and 96% sulfuric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Vinyl Acetate Mixing 2-aminoethanol and vinyl acetate in a closed container caused the .temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference.

AMINOGUANIDINE NITRATE CH6Nd"HNO3 (self-reactive) Aminoguanidine nitrate in water solution exploded violently while being evaporated to dryness in vacuo on the steam bath. H. Koop- man, Chem. Weekblad 53: 97, 98 (1957). 531 REVISIONS TO NFPA NO. 491M 491M-13

AMMONIA NH3 l, Bromine Pentafluoride See BROMINE PENTAFLUORIDE plus Acetic Acid. Chloric Acid See ANTIMONY plus Chloric Acid. Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Am- monia. Chromic anhydride See CHROMIC ANHYDRIDE plus Am- monia. Ethylene Dichloride Liquid ammonia and ethylene dichloride can cause an explosion when mixed. Mukerjee (1970). Hydrazine and Alkali See HYDRAZINE plus Alkali Metals and Metals Ammonia. Hydrogen Bromide See HYDROGEN BROMIDE plus Ammonia. Magnesium Perchlorate See MAGNESIUM PERCHLORATE plus Ammonia. Nitrogen Peroxide See NITRIC OXIDE plus Ammonia. Oxygen Difluoride See OXYGEN DIFLUORIDE plus Ammonia. Phosphorus Pentoxide See PHOSPHORUS PENTOXIDE plus Am- monia. Potassium and Arsine See POTASSIUM plus Arsine and Ammonia. Potassium and See POTASSIUM plus Phosphine and Am- Phosphine monia. Potassium and Sodium See POTASSIUM plus Sodium Nitrite and ")l: Nitrite Ammonia. Sodium and Carbon See SODIUM plus Carbon Monoxide and Monoxide Ammonia. Sulfur See SULFUR plus Ammonia. Sulfur Dichloride See SULFUR DICHLORIDE plus Ammonia. AMMONIUM ACETATE CH3COONH4 Sodium Hypochlorite See SODIUM HYPOCHLORITE plus Am- monium Acetate. AMMONIUM AZIDE NH4N5 (self-reactive) Ammonium azide decomposes at 160 ° C. Mellor 8, Supp. 2:43 (1967). AMMONIUM BROMIDE NH4Br Bromine Trifluoride See BROMINE TRIFLUORIDE plus Am- monium Bromide. Iodinc Heptafluoride See IODINE HEPTAFLUORIDE plus Am- monium Bromide. Potassium See POTASSIUM plus Ammonium Bromide. 532 491M-14 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

AMMONIUM CARBONATE (NH4)2CO3 Sodium Hypochlorite See SODIUM HYPOCHLORITE plus Am- monium Acetate.

AMMONIUM CHLORATE NH4C103 (self-reactive) The solid is an explosive compound. Solutions may decompose violently if much solid phase is present. Mellor 2, Supp. 1:591 (1956).

AMMONIUM CHLORIDE NH4C1 Ammonium Nitrate See AMMONIUM NITRATE plus Am- monium Chloride. Bromine Trifluoride See BROMINE TRIFLUORIDE plus Am- monium Bromide. Iodine Heptafluoride See IODINE HEPTAFLUORIDE plus Am- monium Bromide.

AMMONIUM CHLOROCUPRATE' (NH4)2CuC14 Potassium See POTASSIUM plus Aluminum Bromide. Sodium See SODIUM Plus Aluminum Bromide.

AMMONIUM DICHROMATE (NH4)2Cr~07 (self-reactive) Ammonium dichromate decomposes vigorously with luminescence around 200 ° C. It is feebly explosive if confined. Mellor 11:324 (1946-1947).

AMMONIUM HYDROXIDE NH,OH Acrolein . See ACROLEIN plus Ammonium Hydroxide. Acrylic Acid See ACRYLIC ACID plus Ammonium Hy- droxide.. Chlorosulfonic Acid See CHLOROSULFONIC ACID plus Am- monium Hydroxide. Fluorine See FLUORINE plus Ammonium Hydroxide. Hydrochloric Acid See HYDROCHLORIC ACID plus Am- monium Hydroxide. Hydrofluoric Acid See HYDROFLUORIC ACID plus Am- monium Hydroxide. Iodine See IODINE plus Ammonium Hydroxide. Nitric Acid See NITRIC ACID plus Ammonium Hy- droxide. Oleum See OLEUM plus Ammonium Hydroxide. Propiolactone (BETh) See PROPIOLACTONE (BETA) plus Am-' monium Hydroxide. Propylene Oxide See PROPYLENE OXIDE plus Ammonium Hydroxide. 533 REVISIONS TO NFPA NO. 491M 491M-15

Silver Permanga'nate See SILVER PERMANGANATE plus Am- monium Hydroxide. Sulfuric Acid See SULFURIC ACID plus Ammonium HY- droxide.

AMMONIUM HYPOPHOSPHITE NH~PH~02 (self-reactive) Ammonium hypophosphite liberates spontaneously flammable phosphine at about 240 ° C. Mellor 8:880 (1946-1947).

AMMONIUM IODIDE NH4I Bromine Trifluoride See BROMINE TRIFLUORIDE plus Am- monium Bromide. Iodine Heptafluoride See IODINE HEPTAFLUORIDE plus Am- monium Bromide. Potassium See POTASSIUM plus Ammonium Bromide.

AMMONIUM NITRATE NH4NO3 Ammonium Chloride The decomposition of ammonium nitrate in the presence of ammonium chloride (0.1%) becomes violent around 175° C. The gases liberated contain chlorine. Pascal 10:216 (1931-1934). CHLORIDES See AMMONIUM NITRATE; plus Am- monium Chloride. Copper See COPPE]~ plus Ammonium Nitrate. Sodium Hypochlorite See SODIUM HYPOCHLORITE plus Am- monium Acetate. Sodium Perchlorate See SODIUM PERCHLORATE plus Am- monium Nitrate.

AMMONIUM OSMIAMATE NH4OsN03 (self-reactive) AmmoP.ium osmiamate decomposes explosively at 150° C. Mellor 15:727 (1946-1947).

AMMONIUM OXALATE (NH~OOC-)2 Sodium Hypochlorite See SODIUM HYPOCHLORITE plus Am- monium Acetate.

AMMONIUM PERCHLORATE NH4CIO4 (self-reactive). Ammonium perchlorate decomposes at 130°C and explodes at 380 ° C. Mellor 2, Supp. 1:608 (1956). 534 491M-16 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

AMMONIUM PHOSPHATE NH4H2P04 Sodium Hypochlorite See SODIUM HYPOCHLORITE plus Am- monium Acetate.

AMMONIUM SALTS Potassium Chlorate See POTASSIUM CHLORATE plus Am- momum Salts.

AMMONIUM TETRACHROMATE (NH4)2Cr4013 (self-reactivc) Ammonium tetrachromate decomposes suddenly at 175 ° C. Mellor 11:352 (1946-1947).

AMMONIUM TRICHROMATE (NH4)2Crs010 (self-reactive) Ammomum trichromate detonates at about 190 ° C. Mellor 11:350 (1946-1947).

AMMONIUM THIOCYANATE NH4SCN Lead Nitrate An explosion of guanidiue nitrate demolished an autoclave built to withstand 50 atmospheres, in which it was being madc from ammonium thiocyanate and lead nitr~te. C. Schopf and H. Klapproth. Angew. Chem. 49:23 (1936).

AMMONIUM THIOSULFATE NH4S~Oa Sodium Chlorate See SODIUM CHLORATE plus Amnmnium Thiosulfate.

AMMONIUM TRIPERCHROMATE (NH4)aCrO04 (self-reactive) Amlnonium triperchromate explodes from percussion or if heated just to 50 ° C. Mellor 11:356 (1946-1947). SulfuricAcid Contact between these compounds results in an explosion. Mellor 11:356 (1946-1947).

ANILINE C6H~NH2 Acetic Anhydride Mixing aniline and acetic anhydride in a closed container caused the temperature aM pressure to iucrease. Flynn and Rossow (1970). See Note raider complete reference. 535 ]REVISIONS TO NFPA NO. 491M 491M-17

Chlorosulfoni0 Acid Mixing aniline and chlorosulfonic acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under coin- pletc reference. Oleum Mixing aniline and oleum in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Perchromates See PERCHROMATES plus Atfiline. Performic Acid See PERFORMIC ACID plus Alfiline. Propiolactone (~ETA-) Mixing aniline and propolactone (BETA-) in a closcd container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Silver Perehlorate See SILVER PERCHLORATE plus Toluene. Silver Perchloratc See SILVER PERCHLORATE plus Acetic Acid. Sulfuric Acid Mixing aniline and 96% sulfuric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference.

ANTIMONY Sb Chloric Acid Explosions of chloric acid have been due to the formation of explosive compounds with antimony, bismuth, ammonia, ~nd organic matter. Chem. Abst. 46: 2805e (1952). Chlorine Trifluoride Chlorine trifluoridc reacts vigorously with antimony, arsenic, osmium, phosphorus, potassium, rhodium, selenium, silicon, sulfur, tellurium, or tungsten, producing flame. Mellor 2, Supp. l: 156 (1956). Nitric Acid The reaction of finely divided antinmny and lfitric acid can be violent. Pascal 10:504 (1931-1934).

ANTIMONYL CHLORIDE O2SbC13 Bromine Trifluoride See BROMINE TRIFLUORIDE plus Anti- mony Trioxide.

ANTIMONYL PERCHLORATE SbOCI04 (self-reactive) This chemical decrepitates when heated above 60 ° C. MeUor 2, Supp. 1:613 (1956). 536 491M-18 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

ANTIMONY TRIBROMIDE SbBra Potassium See POTASSIUM plus Aluminum Bromide. Sodium See SODIUM plus Aluminum Bromide.

ANTIMONY TRICHLORIDE SbCI~ Aluminum See ALUMINUM plus Phosphorus Tri- chloride. Potassium See POTASSIUM plus Aluminum Bromide. Sodium See SODIUM plus Aluminum Bromide.

ANTIMONY TRIIODIDE SbI~ Potassium See POTASSIUM plus Aluminum Bromide. Sodium See SODIUM plus Aluminum Bromide.

ANTIMONY TRIOXIDE Sb203 Bromine Trifluoride See BROMINE TRIFLUORIDE plus Anti- mony Trioxide.

ANTIMONY TRISULFIDE Sb2S3 Hydrogen Peroxide Hydrogen peroxide resets vigorously with antimony trisulfide, arsenic trisulfide, cupric sulfide, lead sulfide, molybdenum disulfide, and ferrous sulfide. Mellor 1:937 (1946-1947).

ARSENIC As Chlorine Trifluoride See ANTIMONY plus Chlorine Trifiuoride. Lithium See LITHIUM plus Arsenic.

ARSENIC TRICHLORIDE AsC13 Aluminum See ALUMINUM plus Phosphorus Triehloride. Aluminum Fluoride See SODIUM plus Aluminum Bromide. Ammonium -See SODIUM plus Aluminum Bromide. Chloroeupr~te Antimony Tribromide See SODIUM plus Alutninum Bromide. Antimony Trichloride See SODIUM plus Aluminum Bromide. Antimony Triiodide See SODIUM plus Aluminum Bromide. Arsenic Trichloride See SODIUM plus Aluminum Bromide. Arsenic Triiodide See SODIUM. plus Aluminum Bromide. Potassium See POTASSIUM plus Aluminum Brohaide. Sodium See SODIUM plus Aluminum Bromide.

ARSENIC TRIFLUORIDE AsF3 Phosphorus Trioxide This reaction is very violent. MeUor 8, Supp. 3:382 (1971). 537 REVISIONS TO NFPA NO. 491M 491M-19

ARSENIC TRIIODIDE Asl3 Potassium See POTASSIUM plus Alumimun Bromide. Sodium See SODIUM plus Aluminum Bromide.

ARSENIC TRIOXIDE As203 Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Arselfic Trioxide. Oxygen Difluoride See OXYGEN DIFLUORIDE plus Aluminum Chloride.

ARSENIC TRISULFIDE As2S3 Hydrogen Peroxide See ANTIMONY TRISULFIDE plus Hydro- gen Peroxide.

ARSINE AsH3 Potassium and See POTASSIUM plus Arsine and Ammonia. Ammonia

4-AZIDO-N,N-DIETHYLANILINE NNNC6H4N(C2Hs)2 (self-reactive) An attempt to distill this compound resulted in violent decomposition. NSC Newsletter, R & D Sec. (July 1973).

AZIDOFLUORINE N3F (self-reactive) See FLUORINE AZIDE. (self-reactive).

a,fi-AZODIISOBUTYRONITRILE [NcC(CH3)2N :]2 (self-reactive) An explosion occurred when a solution of afi-azodiisobutyronitrile in acetone was concentrated in a glass-lined steam-jacketed vessel. P. J. Carlisle, Chem. Eng. News 27:150 (1949).

BARIUM AZIDE Ba(Nz)2 (self-reactive) Barium t~zide decomposes at 275 ° C. It is explosively uttstable. Mellor 8, Supp. 2:43 (1967).

BARIUM CHLORATE Ba(CI03)3 Sulfur See SULFUR plus Barium Chlorate.

BARIUM CHLORIDE BaCI2 Bromine Trifluoride See BROMINE TRIFLUORIDE plus Barium Chloride. 2-Furan Percarboxylic See 2-FURAN PERCARBOXYLIC ACID Acid (self-reactive). 538 491M-20 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

BARIIJM OSMIAMATE Ba(OsN03)2 (self-reactive) Barium osmiamate detonates at 150°C. Mellor 15:728 (1946-1947).

BARIUM PERCHLORATE Ba(CIO4),.H20 Alcohols Reflux heating of an alcohol and barium perchlorate yields a perchloric ester, all of which are highly explosive. Kirk and Othmer, Second Ed. 5:75 (1963).

BENZALDEHYDE C6HsCHO Performic Acid See PERFORMIC ACID plus Benzaldehyde. BENZENE C6H8 Bromine Pentafluoride See BROMINE PENTAFLUORIDE plus Acetic Acid. Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Ben- zene. Chromic Anhydride See CHROMIC ANHYDRIDE plus Benzene.

Perchlorates See PERCHLORATES plus Benzene. Silver Perchlorate See SILVER PERCHLORATE plus Acetic Acid. Silver Perchlorate See SILVER PERCHLORATE plus Toluene.

BENZENEDIAZONIUM 2-CARBOXYLATE HYDROCHLORIDE N i N-C6H4-2-CO~'HCI (self-reactive) An explosion occurred during the transfer of dry crystals. H. D. Embry, Chem. Eng. News 49 (30): 3 (1971). R.: M. Stiles et al, J. Am. Chem. Soc. 85, p. 1795 (1963). C. A. Matuszak, Chem. Eng. News 49 (24): 39 (1971).

BENZOYL CHLORIDE C6H~COC1 Sodium Azide and See SODIUM AZIDE plus Benzoyl Chloride Potassium and Potassium Hydroxide. Hydroxide

BENZOYL PEROXIDE (CeHsCO)20~ N,N-Dimethylaniline Explosive decomposition occurred when finely ground benzoyl peroxide was allowed to react with N,N-dimethylaniline by breaking an ampoule containing 0.5 grams of dimethylani- lille in aa autoclave. L. Homer and C. Betzel, Chem. Ber. 86: 1071-72 (1953). 539 REVISIONS TO NFPA NO. 491M 491M-21

Lithium Aluminum An attempted reduction of benzoyl peroxide Hydride with lithium aluminum hydride resulted in an explosion. D.A. Sutton, Chem. & Ind. 1951:272 (1951). BENZYL ALCOHOL C6H~CH20H Acids See ACIDS plus Benzyl Alcohol.

BERYLLIUM Be Lithium See LITHIUM plus Vanadium.

BISMUTH Bi Chloric Acid See ANTIMONY plus Chloric Acid. Perchloric Acid The preparation of a salt from these two chemicals is dangerous. MeUor 2, Supp. 1:613 (1956). BISMUTH PENTOXIDE Bi20~ Bromine Trifluoride See BROMINE TRIFLUORIDE plus Bis- muth Pentoxide. BISMUTH TRIBROMIDE BiBr3 Potassium See POTASSIUM plus Aluminum Bromide. Sodium See SODIUM plus Aluminum Bromide.

BISMUTH TRICHLORIDE BiCI3 Potassium See POTASSIUM plus Aluminum Bromide. Sodium See SODIUM plus Aluminum Bromide.

.BISMUTH TRIIODIDE BiI3 Potassium See POTASSIUM plus Aluminum Bromide. Sodium See SODIUM plus Aluminum Bromide.'

BISMUTH TRIOXIDE Bi~Oa ChlorineTrifluoride See CHLORINE TRIFLUORIDE plus Ar- senic Trioxide.

BORANE-PHOSPHORUS TRIFLUORIDE COMPOUND H3BPF3 (self-reactive) See PHOSPHORUS TRIFLUORIDE plus Diborane. BORIC ACID B(OH)a Acetic Anhydride During an attempt to make triacetyl borate, a mixture of boric acid and acetic anhydride exploded when heated to 58-60 ° C. M. L. Lerner. Chem. Eng. News. 51: (34) (Aug. 20, 1973). Potassium See POTASSIUM plus Boric Acid. 540 491M-22 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

BORON B Bromine Boron ignites in bromine vapor at 700 ° C. MeUor 5:15 (1946-1947). Chlorine Boron ignites in chlorine at 410 ° C. MeUor 5:15 (1946-1947). Cupric Oxide Boron reacts violently with cupric oxide after warming, melting glass tubing. MeUor 5:17 (1946-1947). Potassium Chlorate The reaction of boron and fused potassium chlorate is vigorous. Mellor 5:15 (1946-1947). Sulfur A mixture of boron and sulfur becomes incandescent at 600 ° C. Mellor 5:15 (1946-1947).

BORON BROMODIIODIDE BBrI~ Water Boron bromodiiodide hydrolyzes violently. Mellor 5:136 (1946-1947).

BORON DIBROMOIODIDE BBr2I Water Boron dibromoiodide hydrolyzes violently. Mellor 5:136 (1946-1947).

BORON TRIAZIDE B(N3)3 (self-reactive) Boron triazide, lithium boroazide, and silicon tetraazide and some of their intermediates are extremely sensitive and explosive. Egon Wibergand Horst Michaud, Z. Natur- ]orsch. 9b: 497-500 (1954).

BORON TRIBROMIDE BBr3 Potassium See POTASSIUM plus Boron Tribromide. Sodium See SODIUM plus Aluminum Bromide.

BORON TRICHLORIDE BC13 Nitrogen Peroxide Boron trichloride reacts energetically with nitrogen peroxide, phosphine, or fat and grease. Mellor 5:132 (1946-1947). Organic Matter See BORON TRICHLORIDE plus Nitrogen Peroxide. Oxygen See OXYGEN plus Boron Trichloride. 15hosphine See BORON TRICHLORIDE plus Nitrogen Peroxide. 541 REVISIONS :TO NFPA NO. 491M 491M-23

BORON TRIFLUORIDE BF~ CMcium Oxide See CALCIUM OXIDE plus Boron Trifluoride.

BORON TRIiODIDE BI3 Carbohydrates See BORON TRIIODIDE plus Ethers. Ethers Boron triiodide and ethers or carbohydrates react vigorously. Mellor 5:136 (1946-1947). •Phosphoryl Chloride See PHOSPHORYL CHLORIDE plus Boron Triiodidc.

BROMINE Br2 Boron See BORON plus Bromine. Chlorotrifltmroethylene See CHLOROTRIFLUOROETHYLENE plus and Oxygen Bromine and Oxygen. Dimethyl Formamide The use of dimcthyl formamide as a solvent in one of the catalysis reactions of olefii~s and bromine resulted in the operation of a rupture disk on an autoclave. The investigation indicated that there was a highly exothermic reaction between dimethyl formamide and bromine. In one instance mixing 40 cc of bromine and 150 ce of dimethyl formamide resulted in an increase of temperature to above 100°C and an increase in pressure to above 2000 psi. H. A. Tayim and M. Absi, Chem. & Ind. p. 347 (April 21, 1973). Isobutyrophenone 13romine had been added dropwise at 21-31 ° C to a solution of isobutryrophenone in carbon tetrachloride. The fask was then packed in ice. After 15 minutes, the flask exploded. MCA Guide for Safety, Appendix 3 (1972). Methyl Alcohol A violent cxothermie reaction of these materials occurred in a measuring cylinder. MCA Case History 1863 (1972). Nickel Carbonyl The reaction betweei~ these liquids proceeds with explosive violence. Mellor 2, Supp. 1:716 (1956). Olefins Sec BROMINE plus Dimethyl Formamide. Oxygen Difluoride A mixture of oxygen difluorkle and bromine or iodine explodes on gentle warming. Mellor 2, Supp. 1 : 192 (1956). Ozone See OZONE plus Bromine. Phosphorus See also PHOSPHORUS plus Chlorine. Pot'~ssium MeUor 2, Supp. $: 1559. 542 491M-24 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

Rubidium Carbide This carbide burns in bromine gas. Mellor 5:848 (1946-1947). Strontium Phosphide Mixtures of these, materials ignite at about 170 ° C: Mellor 8:841 (1946-1947). Tin See TIN plus Bromine.

BROMINE AZIDE N3Br (self-reactive) Spontaneous explosions have been observed with this compound. Mellor 8, Supp. 2:50 (1967) Mellor 8 : 336 (1946-1947).

BROMINE MONOFLUORIDE BrF Organic Matter See BROMINE MONOFLUORIDE plus water. Water Halogen fluorides react, violently with water and organic compounds. Mellor 2, Supp..l: 147 (1956). See also CHLORINE TR.IFLUORIDE plus Elements.

BROMINE PENTAFLUORIDE BrF~ Acetic Acid In reactions between bro.mine pentafluoride and acetic acid, ammonia, benzene, cellulose (in paper), ethyl alcohol, organic matter such as grease or wax, hydrogen sulfide, or methane, fire and explosions are likely. MeUor 2, Supp. 1:172 (1956). Ammonia See BROMINE PENTAFLUORIDE plus Acetic Acid. Benzene See BROMINE PENTAFLUORIDE plus Acetic Acid. Cellulose See BROMINE PENTAFLUORIDE plus Acetic Acid. Chlorine See CHLORINE plus Bromine Pentafluoride Ethyl Alcohol Sec BROMINE PENTAFLUORIDE plus Acetic Acid. Hydrogen Sulfide See BROMINE PENTAFLUORIDE plus Acetic Acid. Iodine See IODINE plus Bromine Pentafluoride. Metallic Halides See BROMINE PENTAFLUORIDE plus Metal Oxides. Metal Oxides Bromine pentafluoride reacts violently with metal oxides and metallic halides. Mellor 2, Supp. 1:172 (1956). Metals See METALS plus Bromine Pentafluoride. 543 REVISIONS TO NFPA NO. 491M 491M-25

Methane See BROMINE PENTAFLUORIDE plus Acetic Acid. Nitric Acid Bromine pentafluoride reacts violently with strong nitric acid or strong sulfuric acid. Mellor 2, Supp. 1:172 (1956). Organic Matter See BROMINE PENTAFLUORIDE plus Acetic Acid. See also BROMINE MONO- FLUORIDE plus Water. Sulfuric Acid See BROMINE PENTAFLUORIDE plus Nitric Acid. Water The reaction between bromine pentafluoride and water is very violent. Mellor 2, Supp. 1:172 (1956). See also BROMINE MONOFLUORIDE plus Water.

BROMINE TRIFLUORIDE BrFa Ammonium Bromide Bromine trifluoride reacts explosively with the following: ammonium bromide, ammonium chloride, ammonium iodide. Mellor 2, Supp. 1:165 (1956). Ammonium Chloride See bROMINE TR[FLUORIDE plus Am- monium •Bromide. Ammolfium Iodide See BROMINE TRIFLUORIDE plus Am- monium Bromide. Antimonyl Chloride See bROMINE TRIFLUORIDE plus Anti- mony Trioxide. Antimony Trioxide Bromine trifluoride produces a violent reaction with antimony trioxide, more violent with antimonyl chloride. Mellor 2, Supp. 1:166 (1956). Barium Chloride Bromine trifluoride rapidly attacks the following salts: barium chloride, cadmium chloride, calcium chloride, cesium chloride, lithium chloride, rubidium chloride, silver chloride. MeUor 2, Supp. 1:165 (1956). Bismuth Pe~ltoxide Bromine trifluoride and bismuth pentoxide, manganous iodate, niobium pentoxide, or tantalum pentoxide react vigorously. Mellor 2, Supp. 1: 166, 173 (1956). Cad,nium Chloride Sec BROMINE TRIFLUORIDE plus Barium Chloride. Calcium Chloride See BROMINE TRIFLUORIDE plus Barium Chloride. 544 491M-26 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

Carhon Monoxide Bromine trifluoride and carbon monoxide react explosively at high temperatures or con- ce~trations. Mellor 2, Supp. 1:166 (1956). Carbon Tetrachloride Bromine trifluoride and carboa tetrachloride react vigorously. MeUor 2, Supp. 1:167 (1956). Carbon Tetraiodide Flaming occurs whca bromine trifluoride is dripped onto cooled carbon tetraiodide. Mellor 2, Supp. 1:166 (1956). Cesium Chloride See BROMINE TRIFLUORIDE plus Barium Chloride. Lithium Chloride See BROMINE TRIFLUORIDE plus Barium Chloride. Manganous Iodate See BROMINE TRIFLUORIDE plus Bis- muth Pentoxide. Metals See METALS plus Bromille Trifluoride. Molybder~um See MOLYBDENUM plus Bromine Tri- fluoride. Niobium See NIOBIUM plus Bromine Trifluoride. Niobium Pentoxide See BROMINE TRIFLUORIDE plus Bis- muth Pelttoxide. Organic Matter See BROMINE MONOFLUORIDE plus Water. Platinic Bromide Both platillic bromide and plati,lie chloride are vigorously attacked by bromine trifluoride. MeUor 2, Supp. 1:165 (1956). Platinie Chloride See BROMINE TRIFLUORIDE plus Platini~ Bromide. Platinum and See PLATINUM plus Bromhle Trifluoride and Potassium Fluoride Potassium Fluoride. Potassium Bromide The following salts are rapidly attacked by bromine trifluoride: potassium bromide, potassium chloride, potassium iodide, rhodium tetrabromide, sodium bromide, sodium chloride, sodium iodide. Mellor 2, Supp. 1:164 (1956). Potassium Chloride See BROMINE TRIFLUORIDE plus Po- tassium Bromide. Potassium Iodide See BROMINE TRIFLUORIDE plus Po- tassium Bromide. Rhodium Tetrabromide See BROMINE TRIFLUORIDE plus Po- tassium Bromide. Rubidium Chloride See BROMINE TRIFLUORIDE plus Barium Chloride. Silver Chloride See BROMINE TRIFLUORIDE plus Barium Chloride. 545 :REVISIONS TO NFPA NO. 491M 491M-27 Bromine Trifluoride (cont.) Sodium Bromide See BROMINE TRIFLUORIDE plus Po- tassium Bromide. Sodium Chloride See BROMINE TRIFLUORIDE plus Po- tassium Bromide. Sodium Iodide See BROMINE TRIFLUORIDE plus Po- tassium Bromide. Stannous Chloride Bromine trifluoride and stannous chloride react with flame. MeUor 2, Supp. l: 164 (1956). Tantalum See NIOBIUM plus Bromine Trifluoride. Tantalum Pentoxide See BROMINE TRIFLUORIDE plus Bis- muth Pentoxide. Tin Sec TIN plus Bromine Trifluoride. Titanium See MOLYBDENUM plus Bromine Tri- fluoride. Tungsten See MOLYBDENUM plus Bromine Tri- fluoride. Uranium Oxides The reaction between bromine trifluoride and • oxides of uranium (UO~ U03, and U308) is rapid and quantitative below the boiling point of bromine trifluoride. MeUor 2, Supp. 1:165 (1956). Vanadium See MOLYBDENUM plus Bromine Tri- fluoride. Water See BROMINE MONOFLUORIDE plus Water.

BROMOACETYLENE BrC ! CH Air During tlle preparation of soli d bromoacetylene an explosion occurred when air was drawn into the Volman trap containing the solid bromoacetylene. Although it was well known that gaseous bromoacetylene reacts violently with oxygen at room temperature, the explosion of the solid material at minus 190° C was sur- prising. Chem & Ind. (3) (1972).

BROMOBENZYL TRIFLUORIDE BrC6I-I4CF3 Magnesium See MAGNESIUM plus Bromoben~.yl Tri- fluoride.

BROMODIBORANE BrHB :BH 4 Air This compound burns with a pale green flame in air. Mellor 5- 37 (1946-1947). 546

491M-28 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

BROMOFORM CHBr3 Lithium See LITHIUM plus Bromoform. Sodium-Potassium See SODIUM-POTASSIUM ALLOY plus Alloy Bromoform.

BROMOTRICHLOROMETHANE BrCCI3 Ethylene During the uncatalyzcd addition of bromotrichloromethane to ethylene a violent explosion occurred. BCISC 33:131 (1962). Chem. Abst. 57:9638 (1953).

BUTADIENE- 1, 3 CH2:CHCH:CH2 Chlorine Dioxide See CHLORINE DIOXIDE plus Butadicne. Crotonaldehyde The Diels-Alder reaction between thesc chemicals under pressure is a logical approach to the preparation of a number of cyclic alde- hydes, alcohols, and hydrocarbons. A destruc- tive explosion, including a secondary gas explosion, occurred in carrying out this reaction. K. W. Greenlee, Chem. Eng. News 26:1985 (1948).

•BUTYL ACETATE C4HpOCO.CH3 Potassium Tert.- See ACETONE plus Potassium Tert.-Butoxide. Butoxide

t-BUTYL ALCOHOL (CH3)3COH Hydrogen Peroxide See HYDROGEN PEROXIDE plus t-Butyl Peroxide.

t-BUTYL PERACETATE (CH3)aC-OO-CO.CH3 (self-reactive) t-Butyl peracetate is sensitive to shock and heat. Haz. Chem. Data, p. 77 (1973). Organic Matter Upon contact with t-butyl peracetate combustible organic matter can ignite or give rise to an explosion. Haz. Chem. Data, p. 77 (1973).

t-BUTYL PERBENZOATE (CHa)3 C-O0-CO.CBH5 Organic Matter Organic substances calt ignite or explode upon contact with t-butyl perbenzoate. Haz. Chem. Data p. 79 (1973). 547 REVISIONS TO NFPA NO. 491M 491M-29 t-BUTYL PEROXYACETATE (CH3)~C-OO-CO.CH3 See t-BUTYL PERACETATE.. t-BUTYL PEROXYBENZOATE (CH3)3C-OO-CO.C6H5 Sect-BUTYL PERBENZOATE n-BUTYRALDEHYDE CH3(CH~)2CHO ChlorosulfonicAcid Mixing n-butyraldehyde and chlorosulfonie acid in a closed container causcd the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference.

Nitric Acid Mixing n-butyrMdehyde a,ld 70% nitric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Oleum Mixing n-butyraldehyde and oleum in a closed container caused the temperature and pressure to iacrease. Flynn and Rossow (1970). See Note under complete referencc. Sulfuric Acid Mixing n-butyraldehyde and 96% sulfuric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. CADMIUM Cd Hydrazoic Acid A violent explosioa followed immersion of a cadmium rod in hydrazoic acid after about 30 minutes. Mellor 8, Supp. 2:50 (1967).

CADMIUM AZIDE Cd(N3)~ (self-reactive) This is an extremely hazardous substance, ex- ploding when rubbed with a horn spatula. Mellor 8, Supp. 2:25 (1967).

CADMIUM BROMIDE Cdl3r2 Potassium See POTASSIUM plus Aluminum Bromide.

CADMIUM CHLORIDE CdCI2 Bromine Trifluoridc See BROMINE TRIFLUORIDE plus Barium Chloride. Potassium See POTASSIUM plus Aluminum Bromide. 548 491M-30 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

CADMIUM FLUORIDE CdF2 Potassium See POTASSIUM plus Ammonium Bromide.

CADMIUM IODIDE CdI2 Potassium See POTASSIUM plus Aluminum Bromide.

CADMIUM PERCHLORATE HYDRAZINE Cd(H2NNH~)3(CIO4)2Cd (self-reactive) This is an extremely explosive salt. MeUor 8, Supp. 2:88 (1967).

CADMIUM SULFIDE CdS Iodine Monochloride See IODINE MONOCHLORIDE plus Cad- mium Sulfide.

CALCIUM Ca Chlorine Trifluoride. Chlorine trifluoride combined with calcium or sodium forms a protective crust, but reaction is violent oil heating. Mellor 2, Supp. 1:156 (1956).

CALCIUM CHLORIDE CaC12 Bromine Trifluoride See BROMINE TRIFLUORIDE plus Barium Chloride.

CALCIUM CHLORIDE 2-Furan See 2-FURAN PERCARBOXYLIC. ACID Percarboxylic Acid (self-reactive).

CALCIUM CHLORITE CaOCl Chlorine" See CHLORINE plus Calcium Chlorite.

CALCIUM HYPOCHLORITE CaCI02 Carbon Tetrachloride A severe explosion occurred when a carbon tetrachloride fire extinguisher was used to extinguish a fire in an open container of calcium hypochlorite. NSC Newsletter, Chem. Sec. (May 1972). Mercaptans Calcium hypochlorite and mercaptans will react violently. Barrett (1973). Organic Sulfides Dry calcium hypochlorite when mixed with organic sulfides causes a violent reaction with the possibility of a flash fire. Stephenson (1973). 549 REVISIONS TO NFPA NO. 4911V[ 491M-31

1-Propanethiol An explosion occurred when 10 grams of calcium hypochlorite' was dumped into a beaker containing 5 milliliters of 1-propanethiol. Identical results were obtained with ethanediol and isobutanethiol. R. E. Barrett (1973). Propyl Mercaptan See CALCIUM HYPOCHLORITE plus Mer- captans.

CALCIUM HYPOPHOSPHITE CaPH~O~ Nitric Acid The salt ignites when nitric acid is pourcd onto it. Mellor 8:883 (1946-1947). CALCIUM: OXIDE CaO Boron Trifluoride The reaction of calcium oxide and boron trifluoride forms a fused mass after warming. Mellor 5:123 (1946-1947). Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Alu- mhmm Oxide. Hydrofluoric Acid Liquid hydrofluoric acid and calcium oxide react very violently. Mellor 2, Supp. 1:129 (1956). Phosphorus Pentoxide Calcium oxide or sodium hydroxide reacts with phosphorus pentoxide extremely violently when initiated by local heating. Mellor 8, Supp. 3:406 (1971).

CALCIUM PERCHROMATE Ca3(CrO03)2 (self-reactive) Calcium perchromate is a buff-colored powder that explodes at 100 ° C. Mellor 11:359 (1946-1947). CALCIUM PHOSPHIDE Ca3P2 Chlorine See CHLORINE plus Calcium Phosphide. Hydrochloric Acid Calcium phosphide and hydrochloric acid undergo a very energetic reaction. Mellor 8:841 (1946-1947). Oxygen See SULFUR plus Calcium Phosphide. Sulfur See SULFUR plus Calcium Phosphide. Water Mellor 8: 841 (1946-1947).

CARBIDES Lithium See LITHIUM plus Carbides. Oxidizing Agents Mixtures of carbides and oxidizing agents are explosive. Mellor 5:848 (1946-1947). 550 491M-32 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

CARBOHYDRATES Boron Triiodide See BORON TRIIODII)E plus Ethe,'s.

CARBON C 2-Furan Percarboxylic See 2-FURAN PERCARBOXYL1C ACID Acid (self-reactive). Mercurous Nitrate At high temperature, a mixture of mercurous nitrate and carbott decomposes exl)losively. Mellor 4:987 (1946-1947). Nitric Acid Pulverized carbon reacts violently with nitric acid. Pascal 10:504 (1931-1934). Potassium and Air See POTASSIUM plus Carbon and Air.

CARBON DIOXIDE CO~ Lithium See LITHIUM plus Water. Potassium See POTASSIUM plus Carbon Dioxide.

CARBON DISULFIDE CS~ Aluminum See ALUMINUM plus Carbon Disulfide. Ethylene Diamine Mixing carbon disulfide and ethylene diamine in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete rcfcrence. Ethyleneimine Mixing carl)on disulfide ,'rod cthyleneimiue in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference.

CARBON MONOXIDE CO Bromine Trifluoride See BROMINE TRIFLUORIDE plus Carbon Monoxide. Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Am- monia. Iodine Heptafluoridc See IODINE HEPTAFLUORIDE plus Carbon Monoxide. Lithium and Water See LITHIUM plus Carbon Monoxide attd Water, Oxygen Difluoride See HYDROGEN plus Oxygen Difluoride. Potassiuln and Oxygen See POTASSIUM plus Carbon Monoxkle and Oxygen. Sodium and Ammonia See SODIUM plus Carbon Monoxide and Ammonia. 551 REVISIONS TO NFPA NO. 491M 491M-33

CARBON TETRABROMIDE CBr4 Lithium See LITHIUM plus Bromoform.

CARBON TERACHLORIDE CC14 Bromine Trifluoride See BROMINE TRIFLUORII)E plus C~rbon Tetrachloride. Calcium Hypochlorite See CALCIUM HYPOCHLORITE plus Car- bon Tetrachloride. Diborane A violent explosion occurred when carbon tetrachloride was uscd on a borane fire. Fawcett (1973). Dimcthyl Formamide See DIMETHYL FORMAMIDE plus Carbon Tetrachloride. Potassium See POTASSIUM plus Boron Tribromide. Potassium Tert.- See ACETONE plus Potassium Tert.-

Butoxide Butoxide. y Silver Perchlorate and See SILVER PERCHLORATE plus Carbon Hydrochloric Acid Tetrachloride and Hydrochloric Acid. Sodium See SODIUM plus Cobaltous Bromide.

CARBON TETRAIODIDE CI4 Bromine Trifluoridc Sec BROMINE TRIFLUORIDE plus Carbon Tetra iodide.

CELLULOSE (C6Hl2Os)x Bromine Pentafluoride See BROMINE PENTAFLUORIDE plus Acetic Acid. Fluorine See FLUORINE plus Cellulose. Hydrogen Peroxide See HYDROGEN PEROXIDE plus Cellulose.

CERIUM Ce Phosphorus Ceritun or lanthamml and phosphorus react violently at 400 ° - 500° C. MeUor 8, Supp. 3: 347, 252 (1971).

CEROUS PHOSPHIDE CeP Water The reaction of eerous phosphide, lanthanum phosphide, or neodymium phosphide and water liber~tes spontaneously flammable phosphine. Mellor 8, Supp. 3: 347, 342, 348 (1971). CESIUM Cs Chlorine Chlorine vapors and cesium, lithium, or rubidium react with luminous flame. Mellor 2, Supp. 1:380 (1956). Phosphorus See PHOSPHORUS plus Cesium. 552 491M-34 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

CESIUM AZIDE CsN~ (self-reactive) Cesium azidc decomposes at 326 ° C. Mellor 8, Supp. 2:43 (1967).

CESIUM CARBIDE CS2C2 Iodine See IODINE plus Cesium Carbide.

CESIUM CHLORIDE CsC1 Bromine Trifluoridc See BROMINE TRIFLUORIDE plus Barium Chloride. CHARCOAL C Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Char- coal. Potassium See POTASSIUM plus Charcoal.

CHLORATES Phosphorus See PHOSPHORUS plus Chlorates. Selenium See SELENIUM plus Chlorates. Sulfuric Acid The reaction of chlorates and sulfuric acid (to form chlorine dioxide) may cause explosions. Mellor 2, Supp. l: 521 (1956).

CHLORIC ACID HCI03 (self-reactive) Concentrations of chloric acid above 40% decompose. Mellor 2, Supp. l: 576 (1956). Ammonia See ANTIMONY plus Chloric Acid. Antimony See ANTIMONY plus Chloric Acid. Bismuth See ANTIMONY plus Chloric Acid. Organic Matter See ANTIMONY plus Chloric Acid.

CHLORINE C12 Alkylphosphines Unless precautions are taken, the reaction of chlorine with alkylphosphines or dialkylphosphines is a vigorous decomposing reaction. MeUor 8, Supp. 3:900 (1971). Ammonia MeUor 8, Supp. 2:330 (1964). Arsine Mellor 2, Supp. 1:379 (1956). Barium Phosphide The phosphide ignites in chlorine at 90 ° C. MeUor 8, Supp. 3:842 (1971). Bromine Pentafluoride Mixture of chlorine and bromine pentafluoride explodes on heating. Mellor 2, Supp. 1:173 (1956). 553 REVISIONS TO NFPA NO. 4915/[ 491M-35

Calcium Chlorite The reaction of chlorine and a clilute solution of calcium chlorite evolves explosive chlorine dioxide. Mellor 2, Supp. 1:382 (1956). See also CHLORINE DIOXIDE (self-reactive). Calcium Phosphide Mixtures of chlorine and calcium phosphide react readily at about 100 ° C. Mellor 8:841 (1946-1947). Cesium See CESIUM plus Chlorine. Dialkylphosphines See CHLORINE plus Alkylphosphines. Dibutyl Phthalate See CHLORINE plus Polypropylene. Drawing Wax See CHLORINE plus Polypropylene Ethylene The reaction of chlorine and ethylene is explosive at room temperature over yellow mercuric oxide, mercurous oxide, or silver oxkle. MeUor 2, Supp. 1:380 (1956). Fluorine Reaction of chlorine and fluorine is accompanied by flames. In the presence of a spark, a violent explosion occurs. Mellor 2, Supp. 1:58 (1956). Glycerol Sec CHLORINE plus Polypropylene. Hydrocarbons During treatment of naphtha with an aqueous caustic-hypochlorite solution to remove ob- jectionable odors, an explosion,occurred in the mixer. Just before the detonation, liquid chlorine had been added to strengthen the hypochlorite solution. The explosion is attributed to the highly exothermic liquid phase reaction of chlorine and saturated hydrocarbons. Chem. Eng. Progs. 58(6): 71-74 (1962). Mellor 2, Supp. 1:380 (1956). Hydrogen Peroxide Red luminescence occurs (luring reaction of and Potassium chlorine and hydrogen peroxide in strong Hydroxide potassium hydroxide solution. Mellor 2, Supp. 1:378 (1956). Iodine The reaction of liquid chlorine and iodine is violent. Mellor 2, Supp. 1:378 (1956). Linseed Oil See CHLORINE plus Polypropylene. Lithium See CESIUM plus Chlorine. Mercuric Oxide Chlorhm reacts rapidly at room temperature with both mercuric oxide and silver oxide. Mellor 2, Supp. 1:381 (1956). Mercury See MERCURY plus Chlorine. 554

401M-36 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES Chlorine (cont.) Methane The reaction of chlorine and methane is e.x- plosive at room temperature over yellow mercuric oxide. Mellor 2, Supp. 1:380 (1956). Niobium See NIOBIUM plus Chlorine. Oxygen Difluoride The reaction between chlorine and oxygen difluoride produces a reddish-brown solid that explodes at about minus 10 ° C. Mellor 2, Supp. 1:182 (1956). A mixture of chlorine and oxygen fuoride explodes on gentle warming. Puffs or more violent explosious occur if mixturc is in copper tubing at 300 ° C. Mellor 2, Supp. 1:192 (1956). Oxygen Difluoride and See CHLORINE plus Oxygen Difluoride. Copper Phosphorus and See PHOSPHORUS plus Chlorine and Hep- Heptane tane. Phosphorus Isocyanate The reaction of phosphorus isocyanate and chlorine is vigorous, forming a yellow oil. Mellor 8, Supp. 3:585 (1971). Polychlorinated Liquid chlorine reacts exothermically with Biphenyl polychlorinated biphenyl heat transfer liquid. W. A. Statesir, Chem. Eng. Progs. 69 (4): 52-54 (1973). Polydimethylsiloxane See CHLORINE plus Polypropylene. Polypropylenc Liquid chlorine reacts explosively with polypropylene, drawing wax, polydimethyl-siloxane, dibutyl phthalate, glycerol, and linseed oil. , W. A. Statesir, Chem. Eng. Progs. 69 (4): 52-54 (1973). Rubidium See CESIUM plus Chlorine. Silver0xide See CHLORINE plus Mercuric Oxide. Sodium Carbide This carbide burns in chlorine gas. Mellor 5:848 (1946-1947). Stannous Fluoride The reaction of chlorine a:ld stammus fuoride occurs with flaming. Mellor 2, Supp. 1:382 (1956). Strontium Phosphide Mixtures of these materials ignite at about 30 ° C. Mellor 8:841 (1946-1947). Tin See TIN plus Chlorine.

CHLORINE AZIDE N3CI (self-reactive) Chlorine azide is spontaneously explosive. MeUor 8:336 (1946-1947). Mellor 8, Supp. 2:50 (1967). 555 REVISIONS TO NFPA NO. 491M 491M-37

Butadiene-1, 3 Chlorine dioxide mixed with butadiene, ethane, ethylene, methane or propane always explodes spontaneously. J.K.K. Ip and P. Gray, Comb. & Flame 19: 117-129 (1972). Ethane See CHLORINE DIOXIDE plus Butadiene. Ethylene See CHLORINE DIOXIDE plus Butadie'ne. Methane See CHLORINE DIOXIDE plus Butadiene. Propane See CHLORINE DIOXIDE plus Butadiene.

CHLORINE FLUOROXIDE OCIF (self-reactive) Chlorine fluoroxide is explosively unstable. Mellor 2, Supp. 1:182 (1956).

CHLORINE MONOFLUORIDE CIF Organic Matter See BROMINE MONOFLUORIDE plus Water. Water See BROMINE MONOFLUORIDE plus Water.

CHLORINE MONOXIDE C120 (self-reactive) Chlorine monoxide is highly explosive if heated rapidly or overheated locally. Mellor 2, Supp. 1:517 (1956). Organic Matter Chlorine monoxide often explodes violently in contact with organic compounds. Mellor 2, Supp. 1:520 (1956).

CHLORINE TRIFLUORIDE C1Fa Acetic Acid The reaction between chlorine trifluoride and acetic acid is very violent, sometimes explosive. Mellor 2, Supp. 1:155 (1956). Aluminum See ALUMINUM plus Chlorine Trifluoride. Almninum Oxide Chlorine trifluoride reacts violently, producing fame, with aluminum oxide, calcium oxide, chromium oxide, lead dioxide, magnesium oxide, manganese dioxide, molybdenum trioxide, tantalum pentoxide, tungsten trioxide, or vanadium pentoxide. Mellor 2, Supp. 1:157 (1956). See also CHLORINE TRIFLUORIDE plus Elements. Ammonia Chlorine trifluoride causes an explosive reaction with ammonia, carbon monoxide, hydrogen sulfide, sulfur dioxide, or hydrogen. Mellor 2, Supp. 1:157 (1956). 556 491M-38 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

Antimony See ANTIMONY plus Chloril~e Trifluoride. Arsenic See ANTIMONY plus Chlorine Trifluoride. Arsenic Trioxide Chlorine trifluoride produces a violent reaction without flame in presence of arsenic trioxide, bismuth trioxide, lanthanum oxide, phosphorus pentoxide, or sta~mic oxide. Mellor 2, Supp. 1:157 (1956). See also CHLORINE TRIFLUORIDE plus Elements. Benzene The reaction between chlorine trifluoride and benzene is very violent, sometimes explosive. Mellor 2, Supp. 1:155 (1956). Bismuth Trioxide See CHLORINE TRIFLUORIDE plus Ar- senic Trioxide. Calcium See CALCIUM plus Chlorine Trifiuoride. Calcium Oxide See CHLORINE TRIFLUORIDE plus Alu- minum Oxide. Carbon Monoxide See CHLORINE TRIFLUORIDE plus Am- monia. Charcoal Chlorine trifluoride causes charcoal, glass wool (rapidly etched with traces of moisture), or graphite to burst into fame. Mellor 2, Supp. 1:157 (1956). Chromic Anhydride Chlorine trifluoride and chromic anhydride react violently with evolution of brown fumes. MeUor 2, Supp. 1:157 (1956). Mellor 11:230 (1946-1947). Chromium Oxide See also CHLORINE TRIFLUORIDE plus Aluminum Oxide. Copper" See ALUMINUM plus Chlorine Trifluoride. Diethyl Ether The reaction between chlorine and diethyi ether is very violent, sometimes explosive. Mellor 2, Supp. 1:155 (1956). Glass See also CHLORINE TRIFLUORIDE plus Charcoal. Graphite See CHLORINE TRIFLUORIDE plus Char- coal. Hydrogen See CHLORINE TRIFLUORIDE plus Am- monia. Hydrogen Sulfide See CHLORINE TRIFLUORIDE plus Am- monia. Iodine See CHLORINE TRIFLUORIDE plus Mer- curic Iodide. Lanthanum Oxide See CHLORINE TRIFLUORIDE plus Ar- senic Trioxide. 557 REVISIONS TO NFPA NO. 491M 491M-39 Chlorine Trifluoride (cont.) Lead See ALUMINUM plus Chlorine Trifluoride. Lead Dioxide See CHLORINE TRIFLUORIDE plus Alu- minum Oxide. Magnesium See ALUMINUM plus Chlorine Trifluoride. Magnesium Oxide See CHLORINE TRIFLUORIDE plus Alu- minum Oxide. Manganese Dioxide See also CHLORINE TRIFLUORIDE plus Aluminum Oxide. Mercuric Iodide Combination of chlorine trifluoride and mercuric iodide, tungsten carbide, or iodine results in a reaction with flame. Mellor 2, Supp. 1:157 (1956). Molybdenum Trioxide See also CHLORINE TRIFLUORIDE plus Aluminum Oxide. Nitric Acid (Fuming) Combination of chlorine trifluoride and fuming nitric acid, potassium carbonate, potassium iodide, silver nitrate, 10°/o sodium hydroxide or sulfuric acid results in a violent reaction. MeUor 2, Supp. 1:157 (1956). Nitroaromatic Com- See NITROAROMATIC COMPOUNDS plus pounds Chlorine Trifluoride. Organic Matter Mellor 2, Supp. 1:155 (1956). Organic Matter See also BROMINE MONOFLUORIDE plus Water. Osmium See ANTIMONY plus Chlorine Trifluoride. Phosphorus See ANTIMONY plus Chlorine Trifluoride. Phosphorus Pentoxide See CHLORINE TRIFLUORIDE plus Ar- senic Trioxide. •Potassium See ANTIMONY plus Chlorine Trifluoridc. Potassium Carbonate See CHLORINE TRIFLUORIDE plus Nitric Acid. Potassium Iodide See CHLORINE TRIFLUORIDE plus Nitric Acid. Rhodium See ANTIMONY plus Chlorine Trifluoride. Rubber When chlorine trifluoride is in contact With rubber a violent reaction occurs. Mellor 2, Supp.. 1:156 (1956). Selenium See ANTIMONY plus Chlorine Trifluoride. Silicon Scc ANTIMONY plus Chlorine Trifluoride. Silver See ALUMINUM plus Chlorine Trifluoride. Silver Nitrate See CHLORINE TRIFLUORIDE plus Nitric Acid. Sodium See CALCIUM plus Chlorine Trifluoride. Sodium Hydroxide See CHLORINE TRIFLUORIDE plus Nitric Acid. 558 491M-40 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES Chlorine Trifluoride (cont.) Stannic Oxide See CHLORINE TRIFLUORIDE plus Ar- senic Trioxide. Sulfur See ANTIMONY plus Chlorine Trifluoride. Sulfur Dioxide See CHLORINE TRIFLUORIDE plus Am- monia. Sulfuric Acid See CHLORINE TRIFLUORIDE plus Nitric Acid. Tantalum Pentoxide See CHLORINE TRIFLUORIDE plus Alu- minum Oxide. Tellurium See ANTIMONY plus Chlorine Trifluoride. Tin See ALUMINUM plus Chlorine Trifltmride. Tungsten See ANTIMONY plus Chlorine Trifluoride. Tungsten Carbide See CHLORINE TRIFLUORIDE plus Mer- curic Iodide. Tungsten Trioxide See also CHLORINE TRIFLUORIDE plus Aluminum Oxide. Vanadium Pentoxide See CHLORINE TRIFLUORIDE plus Alu- minum Oxide. Water See also BROMINE MONOFLUORIDE plus Water. Zinc See ALUMINUM plus Chlorine Trifluoride.

CHLORINE TRIOXIDE C10a (self-reactive) Explosions occurred during preparation of chlorine trioxide. Mellor 2, Supp. 1:540 (1956). Ethyl Alcohol No really safe conditions exist under which ethyl alcohol and chlorine oxides can be handled. Mellor 2, Supp. 1:540 (1956). Organic Matter Chlorine trioxide reacts violently, even explosively, with stopcock grease, wood, most forms of organic mattcr. MeUor 2, Supp. 1:540 (1956). Water Chlorine trioxide reacts vigorously and may explode with water. Mellor 2, Supp. 1:540 (1956).

CHLOROACETALDEHYDE OXIME C1CH2CH:NOH (self-reactive) Separation of chloroacetaldehydc oxime from ether by distillation must not be carried out too far or a violent explosion will occur. MCA Guide for Safety, Appendix 3 (1972). 559 REVISIONS TO NFPA NO. 491M 491M-41

CHLOROACETONE CH2C1C(O)CHa (self-reactive) Chloroacetone had turned black during storage for two years on a shelf in dull diffused light. A few days after the bottle of chloroacetone was moved, it exploded. The chloroacetone had polymerized to a black rubber-like substance. Ind. & Eng. Chem. News9:184 (1931).

CHLOROBENZENE CsHsCI Silver Perchlorate See SILVER PERCHLORATE plus Acetic Acid.

CHLOROBENZOTRIAZOLE- 5 NHN :N-C6H3C1 (self-reactive) Chlorobenzotriazole -5 spontaneously burst into flame while being packaged. H. S. Hopps, Chem. Eng. News 49 (30): 3 (1971). J. Chem. Eng. Data 17:108 and 109 (1972).

3-CHLOROCYCLOPENTENE (-CH :CHCHC1CH~CH2-) (self-reactive) Thirty-five grams of 3-chlorocyclopentene exploded one day after it was made. Merck Safety Report (April 1962).

CHLORODIBORANE C1HB :BH4 Air This compound is spontaneously flammable in air. MeUor 5:37 (1946-1947).

CHLOROFORM ClaCH Potassium Tert.- See ACETONE plus Potassium Tert.- But- Butoxide oxide.

CHLOROHYDRIN C1CH~CH~OH Sodium Hydroxide See SODIUM HYDROXIDE plus Chloro- hydrin. p-CHLOROPHENYL ISocYANATE CIC6H4NCO (self-reactive) A violent explosion occurred in a laboratory during vacuum distillation of p-chlorophenyl isocyanate that had been prepared by the Curtius reaction of p-chlorobenzoylazide. Chem. & Ind. 38:1625 (1965). 560 491M-42 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

CHLOROPICRIN C13CNO~ (self-reactive) Tank car volumes of this material may detonate under certain conditions. There is a critical volume above which sufficient shock may cause detonation. Chem. Eng. News 50 (38):13 (1972).

CHLOROSULFONIC ACID C1S020H Acetic Acid See ACETIC ACID plus Chlorosulfonic Acid. Acetic Anhydride See ACETIC ANHYDRIDE plus Chloro- sulfonic Acid. Acetonitrile See ACETONITRILE plus Chlorosulfonic Acid. Acrolein See ACROLEIN plus Chlorosulfonic Acid. Acrylic Acid See ACRYLIC ACID plus Chlorosulfonic Acid. Acrylonitrilc See ACRYLONITRILE plus Chlorosulfonic Acid. Allyl Alcohol See ALLYL ALCOHOL plus Chlorosulfonic Acid. Allyl Chloride See ALLYL CHLORIDE plus Chlorosulfonic Acid. 2-Aminoethanol See 2-AMINOETHANOL plus Chlorosulfonic Acid. Ammonium Hydroxide Mixing chlorosulfonic acid ~,~d 28% ammonia in a closed container c~used the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Aniline See ANILINE plus Chlorosulfonic Acid. n-Butyraldchyde See n-Butyraldehyde plus Chlorosulfonic Acid. Creosote Oil Mixing chlorosulfonic acid and creosote oil in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Cresol See CRESOL plus Chlorosulfonic Acid. Cumene See CUMENE plus Chlorosulfonic Acid. Dichloroethyl Ether See DICHLOROETHYL ETHER plus Chloro- sulfonic Acid. .Diethylene Glycol See DIETHYLENE GLYCOL MONO- Monomethyl Ether METHYL ETHER plum Chlorosulfo~fic Acid. Diisobutylene See DIISOBUTYLENE plus Chlorosulfolfic Acid. Diisopropyl See DIISOPROPYL ETHER plus Chloro- sulfonic Acid. 561 REVISIONS TO NFPA NO. 491M 491M--43

Epichlorohydrin See EPICHLOROHYDRIN plus Chloro- sulfonic Acid. Ethyl Acetate See ETHYL ACETATE plus Chlorosulfonic Acid. Ethyl Acrylate See ETHYL ACRYLATE plus Chlorosulfonic Acid. Ethylene Chlorohydrin See ETHYLENE CHLOROHYDRIN plus Chlorosulfonic Acid. Ethylene Cyanohydrin See ETHYLENE CYANOHYDR1N plus Chlorosulfoaic Acid. Ethylene Diamine See ETHYLENE DIAMINE plus Chloro- sulfonie Acid. Ethylene Glycol See ETHYLENE GLYCOL plus Chloro- sulfonic Acid. Ethylene Glycol See ETHYLENE GLYCOL MONOETHYL Monoethyl Ether ETHER ACETATE plus Chlorosulfonic Acid. Acetate Ethyleneimine See ETHYLENEIMINE plus Chlorosulfonic Acid. Glyoxal See GLYOXAL plus Chlorosulfonic acid. Hydrochloric Acid Mixing chlorosulfonic acid and 36% hydrochloric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Hydrofluoric Acid Mixing ehlorosulfouie acid and 48.7% hydrofluoric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Hydrogen Peroxide Permonosulfonic acid was being prepared by reacting chlorosulfonic acid and 90% hydrogen peroxide. A sample was stored overnight at 0 ° C, then removed to a test tube rack. In ten minutes it exploded. Chem. Eng. News 33:3336 (1955). See also PERMONOSULFURIC ACID plus Acetone. Isoprene See ISOPRENE plus Chlorosulfonic Acid. Mesityl Oxide See MESITYL OXIDE plus Chlorosulfouic acid. Methyl Ethyl Ketone See METHYL ETHYL KETONE plus Chlorosulfonic Acid. 562 491M-44 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES Chlorosulfonic Acid (cont.) Nitric Acid Mixing chlorosulfonic acid and 70% nitric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note uIlder complete reference. 2- Nitropropane Mixing chlorosulfolfic acid and 2-nitropropane in a closed container caused the temperature pressure to increase. Flynn and Rossow (1970). See Note ul~der complete reference. Propiolactone (BETA-) See PROPIOLACTONE (BETA-) plus Chloro- sulfonic Acid. Propylene Oxide See PROPYLENE OXIDE plus Chlorosul- fonic Acid. Pyridine See PYRIDINE plus Chlorosulfonic Acid. Sodium Hydroxide See SODIUM HYDROXIDE plus Chloro- sulfonic Acid. Styrene Monomer See STYRENE MONOMER plus Chloro- sulfottic Acid. Sulfolane See SULFOLANE plus Chlorosulfonic Acid. Sulfuric Acid Mixing chlorosulfonic acid and 96% sulfuric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Vinyl Acetate See VINYL ACETATE plus Chlorosulfonic Acid. Vinylidene Chloride See VINYLIDENE cHLORIDE plus Chloro- sulfonic Acid.

CHLOROTRIFLUOROETHYLENE CIFC:CF: Bromine and Oxygen Addition of bromine to a mixture of chlorotrifluoroethylene and oxygell causes an explosion. One of the products of the reaction is chlorotrifluoroethylene peroxide, which explodes when heated. R. N. Haszcldine and F. Nyman, J. Chem. Soc. 1959:1084-1090 (1959).

CHLOROTRIFLUOROETHYLENE PEROXIDE CF2C1COF (self-reactive) Chlorotrifluoroethylelm peroxide explodes when heated. R. N. Haszeldine and F. Nyman, J. Chem. Soc. 1959: 1084,-90 (1959). 563 REVISIONS TO NFPA NO. 491M 491M-45

CHROMIC ANHYDRIDE Cr03 Aluminum See ALUMINUM plus Chromic Anhydride. Ammonia Mellor 11:233 (1946-1947). Benzene Benzene ignites in contact with powdered chromic anhydride. Mellor ll: 235 (1946-1947). Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Chromic Anhydride. Diethyl Ether These compounds react violently at room temperature. Mellor 11:235 (1946-1947). Organic Matter A container of 50 kilograms of chromic am hydride exploded when laid on the ground. The container may have been contaminated with an oxidizable substance. Chem. Abst. 31:4010 (1937). Sodium Amide See SODIUM AMIDE plus Chromic Anhy- dride.

CHROMIC OXIDE Cr, Oa Lithium See LITHIUM plus Chromic Oxide. Oxygen Difluoride See OXYGEN DIFLUORIDE plus Aluminum Chloride. CHROMIUM Or Lithium See LITHIUM plus Vanadium.

CHROMIUM-AMMINE NITRATES (self-reactive) Chromium-ammine nitrates may be impact- sensitive: Cr(NHa)~NO~(NOa)2 detonates when heated. Mellor 11:477 (1946-1947).

CHROMIUM-AMMINE PERCHLORATES (self-reactive) Chromium-ammine perchlorates may be impact-sensitive. Mellor 11:477 (1946-1947).

CHROMIUM TETRACHLORIDE CrCI, Potassium See POTASSIUM plus Aluminum Bromide. Sodium See SODIUM plus Chromium Tetrachloride.

CHROMIUM TRIAMMINOTETROXIDE Cr (NH3)sO, (self-reactive) Chromium triamminotetroxide detonates and becomes incandescent when heated. Mellor 11 : 358 (1946-1947). 564 491M-46 REPORT OF COMMITTEE ON CHEMICALSAND EXPLOSIVES

CHROMIUM TRIFLUORIDE CrF3 Potassium See POTASSIUM plus Ammonium Bromide.

CHROMYL CHLORIDE CrOsCI2 Fluorine See FLUORINE plus Chromyl Chloride. Sodium Azide See SODIUM AZIDE plus Chromyl Chloride.

COBALT ALLOYS See LITHIUM plus Cobalt Alloys.

COBALTIC FLUORIDE CoF3 Silicon See SILICON plus Colbatic Fluoride.

COBALT NITRIDE CoN Air MeUor 8, Supp. 1:238 (1964).

COBALTOUS BROMIDE CoBr2 Potassium See POTASSIUM plus Boron Tribromide. Sodium See SODIUM plus Cobaltous Bromide.

COBALTOUS CHLORIDE CoCI2

COBALTOUS HYPOPHOSPHITE C0(PH202)2 (self-reactive) Cobaltous hypophosphite liberates spontaneously flammable phosphine above 150° C. MeUor 8:889 (1946-1947). COPPER Cu Ammonium Nitrate MeUor 8, Supp. 1:546 (1964). Chlorine Copper reacts vigorously with chlorine at around 320 ° C. MeUor 2, Supp. 1:380 (1956). Chlorine and Oxygen See CHLORINE plus Oxygen Difluoride. Difluoride Chlorine Trifluoride See ALUMINUM plus Chlorine Trifluoride. Hydrazoic Acid " Explosions resulted from corrosion of brass parts of a vacuum gage and water jet vacuum pump on prolonged contact with hydrozoic acid vapors. Chem. & Ind. 10, p. 444 (1973). Phosphorus The reacting mass formed by the mixture of phosphorus and copper, iron, nickel, or platinum can become incandescent when heated. Mellor 8, Supp. 3:228 (1971). Sodium Azide See SODIUM AZIDE plus Copper. 565 REVISIONS TO NFPA NO. 491M 491M-47

COPPER AZIDE Cu (N3)2 (self-reactive) See SODIUM AZIDE plus Copper.

COPPER OXYCHLORIDE CuzOCI2 Potassium See POTASSIUM plus Boric Acid.

COPPER SALTS Hydrazine Copper salts promote the decomposition of hydrazine. Chem. Eng. News 48 (48): 97 (Nov. 16, 1970). See also CUPRIC OXIDE plus Hydrazine. Nitromethane Nitromethane and salts of copper, silver, gold or mercury spontaneously form explosive materials. Chem. Eng. News 49 (23):.6 (1971).

CREOSOTE OIL CH3CsH40H Chlorosulfonic Acid See CREOSOTE OIL plus Chlorosulfonic Acid.

CRESOL CH3C6H4OH Chlorosulfonic Acid Mixing cresol and chlorosulfonic acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Nitric Acid Mixing cresol and 70% nitric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Oleum Mixing cresol and oleum in a closed container caused the temperature and pressure to in- creasc. Flynn and Rossow (1970). See Note under complete reference.

CROTONALDEHYDE CH3CH :CHCHO Butadiene-1, 3 See BUTADIENE-1,3 plus Crotonaldehyde.

CUMENE C6H~CH(CH3)2 Chlorosulfonic Acid Mixing Cumene and chlorosulfoaic acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. 566 491M-48 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

Nitric Acid Mixing cumene and 70% nitric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Oleum Mixing cumene and oleum in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under com- .plete reference.

CUMENE HYDROPEROXIDE C6HsC(CH3)2OOH (self-reactive) At concentrations of 91 and 95%,-cumene hydroperoxide decomposed violently at about 150 ° C. A. Le Roux, Mem. Poudres 37:49-58 (1955).

CUPRIC AZIDE Cu(N,), (self-reactive) Spontaneous explosions have been observed with this compound. Mellor 8, Supp. 2:50 (1967).

CUPRIC BROMIDE CuBr2 Potassium See POTASSIUM plus Aluminum Bromide.

CUPRIC.:CHLORATE HYDRAZINATE Cu(H2NNH2)~CI03 (self-reactive) This is an extremely explosive salt and will detonate on drying. MeUor 8, Supp. 2:88 (1967). MeUor 2, Supp. 1:592 (1956).

CUPRIC CHLORIDE CuC12 Potassium See POTASSIUM plus Aluminum Bromide. Sodium See SODIUM plus Aluminum Bromide.

CUPRIC' CHLORITE Cu(ClO~)2 (self-reactive) Cupric chlorite explodes violently on percussion. In the dry state it decomposes within 12 days. Mellor 2, Supp. l: 574 (1956). 567 REVISIONS TO NFPA NO. 491M 491M-49

CUPRIC HYPOPHOSPHITE Cu(PH~Os)2 (self-reactive) Cupric hypophosphite forms impact-sensitive ammunition-priming mixtures. Mellor 8, Supp. 3:623 (1971). Cupric hypophosphite explodes suddenly at about 90 ° C. Mallor 8:883 (1946-1947).

CUPRIC NITRATE Cu(NO3)z Potassium A finely ground mixture of potassium ferro- Ferrocyanide cyanide and cupric nitrate when dried at 220 ° C exploded within a few minutes. Chem. Abst. 77: 13431f (1972).

CUPRIC OXIDE Cu0 Boron See BORON plus Cupric Oxide.

CUPRIC SALTS Sodium Hypobromite See SODIUM HYPOBROMITE plus Cupric Salts.

CUPRIC SULFIDE CuS Hydrogen Peroxide See ANTIMONY TRISULFIDE plus Hydro- gen Peroxide.

CUPROUS AZIDE CuNa (self-reactive) Cuprous azide decomposes at 205°C. It is explosively unstable. MeUor 8, Supp. 2:43 (1967).

CUPROUS BROMIDE CuBr. Potassium See POTASSIUM plus Aluminum Bromide.

CUPROUS CHLORIDE CuCl Potassium See POTASSIUM plus Aluminum Bromide.

CUPROUS IODIDE CuI" Potassium See POTASSIUM plus Aluminum Bromide.

CUPROUS NITRIDE Cu3N Nitric Acid See CUPROUS NITRIDE plus Sulfuric Acid. Sulfuric Acid The reaction of cuprous nitride and sulfuric or nitric acid is violent. Mellor 8, Supp. 1:154 (1964). 568 491M-50 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

CYANOGEN AZIDE NCNNN (self-reactive) Cyanogen azide explodes when shocked mech- anically or thermally. Chem. Eng. News 43 (52): 29, 30 (Dec. 27, 1965).

CYANURIC ACID NHCO.NHCO.NHCO Ethyl Alcohol See CYANURIC ACID plus Water.

CYANURIC CHLORIDE N:CCIN:CC1N:CCI Water Cyanuric chloride acts autocatalytically with water at a temperature of about 30 ° C to produce cyanuric acid, hydrochloric acid and heat. An explosion occurred during an industrial process in which cyanuric chloride and water were mixed. The refrigeration had been turned off. Pressure build-up in the reactor blew gaskets allowing flamniable vapors to fill the building. The explosion occurred when the vapors were ignited. MCA Case History 1869 (1972).

CYCLOHEXANE C6H12 Nitrogen Dioxide Through an error, liquid nitrogen dioxide in- stead of gaseous was fed into a nitration column containing hot cyclohexane. An explosion resulted. MCA Case History 128 (1962).

CYCLOHEXANOL C6HnOH Nitric Acid See NITRIC ACID plus Cyclohexanol.

DIACETYL PEROXIDE (CH3C0)202 (self-reactive) Pure diacetyl peroxide is a severe explosion hazard. Cond. Chem. Dict. 10: (1971). See also HYDROGEN PEROXIDE plus Acetic Anhydride.

DIALKYLPHOSPHINES Chlorine See CHLORINE plus Alkylphosphines. 569 REVISIONS TO NFPA NO. 491M 491M-51

DIALLYL METHYL CARBINOL (CHo.:CHCHr)2C(OH)CH3 Ozone and Acetic Acid During the preparation of ~-hydroxy-B- methyl glutaric acid using 75 grams of diallyl methyl carbiaol the material had been ozordzed and allowed to stand overnight. Glacial acetic acid had been added and the mixture was being concentrated under vacuum in a desiccator. After 11/'~hours the mixture exploded. Previous preparations using 12.6 grams were successful. Chem. Eng. News. 51 (6): 29 (Feb. 5, 1973). DIALLYL PHOSPHITE (C3HsO)~POH (self-reactive) Diallyl phosphite is made from allyl alcohol and phosphorus trichloride. When the product is distilled in vacuo ina carbon dioxide stream, explosions usually occur after about two-thirds is distilled. Zh. Obshch. Khim. 21:658-62 (1951). DIAZOCYCLOPENTADIENE NN :CCH2CH:CHCH: I. .I (self-reactive) Diazocyclopentadiene should be handled cau. tiously since during one preparation a violent explosion took place after distillation. F. Ranairez and S. Levy, J. Org. Chem. 23: 2036-7 (1958). DIAZOMALONIC ACID (HOCO.)2C:NN (self-reactive) Six grams of impure diazomalonic acid was being distilled under 3 millimeters pressure in a 50 milliliter fask. After three minutes of heating, during which no product was obtained, the flask exploded. NSC Newsletter, Campus Safety 3 (1973). DIBORANE H2B :BH4 Carbon Tetrachloride See CARBON TETRACHLORII)E plus Di- borane. Nitric Acid See NITRIC ACID plus Diborane. Phosphorus Trifluoride See PHOSPHORUS TRIFLUORIDE plus Diborane. 2, 6-DIBROMO-p-BENZOQUINONE-4-CHLORIMINE 0 :C6H2Br :NCI (self-reactive) While thin layer chromatograms ~;ere .being dried with a hot-air dryer, a 25-gram bottle of 2, 6-dibromo-p-benzoquinone-4-chlorimine, one to two feet away, exploded. Chem. & Ind. 37:1551 (1967). 570 491M-52 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

DIBUTYL PHTHALATE (C4HgCCO.)2CsH4 Chlorine See CHLORINE plus Polypropyleue.

DIBUTYL SULFOXIDE (C4H9)2SO Perchloric Acid See PERCHLORIC ACID plus Dibutyl S'ul- foxide.

DICHLORINE HEPTOXIDE C1207 (self-reactive) Dichloritm heptoxide explodes violently under a blow or when heated rapidly. MeUor 2, Supp. 1:542 (1956).

1, 6-DICHLORO-2, 4-HEXADIYNE (CI.CH2C i 0-)3 (self-reactive) 1, 6-dichloro-2, 4-hexadiyne is shock-sensitive. P. E. Drieder and H. V. Isaacson, Chem. Eng. News 50 (12): 51 (1972).

DICHLOROACETYLENE C1C i CC1 (self-reactive) During synthesis of dichloroacetylene, the dichloroacetyleae accidentally condensed and collected in a water trap. When the chemist attempted to sample the material in the trap, a violent explosion occurred. Since dichloroacetylene is reported to be shock-sensitive, the touching of the sample could have initiated the detonation. MCA Case History 1989 (1974).

DICHLOROETHYL ETHER CICH2CH2OCH2CH2C1 Chlorosulfonic Acid Mixing dichloroethyl ether and chlorosulfonic acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Notc under complete reference. Oleum Mixing dichloroethyl ether and oleum in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference.

DICYANDIAZIDE NCN :C(NNN)2 (self-reactive) Dicyandiazidc is a shock-sensitive compound. Chem. Eng. News 43 (52): 29, 30 (Dec. 27, 1965). 571 REVISIONS TO NFPA NO. 491M 491M-53

DIETHYL ETHER C2H.~OC'zH5 Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Die- thyl Ether. Chromic Anhydride See CHROMIC ANHYDRIDE plus Diethyl Ether.

DIETHYL PEROXYDICARBONATE [C2H~OC(O)C-]2 (self-reactive) Diethyl peroxydicarbonate decomposes rapidly at room temperature, sometimes with an explosion. It becomes hazardous above 10° C. One must avoid allowing it to crystallize. Kirk and Othmer, Second Ed. 14: 801, 803 (1963).

DIETHYL SULFATE (C2H50)2S02 Potassium Tert.- See ACETONE plus Potassium Tert.-Butoxide. Butoxide

DIETHYLENE GLYCOL MONOMETHYL ETHER CH3OCH2CH2OCH2CH20H Chlorosu]fonic Acid Mixing diethylcne glycol monomethyl ether and chlorosulfonic acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Oleum Mixing diethylene glycol monomethyl ether and oleum in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference.

DIETHYL PEROXIDE C2HsOOC~H5 (self-reactive) See OXYGEN plus Ethers.

DIETHYL ZINC (C2H~)2Zn Air Mellor 1:376 (1946-1947).

2, 4-DIETHYNYL-5-METHOXYTOLUENE (CHi C-)2C6H~(CH3)0CH3 (self-reactive) The polymer of this material explodes thermally. Chem. Abst. 75:19831 (1971). 572

491M-54 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

DIHYDRAZINOCUPRIC CHLORATE Cu(H2NNH2)2Ci08 See CUPRIC CHLORATE HYDRAZINATE.

DIHYDRAZINOZINC CHLORATE Zn(N2H4)2(CI0~)~ (self-reactive) This compound detonates when struck. Mellor 2, Supp. 1:592 (1956).

1, 6-DIIODO-2,4-HEXADIYNE (I.CH2Ci C-)~ (self-reactive) 1, 6-diiodo-2,4-hexadiyne is shock-sensitive. P. E. Drieder and H. V. Isaaeson, Chem. Eng. News 50 (12): 51 (1972).

DIISOBUTYLENE CH~:C(CH,)CH~C(CH,), Chorosulfonic Acid Mixing diisobutylene and chlorosulfonic acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Oleum Mixing diisobutylene and oleum in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Sulfuric Acid Mixing diisobutylene and 96% sulfuric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference.

DIISOPROPYL ETHER (CH3)~CHOCH(CH3)2 Air A flask of diisopropyi ether was being heated on a steam bath with gentle shaking when an explosion occurred. In a second instance, an explosion occurred after practically all the ether had been distilled. MCA Guide for Safety, Appendix 3 (1972). Chlorosulfonic Acid Mixing diisopropyl ether and chlorosulfonic acid in a closed container caused the temperature and pressure to increase. Flynn qnd Rossow (1970). See Note under complete reference. Nitric Acid Mixing diisopropyl ether and 70% nitric acid in a closed container, caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. 573 REVISIONS TO NFPA NO. 491M 491M-55

DIISOPROPYL PEROXYDICARBONATE [(CH~)2CHOC(0)0-h (sel.f-reactive) Diisopropyl perdicarbonate decomposes rapidly at room temperature and sometimes explodes. It becomes hazardous above 10° C. It should notbe allowcd to crystallize. Kirk and Othmer, Second Ed. 14: 801, 803 (1963). Organic Matter Upon contact with diisopropyl peroxydicarbonate, combustible organic materials can ignite or explode. Haz. Chem. Data p. 121 (1973).

DIMETHYL. CARBONATE CHaOCO.~OCH3 Potassium Tert.- See ACETONE plus Potassium Tert.-Butoxide. Butoxide

DIMETHYL ETHER CH3OCH3 Lithium Aluminum See LITHIUM ALUMINUM HYDRIDE Hydride plus Dimcthyl Ether.

DIMETHYL FORMAMIDE OCHN(CH3)2 Bromine ,See BROMINE plus Dimcthyl Formamide. Carbon Tetrachloride Dimethyl formamide and carbon tetrachloride react violently at temperatures above 65 ° C. Kittila, p. 165 (1967). Chlorinated Some halogenated hydrocarbons reacted with Hydrocarbons dimethyl formamide in the presence of iron at moderate temperatures. Kittila, p. 165 (1967). Hexachlor.obenzene Dimethyl formamide and hexachlorobenzene react violently above 65 ° C. Kittila, p. 165 (1967). Magnesium Nitrate This mixture undergoes spontaneous decomposition. Nitrates of sodium, lithium, lead, .copper and silver do not react under similar conditions. Kittila,p. 165 (1967). Methylene Methylene diisocyanate polymerized violently Diisocyanatc on contact with dimethyl formamide. Kittila, p. 122 (1967). Phosphorus Trioxide Dimethyl formamide, dimethyl sulfoxide, di- • methyl sulfitc, or methanol and phosphorus trioxide react ve15~ violently, often charring. Mellor 8, Supp. 3:382 (1971).

DIMETHYLHYDRAZINE (CH3)2NNH2 Nitric Acid See NITRIC ACID plus l)imethylhydrazine. 574 491M-56 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

DIMETHYL MALONATE CH2(COOCH3)2 Methyl Azidc See METHYL AZIDE plus Dimethyl Malo- nate.

DIMETHYL SULFITE S03(CH~)2 Phosphorus Trioxide See DIMETHYL FORMAMIDE plus Phos- phorus Trioxide.

DIMETHYL SULFOXIDE (CH3)2S0 Methyl Bromide See METHYL BROMIDE plus Dimethyl Sulfoxide. Phosphorus Trioxide See DIMETHYL FORMAMIDE plus Phos- phorus Trioxide:

DINITROANILINE HYDROCHLORIDE (02N)2C6H3NHfHC1 Nitrosylsulfuric Acid See NITROSYLSULFURIC.ACID plus Di- nitroaniline Hydrochloride.

2, 4-DINITROBENZENE SULFENYL CHLORIDE (NO2)2C6H3SC1 (self-reactive) An explosion may occur when the solvent sym- metrical tetrachlorethane is ahnost removed in the chlorinolysis of 2, 4-ditfitrophenyl disulfide. MCA Guide for Safety, Appendix 3 (1972).

2, 4-DINITROCHLOROBENZENE (O2N)~C6H~CI (self-reactive) B.D. I-Ialpern, Chem. and Eng. News, 29: 2666 (1951).

DINITROGEN PENTOXIDE" 02NON02 Ozone See OZONE plus Dinitrogen Pentoxide.

'3, 5-DINITRO-4-HYDROXYBENZENEARSONIC ACID 4, 3, 5, 1-OHCeH2(NO2)2AsOaH2 (self-reactive) This compound and its metallic salts may be as explosive as its close relative picric acid. When a wet cake of the acid was heated an explosion occurred that was accomparfied by liberation of arse,fic or arsine. M. A. Phillips, Chem. & Ind. 1947: 61.

2," 4-DINITROPHENYL DISULFIDE [(02N)2C6H3S-]2 Tetrachlorethane See 2, 4-DINITROBENZENE SULFENYL- \ CHLORIDE (self-reactive). 575 REVISIONS TO NFPA NO. 491M 491M-57

DIOXANE 0CH2CH~OCH2CH2 I l Silver Perchlorate See SILVER PERCHLORATE plus Toluene. DIPEROXYTEREPHTHALIC ACID (HOOOC)2C6H4 (self-reactive) This acid explodes under the influence of a shock or an increase in temperature. Chem. Reviews 45: 14, 15 (1949).

DIPHENYLTETRACETYLENE (C6H5C:CC:C)2 (self-reactive) Diphenyltetracetylene was stable for at least 13 months at room temperature in the dark. When placed on a metallic plate, it decomposed explosively with much soot. Chem. Abst. 45:7082 (1962):

DIPHOSPHINE H~PPH2 Air Diphosphine is spontaneously flammable in air. Mellor 1:376 (1946-1947). Mellor 8, Supp. 3:273 (1971).

DIPROPARGYL ETHER (CH ! CCH2)~O Air An explosion occurred in a 50ogallon stainless steel still during the distillation of dipropargyl ether. MCA Guide for Safety, Appendix 3 (1972).

DISODIUM NITRITE Na2N02 (self-reactive) See POTASSIUM plus Sodium Nitrite and' Ammonia.

2, 6-DI.t-BUTYL-4 NITROPHENOL HOC6H3[C(CH3)2CH3]2 (self-reactive) This material exploded violently after being warmed for two to three minutes on a steam bath. ASESB Expl. Report 24 (1961).

ENDRIN CI~HsOC16 Parathion See PARATHION plus Eadrin. EPICHLOROHYDRIN OCH,.CHCH2CI 2-Aminoethaaol See 2-AMINOETHANOL plus Epichloro- hydrin. Chlorosulfonic Acid Mixing epichlorohydrin and 2-aminoethanol in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. 576

491M-58 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

Ethyleue Diamine See ETHYLENE DIAMINE plus Epichloro- hydrin. Ethyleneimine Mixing epichlorohydrin and ethyleneimine in ~/ ~losed contai~ter caused the temperature and pressure to iuerease. l,'lynn and Rossow (1970). See Note under complete reference. Nitric Acid M!xiug epichlorohydrin and 700-/o nitric acid iu a closed contailter caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Oleum Mixing epichlorohydriit and oleum in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). SEe Note uuder complete refere~me. Potassium Tert.- See ACETONE plus Potassium Tert.-Butoxide. Butoxidc Sulfuric Acid Mixing epichlorohydrin and 96~0 sulfuric acid ia a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference.

ERBIUM PERCHLORATE Er(CI04)2 Acetonitrile See ACETONITRILE plus Erbium Perchlo- rate.

ETHANE C~H6 Chlorine Dioxide See CHLORINE DIOXIDE plus Butadiene.

1, 2-ETHANETHIOL HSCH~CH2SH Calcium Hypochlorite See CALCIUM HYPOCHLORITE plus 1- Propanethiol.

ETHERS Boron Triiodide See BORON TRIIOD1DE plus Ethers.

ETHYL ACETATE C~H6COOCH3 Chlorosulfonic Acid Mixing ethyl acetate snd chlorosulfonic acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. 577 REVISIONS TO NFPA NO. 491M 491M-59

Lithium Aluminum See 2-CHLOROMETHYLFURAN plus Lith- Hydride and ium Aluminum Hydride and Ethyl Acetate. 2-Chloromethylfuran Oleum Mixing ethylacctate and oleum in a closed container caused the temperature alld pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Potassium Tert.- See ACETONE plus Potassium Tert.-Butoxide. Butoxide

ETHYL ACETOACETATE C2H~OCO.CH2CO.CH3 Tribromoneopentyl Tribromoncopentyl alcohol, ethyl acetoacetate Alcohol and Zinc and zinc were beiqg reacted to prepare the zinc chelate of tribromoneopentyl acetoacetate. When the reaction had proceeded to where 80% of the by-product ethanol had been removed, a violent decomposition occurred. Wischmeyer (1972). U.S. Pat. 3, 578, 619 (1971).

ETHYL ACRYLATE C~HbOCO.CH :CH~ Chlorosulfonie Acid Mixing ethyl acrylate and chlorosulfonic acid in a closed container caused the temperature and pressure to increase. ],'lynn and Rossow (1970). See Note under complete reference.

ETHYL ALCOHOL CHaCH~OH Bromine Pentafluoride See BROMINE PENTAFLUORIDE plus Acetic Acid. Chloriae Trioxide See CHLORINE TRIOXIDE plus Alcohol. Cyanuric Acid See CYANURIC ACID plus Water. Perchlorates See PERCHLORATES plus Benzeae. Perchloric Acid See PERCHLORIC ACID plus Ethyl Alcohol. Potassium Tert.- See ACETONE plus Potassium Tert.-Butoxide. Butoxide Uranyl Perchlorate See URANYL PERCHLORATE plus Ethyl Alcohol.

ETHYL AZODICARBOXYLATE C2HsOCO.N:NCO.OC~H5 (self-reactive) A sample decomposed upon attempted distillation with sufficient violence to shatter the distillation apparatus. .. Org. Syntheses 28, p. 59 (1948). 578 491M-60 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

ETHYLENE CH2:CH2 Bromo- See BROMOTRICHLOROMETHANE plus trichloromethaue Ethylene. Chloriae l)ioxide See CHLORINE DIOXIDE plus 13utadieue.

ETHYLENE CHLOROHYDRIN CICH2CH20H Chlorosulfouic Acid Mixing ethyleae chlorohydrin and chlorosulfonic acid in a closed coutainer caused the tempcrature and pressure to increase. l,'lynn and Rossow (1970). See Note under complete reference. Ethylene Diamine Mixing ethyleue chlorohydriu and ethylene diamiue in a closed co,~taiuer caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference.

ETHYLENE CYANOHYDRIN HOCH2CH2CN Chlorosulfonic Acid Mixing ethylene cyauohydritt and chlorosulfonic acid iu a closed coatainer caused the temperature aud pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Oleum See OLEUM plus Ethylene Cyauohydriu. Sodium Hydroxide See SODIUM HYDROXIDE plus Ethylene Cyanohydrin. Sulfuric Acid Mixing cthylene cyanohydriu aud 96% sulfuric ackl in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. ETHYLENE DIAMINE H2NCH2CH2NH2 Acetic Acid See ACETIC ACID plus Ethylene Diamine. Acetic Anhydride See ACETIC ANHYDRIDE plus Ethylene Diamine. Acrolein See ACROLEIN plus Ethylene Diamine. Acrylic Acid Sec ACRYLIC ACID plus Ethylene Diamine. Acrylonitrile Sec ACRYLONITRILE plus Ethylene Dia- mine. Allyl Chloride See ALLYL CHLORIDE plus Ethylene Dia- milm. Carbon Disulfide See CARBON DISULFIDE plus Ethylene Diamine. 579 REVISIONS TO NFPA NO. 491M 491M-61

Chlorosulfonic Acid Mixing ethylene diamine and chlorosulfonic acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Epichlorohydrin Mixing ethylene diamine and epichlorohydrin in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Ethylene Chlorohydrin See ETHYLENE CHLOROHYDRIN plus Ethylene Diamine. Hydrochloric Acid Mixing ethylene diamine and 36% hydrochloric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossmv (1970). See Note under complete reference. Mesityl Oxide See MESITYL OXIDE plus Ethylene Din- mine. Nitric Acid Mixing ethylene diamine and 70% nitric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Oleum Mixing ethylene diamine and oleum in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Propiolactone (BETA-) Mixing ethylene diamine' and propiolactone (BETA-) in a closed container caused the temperature add pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Sulfuric Acid Mixing ethylene diamine and 96% sulfuric aicd in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Vinyl Acetate Mixing ethylenc diamine and vinylacetate in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. 580 491M-62 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

ETHYLENE DICHLORIDE CICH2CH2CI Ammonia See AMMONIA plus Ethylene Dichloride. Dimethyl Amino A tank of dimethyl anfine propyl amine ex- Propyl Amine ploded violently when it reacted with wet ethylene dichloride which had been the tank's previous contents. Investigatiou revealed that this combination can be extremely hazardous. Doyle (1973).

ETHYLENE GLYCOL HOC2H,OH Chlorosulfonic Acid Mixing ethylene glycol and chlorosulfonic acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Oleum Mixing ethylene glycol and oleum ia a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Sulfuric Acid Mixing ethylene glycol and 96% sulfuric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference.

ETHYLENE GLYCOL MONOETHYL ETHER ACETATE CH3COOCH~CH~OCH2CH2OC~H5 Chlorosulfonic Acid Mixing ethyl glycol monoethyl ether acetate and chlorosulfouie acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Oleum Mixing ethylene glycol mouoethyl ether acetate and oleum in a closed container caused the temperature and pressure to it~crease. Flynn and Rossow (1970). See Note under complete reference.

ETHYLENEIMINE NHCH2CH2 I__1 Acetic Acid See ACETIC ACID plus Ethyleneimine. Acetic Aldaydride See ACETIC ANHYDRIDE plus Ethylel~ei- mine. Acrolein See ACROLEIN plus Ethyleneimine. Acrylic Acid See ACRYLIC ACID plus Ethyleneimine. 581 REVISIONS TO NFPA NO. 491M 491M-63

Allyl Chloride Sec ALLYL CHLORIDE plus Ethyleneimine. Carbon Disulfide See CARBON DISULFIDE plus Ethyleuei- mine. Chlorosulfonic Acid Mixing ethyleneimine and chlorosulfonic acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Epichlorohydrin See EPICHLOROHYDRIN plus Ethylenei- mine. Glyoxal See GLYOXAL plus Ethyleneimine. Hydrochloric Acid Mixing ethyleneimine and 36% hydrochloric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note uuder complete reference. Hydrofluoric Acid Mixing ethyleneimine and 48.7% hydrofluoric acid in a closed col~tainer caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Nitric Acid Mixing ethyleneimine and 70% nitric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete refercace. Oleum See OLEUM plus Ethyleaeimine. Propiolactone (BETA-) Mixing ethyleneimine and propiolaetolie (nETA-) in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Sulfuric Acid Mixing ethyleneimine ~nd 96% sulfuric acid in a'elosed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Vinyl Acetate See VINYL ACETATE plus Ethylelmimme.

ETHYL HYPOCHLORITE CH3CH20CI (self-reactive) Ethyl hypochlorite decomposes explosively when exposed to light and rapidly even in its absence. Mellor 2, Supp. l: 560 (1956)• See also ALCOHOLS plus Hypochlorous Acid. 582 491M-64 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

ETHYL SODIO-ACETOACETATE NaOC(CH3):CHCO.504C2I-[5 2-Iodo-3, See 2-IOD0-3, 5-DINITROBIPHENYL plus 5-Dinitrobiphenyl Ethyl Sodio-Acetoacetate. FERRIC BROMIDE, FeBr3 Potassium • See POTASSIUM plus Boroa Tribromide. Sodium See SODIUM plus Cobaltous Bromide. FERRIC CHLORIDE FeC13 Allyl Chloride See SULFURIC ACID plus Allyl Chloride. Potassium SeePOTASSIUM plus Boron Tribromide. Sodium See SODIUM plus Cobaltous Bromide. FERRIC HYPOPHOSPHITE Fe(PH20~)3 (self-reactive) Ferric hypophosphite forms impact-sensitive .ammmfition-primi~lgmixtures. Mellor 8, Supp. 3:623 (1971). FERROUS BROMIDE FeBr~ Potassium See POTASSIUM plus Boroa Tribromide. Sodium See SODIUM plus Cobaltous Bromide. FERROUS CHLORIDE FeCI~ Potassium See POTASSIUM Plus Boron Tribromide. Sodium See SODIUM plus Ferrous Chloride. FERROUS IODIDE FeI~ Potassium See POTASSIUM plus Boron Tribromide. Sodium See SODIUM plus Cobaltous Bromide. FERROUS SULFIDE FeS Hydrogen Peroxide See ANTIMONY ~TRISULFIDE plus Hydro- gen Peroxide. Lithium See LITHIUM plus Ferrous Sulfide. FLUORAZIDE N3F (self-reactive) See FLUORINE AZIDE. (Self-reactive). FLUORINE F~ Alkenes Fluorine causes unsaturated hydrocarbons to ignite spontaneously. MeUor 2, Supp. 1:55 (1956). Alkylbettzenes Fluorine causes aromatic hydrocarbons to ignite spontaneously. Mellor 2, Supp. 1:55 (1956). Ammouia Mellor 8, Supp. 2:329 (1964). Ammonium Hydroxide Combination of fluorine and ammonium hydroxide results ill flames aud explosion. Mellor 2, Supp. 1:56 (1956). 583 REVISIONS TO NFPA NO. 491M 491M-65

Carbon MeUor 2, Supp. 1:60 (1956). Cellulose Fluorine in contact with cotton produces a violent explosion. MeUor 2, Supp. 1:54 (1956). Chlorine See CHLORINE plus Fluorine. Chlorine Dioxide Mellor 2, Supp. l: 532 (1956). Chromyl Chloride Fluorine reacts with chromyl chloride, producing flame at certain concentrations. MeUor 2, Supp. 1:64 (1956). Hydrazine Spontaneous ignition occurs when these chemicals are mixed. Mellor 8, Supp. 2:95 (1967). Hydrocarbons Mellor 2,Supp. 1 : 55 (1956). Hydrogen .Fluorine and hydrogen react as low as minus 210 ° C when impurities are present. MeUor 1:327 (1946-1947). Iridium See IRIDIUM plus Fluorine. Manganous Oxide See FLUORINE plus Trimanganese Tetroxide. Mercuric Cyanide Fluorine and mercuric cyanide react vigorously when gently heated, producing flames. MeUor 2, Supp. 1:63 (1956). Neoprene Mellor 2, Supp. 1:54 (1956). Nitric Acid Fluorine in contact with nitric acid creates a danger of explosion if acid is not 100% strength. Mellor 8, Supp. 2:319 (1967). Nitric Oxide MeUor 2, Supp. 1:54 (1956). Nitrogen Dioxide Fluorine and nitrogen dioxide react vigorously when heated. Mellor 2, Supp. 1:54 (1956). •Organic Matter Fluorine in contact with leather causes it to (Leather) smolder and char. Mellor 2, Supp. 1:54 (1956). Perchloric Acid Reaction of fluorine and perchloric acid produces fluorine perchlorate, a highly reactive material. Mellor 2, Supp. 1:59 (1956). See also FLUORINE PERCHLORATE (self- reactive). The action of fluorine gas in 60-72% perchlorie acid leads to the formation of fluorine perchlo. rate, a very unstable gas that explodes under the most diverse physical and chemical in- fluences. Pascal 16:316 (1931-1934). Kirk and Othmer, Second Ed. 5:74 (1963). 584 491M-66 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES Fluorine (cont.) Phosphorus Mellor 2, Supp. 1 : 60 (1956). See also PHOSPHORUS plus Chlorine. Potassium Nitrate Fluorine attacks potassium nitrate to give fluorine nitrate. Mellor 2, Supp. l: 62 (1956). See also FLUORINE NITRATE (self-reactive). Potassium Perchlorate The action at low pressure of fluorine on potassit~m perchlorate produces fluorine perchlorate, which is very unstable and explodes easily. Pascal 16:316 (1931-1934). Rhenium See RHENIUM plus Fluorine. Silver Cyanide Fluorine and silver cyanide react with explosive violence at ordinary temperatures. Mellor 2, Supp. 1:63 (1956). Sodium Acetate Fluorine and sodium acetate produce an explosive reaction involving formation of diacetyl peroxide. Mellor 2, Supp. 1:56 (1956). See also DIACETYL PEROXIDE (self- reactive). Strontium Phosphide Mixtures of these materials ignite at room temperatures. MeUor 8:841 (1946-1947). Tantalum Fluorine reacts vigorously with tantalum. The metal should not be used to handle it. Mellor 2, Supp. l: 62 (1956). Thallous Chloride Fluorine and thallous chloride react violently, melting the product. Mellor 2, Supp. 1:63 (1956). Trimanganese Fluorine and trimanganese tetroxide or man- Tetroxide ganous oxide react vigorously below 100 ° C, even when diluted with nitrogen. MeUor 2, Supp. 1:64 (1956). Trimanganese Fluoriue and trinmnganese tetroxide react" Tetroxide vigorously below 100 ° C, even when diluted with nitrogen. Mellor 2, Supp. 1:64 (1956).

FLUORINE AZIDE N3F (self-rcactive) Fluorine ~zide is extremely unstable aud easily decomposes explosively. Mellor 2, Supp. 1" 59 (1956). MeUor 8, Supp. 2:24 (1967). 585

REVISIONS TO NFPA NO. 491M 491M-67

FLUORINE NITRATE FNO3 (self-reactive) Fluorine nitrate explodes on slight concussion. Merck Index, p. 464 (1968). FLUORINE PERCHLORATE FCIO~ (self-reactive) Mellor 2, Supp. l : 59, 184 (1956). See also POTASSIUM PERCHLORATE plus Fluorine. Organic Matter Fluorine perchlorate undergoes explosive decomposition on contact with grease, dirt, or rubber tubing. Mellor 2, Supp. 1:184 (1956). Potassium Iodide Fluorine perchlorate in contact with potassium iodide cau cause an explosion. Mellor 2, Supp. 1:184 (1956).

FLUORINE PEROXIDE F~02 (self-reactive) Fluorine peroxide is a very unstable vapor above minus 100 ° C, decomposing to fluorine and oxygen gases. Mellor 2, Supp. 1: 194 (1956). FORMALDEHYDE HCHO Nitrogen Dioxide The slow reaction between nitrogen dioxide and formaldehyde becomes explosive in the. region of 180° C. F. H. Pollard and P. Woodward, Trans. Fara- day Soc. 45:767-770 (1949). Performic Acid See PERFORMIC ACID plus FormMdehyde.

FORMIC ACID HCO.OH Furfuryl Alcohol See FURFURYL ALCOHOL plus Formic Acid. Thallium Trinitrate See THALLIUM TRINITRATE TRIHY- Trihydrate DRATE plus Formic Acid.

2-FURAN PEROXYCARBOXYLIC ACID OCH:CHCHCCOO.OH (self-reactive) I J This acid explodes when heated to 30 to 40 ° C, or at room temperature upon addition of organic or inorganic materials such as carbon black, calcium chloride, barium chloride, strontium chloride or magnesium chloride. Chem. Reviews 45: 15, 16 (1949).

FURFURYL ALCOHOL 0CH:CHCH:CCH20H Nitric Acid See NITRIC ACID plus Furfuryl Alcohol. See also NITRIC ACID plus Diborane. 586 491M-68 REPORT OF CO*i~IITTEE ON CI-IEMICALS AND EXPLOSIVES

GALLIUM PERCHLORATE Ga(CI03)3 Urea The double salt formed decomposes violently on heating. Mellor 2, Supp. 1:611 (1956). GLASS Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Char- coal. GLYCERIDES (RCO.OCH~)CHOCO.R Nitric Acid and See NITRIC ACID plus Sulfuric Acid and Sulfuric Acid Glycerides. GLYCEROL HOCH2CHOHCH2OH Chlorine See CHLORINE plus Polypropylene. Silver Perchlorate See SILVER PERCHLORATE plus Acetic Acid. GLYOXAL OCHCHO Chlorosulfonic Acid Mixing glyoxal and ehlorosulfonic acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Ethyleneimine Mixing glyoxal and ethyleneimine in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Nitric Acid See NITRIC ACID plus Glyoxal. Oleum Mixing glyoxal and oleum in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Sodium Hydroxide See SODIUM HYDROXIDE plus Glyoxal. GOLD Au Hydrogen Peroxide Finely divided gold and a strong hydrogen peroxide solution may explode. Mellor 1:936 (1946-1947). GOLD SALTS Nitromethane See COPPER SALTS plus Nitromethane.

GRAPHITE C Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Char- coal. Potassium See POTASSIUM plus Charcoal. 587 REVISIONS TO NFPA NO. 491M 491M-69

GUANIDINE NITRATE H~NC(NH)NH2.HN03 (self-reactive) See AMMONIUM THIOCYANATE plus ' Lead Nitrate. HALOGEN FLUORIDES Organic Matter See BROMINE MONOFLUORIDE plus Water. See individual fluoride plus Organic M~tter. tlEPTANE CTHI6 Phosphorus and See PHOSPHORUS plus Chlorine and Hep- Chlorinc tane.

HEXABORON DODECAHYDRIDE B6Hn Air This hydride is spontaneously flammable in air. Mellor 5:36 (1946-1947).

HEXACHLOROBENZENE C6C16 Dimethyl Formamide See DIMETHYL FORMAMIDE plus Hexa- ehlorobenzene.

2, 4-HEXADIYN-I, 6-BISCHLOROSULFITE (CISO.OCH2C!C-)~ (self-reactive) See THIONYL CHLORIDE plus 2, 4-Hexa- diyn-1, 6-Diol.

2, 4-HEXADIYN-1, 6-BISCHLOROSULFITE (CISO.OCH2C!C-)~ (self-reactive) 2, 4-hexadiyn-1, 6-bisehlorosulfite is shock- sensitive and decomposes violently upon distillation. P. E. Drieder and H. V. Isaacson, Chem. Eng. News 50 (12): 51 (1972). 2, 4-HEXADIYN-1, 6-DIOL (HOCH~CIC-)2 Phosgene See PHOSGENE plus 2, 4-Hexadiyn-1, 6-Diol. Thionyl Chloride See THIONYL CHLORIDE plus 2, 4-Hexa- diyn-1, 6-diol. HEXAMETHYLBENZENE C6(CH3)6 Nitrometlm~m The electro-oxidation of various methyl benzenes was being studied. During the reactions, violent explosions occurred at the auxiliary electrode. . Chem. Eng. News 49 (23) : 6 (1971). HEXAMMINOCADMIUM CHLORATE Cd(NH3)~(CI03)2 (self-reactive) This compound detonates when struck. MeUor 2, Supp. 1:592 (1956). 588

401M-70 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

HEXAMMINOCADMIUM PERCHLORATE Cd(NH3)6 (C1002 (self-.reactive) This compound detonates when struck, but is less sensitive than hexamminocadmium chlorate. MeUor 2, Supp. 1:592 (1956).

HEXAMMINOGOBALT CHLORATE Co(NH3)6(C103)2 (self-reactive) This compound detonates when struck. MeUor 2, Supp. 1:592 (1956).

HEXAMMINOCOBALTIC CHLORITE Co(NHs)sCIOs.3H20 (self-reactive) Hexamminocobaltic chlorite contains an explosive combination of ions. MeUor 2, Supp. 1:575 (1956).

HEXAMMINOCOBALT PERCHLORATE Co(NHa)6(CIO~)2 (self-reactive) This compound detonates when struck but is less sensitive than hexamminocobalt chlorate. MeUor 2, Supp. 1:592 (1956).

HEXAMMINONICKEL CHLORATE Ni(NH3)6(CI03)~ (self-reactive) This compound detonates when struck. MeUor 2, Supp. 1:592 (1956).

HEXAMMINONIGKEL PERGHLORATE Ni(NHa)6(CI04)2 (self-reactive) This compound detonates when struck but is less sensitive than hexamminonickel chlorate. MeUor 2, Supp. 1:592 (1956).

HYDRAZINE H~NNH2 Air Mellor 8, Supp. 2:95 (1967). Alkali Metals and Explosive metal hydrazides form when hy- Ammonia drazine and alkali metals are mixed in liquid ammonia. MeUor 8, Supp. 2:73 (1967). Cupric Salts See CUPRIC SALTS plus Hydrazine. Fluorine See FLUORINE plus Hydrazine. Hydrogen Peroxide Mellor 8, Supp. 2:95 (1967). Iron Oxide While boiling a sample of a polyester fiber in hydrazine in a glass beaker, the technician used a somewhat rusty pair of metal tweezers to handle the sample. When the tweezers were put in the solution, the solution ignited. The ignition temperature of hydrazine varies from 75 ° F in the p~'esenee of iron oxide to 518 ° F in a glass container. MCA Case History 1893 (1973). 589 :REVISIONS TO NFPA NO. 491M 491M-71

Nickel See NICKEL plus Hydrazine Nitric Acid Spontaneous ignition occurs when these chemicals are mixed. Mellor 8, SUpp. 2:95 (1967). Nitrous Oxide See NITROUS OXIDE plus Lithium Hydride. Oxygen See OXYGEN plus Hydrazine. Oxygen (liquid) See OXYGEN (LIQUID) plus Hydrazine. Potassium Dichromate See POTASSIUM DICHROMATE plus Hy- drazine. Sodium Dichromate See POTASSIUM DICHROMATE plus Hy- drazine.

HYDRAZINE AZIDE H2NNH3N3 (self-reactive) This is an explosive salt. Mellor 8, Supp. 2:86 (1967).

HYDRAZINE CHLORITE . H:NNH2CI02 (self-reactive) This is an explosive salt, highly flammable when dry. Mellor 8, Supp. 2:85 (1967). Mellor 2, Supp. 1:573 (1956).

HYDRAZINE NITRATE H2NNH3NO~ (self-reactive) This explosive salt is less stable than ammonium rtitrate. Mellor 8, Supp. 2:86 (1967).

HYDRAZINE PERCHLORATE H2NNH2CI04 (self-reactive) MeUor 8, Supp. 2:85 (1967).

HYDRAZINE SELENATE H2NNH2SeO30H (self-reactive) This salt is explosive. Mcllor 8, Supp. 2:85 (1967).

HYDRAZOIC ACID N3H Cadmium See CADMIUM plus Hydrazoic Acid. Copper Sec COPPER plus Hydrazoic Acid. Nickel See NICKEL plus Hydrazoic Acid. Nitric Acid The reaction of hydrazoic acid and nitric acid is energetic. MeUor 8, Supp. 2:4 (1967).

HYDROCARBONS Chlorine See CHLORINE plus Hydrocarbons. Magnesium See MAGNESIUM PERCHLORATE plus Perchloratc Hydrocarbons. 590 491M-72 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

HYDROCHLORIC ACID' HCI Acetic Anhydride See ACETIC ANHYDRIDE plus Hydro- chloric Acid. 2-Aminoethanol See 2-Aminoethanol plus Hydrochloric .~cid. Ammonium Hydroxide Mixing hydrochloric acid ~llC[ 280~0 ammonia in a closed contai~ler caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Calcium Phosphide See CALCIUM PHOSPHIDE plus Hydro- chloric Acid. Chlorosulfonic Acid See CHLOROSULFONIC ACID plus Hydro- chloric Acid. Ethylene Diamine See ETHYLENE I)IAMINE plus Hydro- chloric Acid. Ethyleneimine See ETHYLENEIMINE plus Hydrochloric Acid. Oleum See 0LEUM plus Hydrochloric Acid. Perchloric Acid The hydronium compouud decomposes spontaneously with violence. Mellor 2, Supp. 1:613 (1956). Propiolactone (BETh-) See PROPIOLACTONE (~ETA-) plUS Hydro- chloric Acid. Propylene Oxide See PROPYLENE OXIDE plus Hydro- chloric Acid. Silver Perchlorate and See SILVER PERCHLORATE plus Carbon Carbon Tetrachloride and Hydrochloric Acid. Tetrachloride Sodium Hydroxide See SODIUM HYDROXIDE plus Hydro- chloric Acid. Sulfuric Acid Mixing 36% hydrochloric acid and 96% sulfuric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Uranium Phosphide See URANIUM PHOSPHIDE |)lus Hydro- chloric Acid. Vinyl Acetate See VINYL ACETATE plus Hydrochloric Acid.

HYDROFLUORIC ACID HF Acetic Anhydride See ~CETIC ANHYDRIDE plus Hydrofluoric Acid. 2-Aminoethanol See 2-AMINOETHANOL plus Hydrofluoric Acid. 591 REVISIONS TO NFPA NO. 491M 491M-73

Ammonium Hydroxide Mixing 48.7% hydrofluoric acid and 28% anamonia in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reterence. Calcium Oxide See CALCIUM OXIDE plus Hydrofuoric Acid. Chlorosulfonic Acid See CHLOROSULFONIC ACID plus Hydro- fluoric Acid. Ethylene Diaminc See ETHYLENE DIAMINE plus Hydro- fluoric Acid. Ethyleneimine See ETHYLENEIMINE plus Hydrofluoric Acid. Oleum Sec OLEUM plus Hydrofluoric Acid. Propiolactone (BETA- See PROPIOLACTONE (m~TA-) plus Hydro- fluoric Acid. Propylene Oxide See PROPYLENE OXIDE plus Hydrofluoric Acid. Sodium Hydroxide See SODIUM HYDROXII)E plus Hydro- fluoric Acld. Sulfuric Acid Mixing 48.7% hydrofluoric acid and 96% sulfuric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note trader complete reference. Vinyl Acetate See VINYL ACETATE plus Hydrofluoric Acid.

HYDROGEN H,2 Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Am- monia. Lithium See LITHIUM plus Hydrogen. Oxygen Difluoride Mixtures of hydrogen, carbon monoxide, or methane and oxygen difluoridc are exploded when ,'L spark is discharged. MeUor 2, Supp. 1:192 (1956).

HYDROGEN BROMIDE HBr Ammonia The reaction is vigorous even at minus 80 ° C with intensely dried reactants. Mellor 2, Supp. 1:737 (1956). Ozone See OZONE l~lus Hydrogen Bromide.

HYDROGEN CHLORIDE HCI Mercuric Sulfate See MERCURIC SULFATE plus Hydrogen Chloride. Sodium . See SODIUM l)lus Hydrogen Chloride. 592 491M-74 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

HYDROGEN IODIDE Ozone See OZONE plus Hydrogen Iodide.

HYDROGEN PEROXIDE H,,Oo. Acetic Anhydride Addition of hydrogen peroxide to acetic anhydride yields peroxyacetic acid; but an excess of acetic anhydride reacts with peroxyacetic acid yielding diacetyl peroxide, which is very unstable and explodes readily. Chem. Reviews 45:5 (1949). Sec also HYDROGEN PEROXIDE plus Acetic Acid. See also PERACETIC ACID plus Acetic Anhydride. Antimony Trisulfide See ANTIMONY TRISULFIDE plus Hydro- gen Peroxide. Arsenic Trisulfide See ANTIMONY TRISULFIDE plus Hydro- gen Peroxide. t-Butyl Alcohol The preparation of di tertiary butyl peroxide by thc addition of tertiary butyl alcohol to a mixture of hydrogen peroxide and sulfuric acid (2 to 1 weight ratio of'78% sulfuric acid to 50% hydrogen peroxide) has resulted in severe ex- "plosions particularly during the early stages of large batches. T. A. Schenach, Chem. Eng. News. 51 (6): 39 (Feb. 5, 1973). Cellulose Hydrogexl peroxide plus cellulose (in cotton) • ignites spontaneously. Mellor 1:938 (1946-1947). Chlorine and See CHLORINE plus Hydrogen Peroxide and Potassium Potassium Hydroxide. Hydroxide Chlorosulfonic Acid See CHLOROSULFONIC ACID plus Hy- drogen Peroxide. Cupric Sulfide See ANTIMONY TRISULFIDE plus Hydro- gen Peroxide. Ferrous Sulfide See ANTIMONY TRISULFIDE plus Hydro- gen Peroxide. Gold See GOLD plus Hydrogen Peroxide. Hydrazine See HYDRAZINE plus Hydrogen Peroxide• Hydrogen Selenide See HYDROGEN SELENIDE plus Hydro- gen Peroxide. Lead Dioxide See LEAD DIOX] DE plus Hydrogen Peroxide. Lead Monoxide See LEAD DIOXIDE plus Hydrogen Peroxide. Lead Sulfide See ANTIMONY TRISULFIDE plus Hydro- gen Peroxide. 593 REVISIONS TO NFPA NO. 491M 491M-75

Mercuric Oxide See LEAD DIOXIDE plus Hydrogen Per- oxide. Molybdenum Disulfide See ANTIMONY TRISULFIDE plus Hydro- gen Peroxide. Nitric Acid This mixture is unstable when more than 50% of acid is present. Mellor 8, Supp. 2:315 (1967). Potassium See LEAD DIOXIDE plus Hydrogen Per- oxide. Potassium See POTASSIUM PERMANGANATE plus Permanganate Hydrogen Peroxide. Silver See SILVER plus Hydrogen Peroxide. Sodium See LEAD DIOXIDE Pl~is Hydrogen Per- oxide. Sodium Iodate See SODIUM IODATE plus Hydrogen Per- oxide. Thiodiglycol See THIODIGLYCOL plus Hydrogen Per- oxide.

HYDROGEN SELENIDE Sell2 Hydrogen Peroxide Hydrogen selenide and hydrogen peroxide mldergo a very swift decomposition. Mellor 1 : 941 (1946-1947).

HYDROGEN SULFIDE H2S Bromine Pentafluoride See BROMINE PENTAFLUORIDE plus Acetic Acid. Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Am- monia. Oxygen Difluoride See OXYGEN DIFLUORIDE plus Hydrogen Sulfide. Sodium See SODIUM plus Hydrogen Sulfide.

HYDROGEN TELLURIDE H2Te Nitric Acid See NITRIC ACID plus Hydrogen Telluride.

HYDROXYLAMINE HYPOPHOSPHITE NH2OHPH202 . (self-reactive) Hydroxylamiue hypophosphite detonates above 100 ° C. Mellor 8 : 880 (1946-1947).

HYPOPHOSPHORIC ACID H4P~06 Mercuric Nitrate See MERCURIC NITRATE plus Hypo- phosphoric Acid. 594 i 491M-76 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

INDANE CH2CH :CHC6H4 , t t J Nitric Acid and In the prcl)aration of 4 and 5 nitroiudancs ac- Sulfuric Acid cording to the procedure of Lindncr and Brukin (Chem. Bet. 60, 435 (1925)) the crude nitro mix was distilled in vacuo. After allowing the pot to cool, air was admitted to the residuc. After a short period the pot erupted. A second preparation exploded at the beginning of the distillation. G. W. Grebblc, Chem. Eng. News 51 (6): 39 (Feb. 5, 1973).

IODINE I2 Ammonium The reaction of excess iodine with strong Hydroxide aqueous ammonium hydroxide forms explosive iodide. Mellor 8, Supp. 1:330 (1964). Nitrogen iodides, which detonate on drying, are formed from concentrated solutions. Mellor 2, Supp. 1:851 (1956). Bromine An immediate reaction with evolution of heat Pentafluo?ide occurs bctween iodine and bromine penta- fluoridc. Mellor 2, Supp. 1:173 (1956). Cesium Carbide Cesium carbide, rubidium carbide or lithium carbide (after warming) burn in iodine vapor. Mellor 5:848 (1946-1947). ~,.L', Chlorine See CHLORINE plus Iodine, Chlorine See CHLORINE TRIFLUORIDE plus Mer- Trifluoride curic Iodide. Lithium A highly luminous reaction occurs at room temperature, betwccn iodine and lithium, potassium, and sodium. Mellor 2, Supp. 1:848 (1956). Lithium Carbide See IODINE plus Cesium Carbide. Oxygen Difluoride See BROMINE plus Oxygen Difluoride. Phosphorus See also PHOSPHORUS plus Oxygen. Potassium Iodine and potassium vapors at 0.001 mm pressure react with luminescence. Mellor 2, Supp. 3:1563 (1963). Rubidium Carbide See IODINE plus Cesium Carbide.

IODINE AZIDE N~I (self-reactive) Iodine azide is spontaneously explosive. MeUor 8:336 (1946-1947). Mellor 8, Supp. 2:50 (1967). 595 REVISIONS TO NFPA NO. 491M 491M-77

IODINE HEPTAFLUORIDE IF7 Ammonium Bromide Iodine heptafluoride reacts violently with ammonium bromide, ammonium chloride or ammonium iodide. Mellor 2, Supp. 1:179 (1956). Ammonium Chloride See IODINE HEPTAFLUORIDE plus Am- monium Bromide. Ammonium Iodide See IODINE HEPTAFLUORIDE plus Am- monium Bromide. Carbon Monoxide Carbon monoxide burns in gaseous iodine heptafluoride. Mellor 2, Supp. 1:179 (1956). Organic Matter See BROMINE MONOFLUORIDE plus Water. Sulfuric Acid In reaction between iodine heptafluoride and sulfuric acid the acid becomes effervescent. Mellor 2, Supp. 1:185 (1956). Water See BROMINE MONOFLUORIDE plus Water.

IODINE MONOBROMIDE IBr Phosphorus See PHOSPHORUS plus Iodine Monobromide. Potassium See POTASSIUM plus Iodine Monobroinide. Sodium See SODIUM plus Ferrous Chloride. See SODIUM plus Iodine Monobromide.

IODINE MONOCHLORIDE 1CI Cadmium Sulfide The reaction between iodine monochloride and cadmium sulfide, lead sulfide; silver sulfide, or zinc sulfide is vigorous. Mellor 2, Supp. 1:502 (1956). Lead Sulfide See IODINE MONOCHLORIDE plus Cad- mium Sulfide. Organic Matter Iodinc monochloride produces a vigorous reaction with cork, rubber and other organic substances. MeUor 2, Supp. 1:500 (1956). Phosphorus See PHOSPHORUS plus Iodine Monobromide. Phosphorus Trichloride The reaction of iodiue monoehloride and phosphorus trichloride is intensely exothermal. Mellor 2, Supp. l • 502 (1956). Rubber See IODINE MONOCHLORIDE plus Or- ganic Matter. Silver Sulfide See IODINE MONOCHLORIDE plus Cad-- mium Sulfide. Sodium See SODIUM plus Iodine Monochloride. 596 491M-78 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

Zinc Sulfide See IODINE MONOCHLORIDE plus Cad- mium Sulfide.

IODINE PENTAFLUORIDE IF5 Organic Matter See also BROMINE MONOFLUORIDE plus Water. See also IODINE PENTAFLUORIDE plus Water. Tetraiodoethylene Explosions occur with too rapid admixture of iodine pentafluoride and tetraiodoethylene. Mellor 2, Supp. 1:176 (1956), Water The reaction between iodine petttafluoride and water is violent. Water-containing materials and many organics also react violently. Mellor 2, Supp. 1:176 (195,6). See also BROMINE MONOFLUORIDE plus water.

2-IODO-3, 5-DINITROBIPHENYL IC6H2(NO~),CsHs Ethyl Sodio- The condensation of 2-iodo-3, 5-dinitro- Acetoacetate biphenyl with ethyl sodio-aceto-acetate should be carried out with only 5-6 grams of the 2-iodo-3, 5-dinitrobiphenyl since larger amomlts lead to explosim~s. S. H. Zahur and I. K. Kocker. J. Indian Chem. Soc. 32:491 (1955).

3-IODO-I-PHENYL-1-PROPYNE C~HsCi C.CH2I (self-reactive) While being distilled at ~about 180 ° C 3-iodo- 1-phenyl-l-propyne deto~mted. Chem. Eng. New8 50 (23) : 86, 87 (June 5, 1972).

IODOFORM CHI3 Lithium See LITHIUM plus Bromoform.

IRIDIUM Ir Chlorine Trifluoride Mellor 2, Supp. 1:156 (1956). Fluorine Powdered iridium and fluorine react vigorously at 260 ° C, forming the hexafluoride. Mellor 2, Supp. 1:65 (1956). r Oxygen Di21uoride An incandescent reaction occurs when any of the following metals are warmed gently in gaseous oxygen difluoride: iridium, osmium, palladium, platinum, rhodium, ruthenium. Mellor 2, Supp. 1:192 (1956). 597

REVISIONS TO NFPA NO. 491M 491M-79

IRIDIUM-AMMINE NITRATES (self-reactive) Iridium-ammine nitrates may be impact- sensitive. Ir(Ntt3)5OH(NO3)3 and Ir (NH3)sCI(N03)3 detonate at red heat. Mellor 15: 787. (1946-1947).

IRIDIUM-AMMINE PERCHLORATES (self-reactive) Iridium-ammine perchlorates may be impact-sensitive. Mellor. 15:787 (1946-1947).

IRON Fe Chlorine- Mellor 2, Supp. 1:380 (1956). Chlorine Trifluoride Mellor 2, Supp. 1:156 (1956). Hydrogen Peroxide Iron and hydrogen peroxide ignite immediately if a trace of manganese dioxide is present. Mellor 1:938 (1946-1947). Phosphorus See COPPER plus Phosphorus. Sodium Carbide See MERCURY plus Sodium Carbide.

IRON ALLOYS (See LITHIUM plus Cobalt Alloys.)

IRON OXIDE Fe~03 Hydrazine See HYDRAZINE plus Iron Oxide.

ISOAMYL NITRITE (CH3)2CHCH2CH2ONO (self-reactive) Vapors will explode when heated. Von Schwartz and Salter, p. 322 (1940).

ISOBUTANETHIOL (CH3)2CHCH2SIt Calcium Hypochlorite See CALCIUM HYPOCHLORITE plus 1- Propanethiol.

ISOBUTYROPHENONE (CH3)2CHC :0(C6H5) Bromine See BROMINE plus Isobutyrophenone.

ISOPRENE CH2:C(CH3)CH:CH2 Chlorosulfonic Acid Mixing isoprene and chlorosulfonie acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. 598

491M-80 REPORT OF COMM[TTEE ON CHEMICALS AND EXPLOSIVES

Nitric Acid Mixing isoprene and 70% nitric ttcid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Oleum Mixing isoprene and oleum in a closed co~ltainer caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Sulfuric Acid Mixing isoprene and 96% sulfuric acid in closed container caused the temperature and pressurc to increase. Flynn and Rossow (1970). See Note under complete reference.

ISOPROPYL ALCOHOL (CH~)2CHOH Oleum See OLEUM plus [sopropyl Alcohol. Phosgene The reaction between isopropyl alcohol ~nd phosgene forms isopropyl chloroformate and hydrogen chloride, in the presence of iron salts thermal decomposition can occur, which in some cases can become explosive. Konstantinov, I. I, Pcrcslegina, L. S., Zhurav- lev, E. Z., and Gusty, Yu. M. Tr. po Khim. i Khim. Teknol. 10 (2): 171.--4 (1967). Potassium Tert.- Set ACETONE plus Potassium Tert.- Butoxide Butoxide.

ISOPROPYL CHLOROFORMATE. (CH3)~CHOCO.C1 (self-reactive) Isopropylchloroformate stored in ~ refrigerator exploded. Wisch~neger (1973). See also ISOPROPYL ALCOHOL plus Phos- gene.

ISOPROPYL HYPOCHLORITE (CHa)2CHOCI (self-reactivc) Isopropyl hypochloritc decomposes ext)losively when exposed to light and rapidly even in its absence. Mellor 2, Supp. l: 550 (1956). See also ALCOHOLS plus Hypochlorous Acid.

LANTHANUM La Phosphorus See CERIUM plus Phosphorus. 599

REVISIONS TO NFPA NO. 491M 491M-81

LANTHANUM OXIDE La20a Chlorine Triflfforide See CHLORINE TR1FLUORIDE Plus Ar- senic Trioxide.

LANTHANUM PHOSPHIDE LaP Water See CEROUS PHOSPHIDE plus Water.

LEAD Pb Chlorine Trifluoride See ALUMINUM plus Chlorine Trifluoride. Sodium Azide See SODIUM AZIDE plus Copper. Sodium Carbide See MERCURY plus Sodium Carbide.

LEAD ACETATE (CH3COO)~Pb Potassium Bromate See POTASSIUM BROMATE plus Lead Acetate.

LEAD AZIDE Pb(Na)2 (self-reactive) Lead ,~zide decomposes at 250 ° C. It is explosively trustable. Mellor 8, Supp. 2:43 (1967). See also SODIUM AZIDE plus Copper.

LEAD CHLORATE Pb(CI03)3 Sulfur See SULFUR plus Lead Chlorate.

LEAD CHLORITE Pb (C102)~ (self-reactive) Lead chlorite has detonator properties but its behavior is somewhat unpredictable. MeUor 2, Supp. l: 574 (1956).

LEAD DIOXIDE PbO~ Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Alu- minum Oxide. Hydrogen Peroxide Hydrogen peroxide reacts violeutly with lead dioxide, lead monoxide, mercuric oxide, potassium, and sodium. Mellor 1:937 (1946-1947). Performic Acid See PERFORMIC ACID plus Lead Dioxide.

LEAD FLUORIDE PbF~ Fluorine See FLUORINE plus Lead Fluoride.

LEAD HYPOPHOSPHITE Pb(PH~O~)2 Lead Nitrate This mixture forms a highly explosive double salt with rate of detonation greater than that of mercury fuhninate. Mellor 8:887 (1946-1947). 600 491M-82 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

(self-reactive) Lead hypophosphite forms impact-sensitive ammunition-priming mixtures. MeUor 8, Supp. 3:623 (1971).

LEAD MONOXIDE PbO Hydrogen Peroxide See LEAD DIOXIDE plus Hydrogen Per- oxide.

LEAD NITRATE Pb(NO3)~ Ammonium See AMMONIUM THIOCYANATE plus Thiocyanate Lead Nitrate. Lead Hypophosphite See LEAD HYPOPHOSPHITE plus Lead Nitrate.

LEAD OXYCHLORIDE Pb2OC12 Potassium See POTASSIUM plus Boric Acid.

LEAD PEROXIDE Pb02 Potassium See POTASSIUM plus Boric Acid.

LEAD STYPHNATE (self-reactive) This compound is a weak but highly sensitive explosive. Urbanski, Vol. III, p. 213 (1967). An employee was removing a beaker of lead styphnate from a laboratory oven when he apparently bumped the beaker on the side of the oven. A detonation occurred. MCA Case History 987 (1966). Three kilograms of lead styphnate detonated from an unknown cause in the anteroom of a dry-house. Wet material in two adjacent drying rooms did not detonate. Chem. Abst. 26:5210 (1932).

LEAD SULFATE PbS04 Potassium See POTASSIUM plus Boric Acid.

LEAD SULFIDE PbS Iodine Monochloride See IODINE MONOCHLORIDE plus Cad- mium Sulfide. Hydrogen Peroxide See ANTIMONY TRISULFIDE plus Hydro- gen Peroxide. 601 REVISIONS TO NFPA NO. 491M 491M-83

LEAD TETRAAZIDE Pb(N3)4 (self-reactive) Lead tetraazide is too uustable to be isolated. The ammonium double salt is an unstable explosive compound. Mellor 8, Supp. 2:22 (1967).

LEAD TRINITRORESORCINATE (See LEAD STYPHNATE.)

LEWIS-TYPE CATALYSTS Allyl Chloride See SULFURIC ACID plus Allyl Chloride.

LINSEED OIL Chlorine See CHLORINE plus Polypropylene.

LITHIUM Li Arsenic The reaction of lithium is violent with both strongly heated arsenic and phosphorus. Mellor 2, Supp. 1:77 (1956). Beryllium See LITHIUM plus Vanadium. Bromoform Lithium mixed with the following compounds can explode on impact: bromoform, carbon tetrabromide, chloroform, iodoform, methyl dichloride, and methyl diiodide. Mellor 2, Supp. 2:83 (1961). Carbides Molten lithium attacks carbides and silicates. MeUor 2, Supp. 2:84 (1961). Carbon Dioxide See also LITHIUM Plus Water. Carbon Monoxide The product of the reaction between lithium and Water and carbon monoxide, lithium carbonyl, detonates violently with water, igniting gaseous products. MeUor 2, Supp. 2:88 (1961). Carbon Tetrabromide See LITHIUM plus Bromoform. Carbon Tctrachloride A billet-cutting knife initiated a violently explosive reaction between lithium and carbon tetraehloride. Mellor 2, Supp. 2: (1961). See also LITHIUM plus Water. Chlorine See CESIUM plus Chlorinc. Chloroform See LITHIUM plus Bromoform. Chromic Oxide The reaction of lithium and chromic oxide occurs around 180° C with consequent temperature rise to 965 ° C. MeUor 2, Supp. 2:81 (1961). Chronfium See LITHIUM plus Vanadium. 602 / 491M-84 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

Cobalt Alloys Molten lithium attacks the following alloys: cobalt alloys, iron alloys, manganese alloys, nickel alloys. Mellor 2, Supp. 2:80 (1961). Ferrous Sulfide The reaction of lithimn and ferrous sulfide occurs around 260 ° C with consequent temperature rise to 945 ° C. Mellor 2, Supp. 2:82 (1961). Hydrogen Lithium burns in gaseous hydrogen. Mellor 1:327 (1946-1947). Iodine See IODINE plus Lithium. Iodoform See LITHIUM plus Bromoform. Iron Alloys See LITHIUM plus Cobalt Alloys. Manganese Alloys See LITHIUM plus Cobalt Alloys. Methyl Dichloride See LITHIUM plus Bromoform. Methyl Diiodide See LITHIUM plus Bromoform. Molybdenum Trioxide The reaction of lithium and molybdenum trioxide occurs at about 180°C with consequent temperature rise to 1400 ° C. MeUor 2, Supp. 2:82 (1961). Nickel Alloys See LITHIUM plus Cobalt Alloys. Niobium Pentoxide The reaction of lithium and niobium pentoxide occurs around 320° C, with consequent temperature rise to 490 ° C. MeUor 2, Supp. 2:81 (1961). Nitrogen The reaction of lithium and nitrogen increases greatly as the metal melts. Mellor 2, Supp. 2:77 (1961). Organic Matter Molten lithium attacks plastics and rubber. Mellor 2, Supp. 2:84 (1961). Phosphorus See LITHIUM plus Arsenic. See PHOSPHORUS plus Cesium. Rubber See LITHIUM plus Organic Matter. Silicates See LITHIUM plus Carbides. Sodium Nitrite Lithium reacts with sodium nitrite to form lithium sodium hydronitrite, a compound which decomposes violently around 100°- 130° C. Mellor 2, Supp. 2:78 (1961). Sulfur The reaction of lithium and sulfur is very violent when either is molten, starting with explosive violence. Mellor 2, Supp. 2:74 (1961). Tantalum Pentoxide The reaction of lithium and tantalum pentoxide occurs around 410°C with consequent temperature rise to 595 ° C. Mellor 2, Supp. 2:81 (1961). 603 REVISIONS TO NFPA NO. 491M 491M-85 Lithium (co nt.) Titanium Dioxide The reaction of lithium and titanium dioxide occurs around 200°C with a flash of light; the temperature can reach 900° C. Mellor 2, Supp. 2:81 (1961). Tungsten Trioxide The reaction of lithium aud tu.ugsten trioxide occurs at about 200°C with consequent temperature rise to 1030° C. MeUor 2, Supp. 2:82 (1961). Vanadium Molten lithium at 180°C attacks vanadium, beryllium, or chromium severely. Mellor 2, Supp. 2:80 (1961). Vanadium Pentoxide The reaction of lithium and vanadium pentoxide occurs around 400 ° C; the temperature then rises rapidly to 768° C. Mellor 2, Supp. 2:81 (1961). Water Liquid lithium is readily ignited and reacts with most extinguishing agents, including water, carbon tctrachloride and carbon dioxide. Mellor 2, Supp. 2:71 (1961).

LITHIUM ALUMINUM HYDRIDE LiAIH4 Alcohols See LITHIUM ALUMINUM HYDRIDE plus Water. Acids See LITHIUM ALUMINUM HYDRIDE plus Water. Benzoyl Peroxide See BENZOYL PEROXIDE plus Lithium Aluminum Hydride. 2-Chloromethylfuran See 2-CHLOROMETHYLFURAN plus Lith- and Ethyl Acetate ium Aluminum Hydride and Ethyl Acetate. "Dimethyl Ether Use of lithium aluminum hydride to dry methyl ethers may cause explosions, which are attributed to solubility of carbon dioxide. High concentrations of peroxides were found to be present. MCA Guide for Safety, Appendix 3 (1972). Methyl Ethyl Ether See LITHIUM ALUMINUM HYDRIDE plus Dimethyl Ether. Perfluorosuccinamide Perfluorosuccinamide was added to an ether solution of lithium aluminum hydride in a nitrogen atmosphere. Hydrolysis was then attempted but as the second drop of water was added, a violent explosion occurred. MCA Guide for Safety, Appendix 3 (1972). Tetrahydrofuran See TETRAHYDROFURAN plus Lithium Aluminum Hydride. 604 491M-86 REPORT OF COMMITTEE ON CHEMICALSAND EXPLOSIVES

Water Lithium aluminum hydride reacts vigorously with hydroxy compounds: water, alcohols, carboxylic acids. Mellor 2, Supp. 2:142 (1961).

LITHIUM CARBIDE Li2C~ Iodine See IODINE plus Cesium Carbide. Selenium See SULFUR plus Lithium Carbide. Sulfur See SULFUR plus Lithium Carbide.

LITHIUM CARBONYL LiCO (self-reactive) See LITHIUM plus Carbon Monoxide and Water.

LITHIUM CHLORIDE LiC1 Bromine Trifluoride See BROMINE TRIFLUORIDE plus Barium Chloride.

LITHIUM HYDRIDE LiH Nitrous Oxide See NITROUS OXIDE plus Lithium Hydride.

LITHIUM METHYL (See METHYL-LITHIUM.)

LITHIUM PHENYLAZOXIDE Li0N:NCsH5 (self-reactive) See PHENYL-LITHIUM plus Nitrous Oxide.

LITHIUM SODIUM HYDRONITRITE (See LITHIUM plus Sodium Nitrite.)

LITHIUM TETRAAZIDOBORATE LiB(N3)4 (self-reactive) See BORON TRIAZIDE (self-reactive).

MAGNESIUM Mg Bromobenzyl Bromobenzyl trifluoride was added to mag- Trifluoride nesium turnings in sodium-dried ether at a rate so as to maintain reflux. After a period of time an explosion occurred. MCA Case History 1834 (1972). Chlorinc Trifluoride See ALUMINUM plus Chlorine Trifluoride. Nitric Acid A mixture of finely divided magnesium and nitric acid is explosive. Pieters, p. 28 (1957). Performi~ Acid Powdered magnesium can decompose performic acid violently. Berichte 48:1139 (1915). 605 REVISIONS TO NFPA NO. 491M 491M-87

MAGNESIUM CHLORIDE MgCI 2-Furan Percarboxylic See 2-FURAN PERCARBOXYLIC ACID Acid (self-reactive).

MAGNESIUM HYPOPHOSPHITE Mg(PH202)2 (self-reactive) Magnesium hypophosphite liberates spontaneously flammable phosphine when heated. Mellor 8:885 (1946-1947).

MAGNESIUM NITRATE Mg(N03)2 Dimethyl Formamide See DIMETHYL FORMAM1DE plus Mag- nesium Nitrate.

MAGNESIUM OXIDE MgO Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Alu- minum Oxide.

MAGNESIUM PERCHLORATE Mg(Cl04)2 Ammonia Magnesium perchlorate was contained in a small steel refrigeration-type drying tube and the ammonia was passed through it (after the system was evacuated) in small increments in an attempt to further desiccate it. It was noted that the outside of the drying tube was warm to the touch. Shortly thereafter the tube exploded violently. F. F. Chapman (1973). Hydrocarbons Magnesium perchlorate, used in drying unsaturated hydrocarbons, exploded oll being heated to 220 ° C. P. M. Heertjes and J. P. W. Houtman, Chem. Weekblad 38:85 (1941).

MANGANESE ALLOYS Lithium See LITHIUM plus Cobalt Alloys.

MANGANESE DIOXIDE Mn02 Chlorine Trifluoride See also CHLORINE TRIFLUORIDE plus Aluminum Oxide. Sodium Peroxide See SODIUM PEROXIDE Plus M'mganese Dioxide.

MANGANESE HEPTOXIDE Mn207 (self-reactive) See also POTASSIUM PERMANGANATE plus Sulfuric Acid. 606 491M-88 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

MANGANOUS BROMIDE MnBr2 Potassium See POTASSIUM plus Ammonium Bromide.

MANGANOUS CHLORIDE MnC12 Potassium See POTASSIUM plus Aluminum Bromide. Sodium See SODIUM plus Ferrous Chloride.

MANGANOUS HYPOPHOSPHITE Mn(PH.~02)2 (self-reactive) Manganous hypophosphite detonates above 200 ° C. Mellor 8:889 (1946-1947).

MANGANOUS IODATE Mn(I03)3 Bromine Trifluoride See BROMINE TRIFLUORIDE plus Bis- muth Pentoxide.

MANGANOUS IODIDE Mni~ Potassium See POTASSIUM plus Ammonium Bromide.

MANGANOUS OXIDE MnO Fluorine See FLUORINE plus Trimanganese Tetroxide.

MERCAPTANS RSH Calcium Hypochlorite See CALCIUM HYPOCHLORITE plus Mer- captans.

MERCURIC AZIDE Mg(N3)~ (self-reactive) Mercuric azide decomposes at 190 ° C. It is explosively unstable. Mellor 8, Supp. 2:43 (1967).

MERCURIC BROMIDE HgBr2 Sodium See SODIUM plus Ferrous Chloride. Potassium See POTASSIUM plus Aluminum Bromide.

MERCURIC CHLORIDE HgCl.o Potassium See POTASSIUM plus Aluminum Bromide. Sodium See SODIUM plus Ferrous Chloride.

MERCURIC CHLORITE Hg(CIO~)~ (self-reactive) Mercuric chlorite.is an explosive s~tlt. MeUor 2, Supp. 1:575 (1956).

MERCURIC CYANIDE Hg (CN)2 Fluorine See FLUORINE plus Mercuric Cyanide. 607 REVISIONS TO NFPA NO. 49lM 491M-89

MERCURIC CYANIDE OXIDE Hg2(CN)=O (self-reactive) Several instances are cited where explosions have occm'red in handling or manipulating this substance. Rubbing the material is a frequent cause of the explosions. Chem. Abst. 16:2010 (1972). Chem. Abst. 11:300 (1917).

MERCURIC FLUORIDE HgF2 Potassium See POTASSIUM plus Aluminum Bromide. Sodium See SODIUM plus Ferrous Chloride.

MERCURIC IODIDE HgI2 Chlorine Trifluoride See CHLORINE TRIFLUO~RIDE plus Mer- curic Iodide. Potassium See POTASSIUM plus Aluminum Bromide. Sodium See SODIUM Plus Ferrous Chloride.

MERCURIC NITRATE Hg(NOa)2 Hypophosphoric Acid Mercuric nitrate is violently reduced to mercury by hypophosphoric.acid. Mellor 4:993 (1946-1947).

MERCURIC OXIDE HgO Chlorine See CHLORINE plus Mercuric Oxide. Hydrogen Peroxide See LEAD DIOXIDE plus Hydrogen Peroxide.

MERCURIC SULFATE HgSO4 Hydrogen Chloride Absorption of gaseous hydrogen chloride on mercuric sulfate becomes violent at 125 ° C. MeUor 2, Supp. 1:462 (1956).

MERCUROUS AZIDE MgNa (self-reactive) Mercurous azide decomposes at 210 ° C. It is explosively unstable. Mellor 8, Supp. 2:43 (1967).

MERCUROUS CHLORIDE HgCl Potassium See POTASSIUM plus Ahuninum 13,romide. Sodium See SODIUM plus Ferrous Chloride.

MERCUROUS HYPOPHOSPHATE Hg4P206 (self-reactive) Mercurous hypophosplmtc decomposes explosively. Mellor 8, Supp. 3:651 (1971). 608 491M-90 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

MERCUROUS NITRATE HgN03 Carbon See CARBON plus Mercurous Nitrate.

MERCURY Hg Chlorine Flame forms with chlorine jet over mercury surface at 200 ° -300 ° C. Mellor 2, Supp. 1:381 (1956). Sodium Carbide Ground mixtures of sodium carbide and mercury, aluminum, lead, or iron can react vigorously. MeUor 5:848 (1946-1947). MERCURY SALTS Nitromethane See COPPER SALTS plus Nitromethane.

MESITYL OXIDE (CH3)~C :CHCOCH3 2-Aminoethanol Mixing mesityloxide and 2-aminoethanol in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under corn- , plete reference. Chlorosulfonic Acid Mixing mesityl oxide and chlorosulfonic acid hi a closed contahmr caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Ethylene Diamine Mixing mesityl oxide and ethylene diamine in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Nitric Acid Mixing mesityl oxide and nitric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Notc under complete reference. Oleum Mixing mesityl oxide and oleum in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note.under complete reference. Sulfuric Acid Mixing mesityl oxide and 96% sulfuric ackl in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. 609 REVISIONS TO NFPA NO. 491M 491M-91

METALLIC HALIDES Bromine Pentafluoride See BROMINE PENTAFLUORIDE plus Metal Oxides.

METAL OXIDES Bromine Pentafluoride See BROMINE PENTAFLUORIDE plus Metal Oxides. Performic Acid Metal oxides catalyze the decomposition of performic acid, resulting in aa explosion. Grignard 11:179 (1935-1954).

METALS Bromine Pentafluoride Very violent reactions may occur between bromine pentafluoride and powdered or warmed metals. MeUor 2, Supp. 1:172 (1956). Bromirie Trifluoride Halogen fluorides appear to react with all metals. The reaction is vigorous when no film forms. Mellor 2, Supp. 1:163 (1956). Performic Acid Metals catalyze the decomposition of performic acid and can make it explosive. Grignard 11:179 (1935-1954).

METHANE CH4 Bromine See BROMINE PENTAFLUORIDE plus Pentafluoride Acetic Acid. Chlorine See CHLORINE plus Methane. Chlorine Dioxide See CHLORINE DIOXIDE plus Butadiene. Oxygen Difluoride See HYDROGEN plus Oxygen Difluoride.

METHANOL CH30H Phosphorus Trioxide See DIMETHYL FORMAMIDE plus Phos- phorus.

3-METHOXY-4-HYDROXY BENZALDEHYDE CH30(HO) C6H~CHO (See VANILLIN.) Bromine See BROMINE plus Methyl Alcohol. Perchloric Acid See PERCHLORIC ACID plus Ethyl Alcohol. Potassium Tert.- See ACETONE plus Potassium Tert.-Butoxide. Butoxide Tetrachlorobenzene See SODIUM HYDROXIDE plus Tetra- and Sodium chlorobenzene and Methyl Alcohol. Hydroxide 610 491M-92 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

METHYL AZIDE CHsN3 Dimethyl Malonate A serious explosion occurred in the con- and Sodium densation of ,nethyl azide with dimethyl Methylate malonate in the presence of sodium methylate. Ch. Grundmann and H. Haklcnwanger, Angew Chem. 62A: 410 (1950).

METHYL 2-AZIDOBENZOATE CH3OCO.C6H4-2-NNN (self-reactive) During distillation of this material the apparatus exploded. Wischmeyer (1972).

METHYL BROMIDE CH~Br Dimethyl Sulfoxide A reaction between methyl bromide and dimethyl sulfoxide resulted in an explosion that shattered the apparatus. Searos and Sera~skas (1973).

2-METHYL-3-CHLOROFURAN OCCH3:CCICH:CH (self-reactive) I I A small sample (20 milliliters) had been made, distilled and allowed to stand over the weekend. During the weekend it exploded. MCA Guide for Safety, Appendix 3 (1972). Lithium Aluminum A mixture of chlorinated orga~fic compounds Hydride and Ethyl consisting principally of 2-METHYL-3- Acetate CHLOROFURAN was subjected to reductive dechlorination, with lithiunl aluminum hydride after which ethyl acetate was added in small increments to decompose excess lithium aluminum hydride. After a few drops had been added, a violent explosion occurred. Chem. d" Ind. 14:432 (1957).

METHYL DICHLORIDE CHIC12 Lithium See LITHIUM plus Bromoform. Sodium-Potassium See SODIUM-POTASSIUM ALLOY plus Alloy Methyl Dichloride.

5-METHYL-2, 4-DIETHYNYLPHENOL (CHi C-),zC6H2(OH)CH3 (self-reactive) This compound is unstable in light and air. Chem. Abst. 75:19831 (1971).

"METHYL DIIODIDE CH~I2 Lithium See LITHIUM plus Bromoform. 611 REVISIONS TO NFPA NO. 491M 491M-93

METHYLENE CHLORIDE C1CH2CI N-Methyl-N-Nitroso See N-METHYL-N-NITROSO UREA plus Urea and Potassium Hydroxide and Methylene Chloride. Potassium Hydroxide Potassium Tert.- See ACETONE plus Potassium Tert.-Butoxide. Butoxide

METHYLENE DIISOCYANATE OCN-CH:-NCO Dimethyl Formamide See DIMETHYL FORMAMIDE plus Methy- lene Diisocyanate.

METHYL ETHYL ETHER CH3OC~H5 Lithium Aluminum See IJ-THIUM ALUMINUM HYDRIDE Hydride plus Dimethyl Ether.

METHYL ETHYL KETONE CH3COC~H5 ChlorosulfonicAcid Mixing methyl ethyl ketone and chlorosulfonic acid in a closed container caused the temperature and pressure to increase. Flynn andRossow (1970). See Note under complete reference.

Oleum Mixing methyl ethyl ketone and oleum in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Potassium Tert.- See ACETONE plus Potassium Tert.-Butoxide. Butoxide

2- METHYL-5-ETHYLPYRIDINE N :C(CH3)CH :CHC(C2Hb) :CH Nitric Acid See NITRIC ACID plus 2-Methyl-5-Ethyl- pyridine.

METHYL HYPOCHLORITE CH~OCI (self-reactive) Methyl hypochlorite decomposes explosively when exposed to light and rapidly even in its absence. Mellor 2, Supp. 1:550 (1956). See also ALCOHOLS plus Hypochlorus Acid.

METHYL ISOBUTYL KETONE CH3COCH2CH(CH~)2 Potassium Tert.- See ACETONE plus Potassium Tert.-Butoxide. Butoxide 612 491M-94 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

METHYL LITHIUM CH3Li Air Mellor 2, Supp. 2:91 (1961).

MOLYBDENUM Mo Bromine Trifluoride Powdered molybdelmm, powdered titanium, and powdered vanadium all react with bromine trifluoride, producing incandescence. Mellor 2, Supp. l: 164 (1956). Reaction between molybdenum or tungsten and bromine trifluoride is vigorous. No protective film forms with the volatile hexafluoride of the metal. Mellor 2, Supp. 1:163 (1956). Chlorine Trifluoride Mellor 2, Supp. 1:156 (1956).

MOLYBDENUM DISULFIDE MoS, Hydrogen Peroxide See ANTIMONY TRISULFIDE plus Hydro- gen Peroxide.

MOLYBDENUM TRIOXIDE MoOn Chlorine Trifluoride See also CHLORINE TRIFLUORIDE plus Aluminum Oxide. Lithium See LITHIUM plus Molybdenum Trioxide.

MONOAMMONIUM PHOSPHATE NH4H2PO~ Sodium See SODIUM plus Monoammonium Phos- phate.

MONOETHANOLAMINE NH2CH2CH20H See 2-AMINOETHANOL

N- CHLOROETHYLENEIMINE CI.NCH~CH~ I__l (self-reactive) M C A Guide .for Safety, Appendix 3 (1972).

NEODYMIUM Nd Nitrogen Neodymium and nitrogen rcact vigorously. MeUor 8, Supp. 1:164 (1964). Phosphorus Neodymium and phosphorus react vigorously at 400 ° -- 500 ° C. Mellor 8, Supp. 3:347 (1971).

NEODYMIUM PHOSPHIDE NdP Nitric Acid Neodymium phosphide and nitric acid react violently. MeUor 8, Supp. 3:348 (1971). Water See CEROUS PHOSPHIDE plus Water. 613 REVISIONS TO NFPA NO. 49]M 491M-95

NICKEL Ni Hydrazine The catalytic decomposition of hydrazine in the presence of Raney nickel may be vigorous at room temperature. MeUor 8, Supp. 2:83 (1967). Hydrazoic Acid Raney nickel and hydrazoic acid undergo a vigorous decomposition. Mellor 8, Supp. 2:4 (1967). PerformicAeid Powdered nickel can decompose performic acid violently. Berichte 48:1139 (1915). Phosphorus See COPPER plus Phosphorus.

NICKEL ALLOYS Lithium See LITHIUM plus Cobalt Alloys.

NICKEL BROMIDE NiBr2 Potassium See POTASSIUM plus Aluminum Bromide.

NICKEL CHLORIDE NiC12 Potassium See POTASSIUM plus Aluminum Bromide.

NICKEL CHLORITE Ni(CIO2)2 (self-reactive) The dihydrate of nickel chlorite explodes when heated to 100° C. MeUor 2, Supp. 1:574 (1956).

NICKEL FLUORIDE NiF2 Potassium See POTASSIUM plus Ammonium Bromide.

NICKEL HYPOPHOSPHITE Ni(PH202)~ (self-reactive) Nickel hypophosphite liberates spontaneously flammable phosphine above 100°C. MeUor 8:890 (1946-1947).

NICKEL IODIDE NiI2 Potassium See POTASSIUM plus Aluminum Bromide.

NICKEL NITRIDE NiaN Acids The reaction of nickel nitride and acids may be explosive with high acid concentrations and heat. Mellor 8, Supp. 1:238 (1964). 614 491M-96 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

NIOBIUM Nb Bromine Trifluoride Niobium and tantalum each reacts with bromine trifluoride with incandescence. Mellor 2, Supp. 1:164 (1956). Chlorine Powdered niobium reacts energetically with chlorine. Mellor 2, Supp. l: 381 (1956).

NIOBIUM PENTOXIDE Nb.205 Bromine Trifluoridc See BROMINE TIIIFLUORIDE plus Bis- muth Pentoxide. Lithium See LITHIUM plus Niobium Pentoxide.

NITRIC ACID HN03 Acetic Anhydride See ACETIC ANHYDRIDE plus Nitric Acid. Experiments demonstrate that mixtures containing more than 50% by weight of nitric acid in acetic anhydride may act as detonating explosives under certain conditions. An indication is given of the percentage mixtures of acetic anhydride-nitric acid which could be detonated using a priming charge and detonator. BCISC 42 (166): 2 (1971). Acetylene Concentrated nitric acid on acetylene gives trinitromethane, which melts at 15°C and is explosive in the liqukt state. Kirk and Othmer 9:430-2 (1947). Acrolein See ACROLEIN plus Nitric Acid. Allyl Alcohol See ALL~fL ALCOHOL plus Nitric Acid. Allyl Chloride See ALLYL CHLORIDE plus Nitric Acid. 2-Aminoethanol See 2-AMINOETHANOL plus Nitric Acid. Ammonia See NITRIC ACID plus Diborane. Ammottium Hydroxide Mixing 70% nitric acid and 28% ammo!fium hydroxide in a closed container c~msed the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Mellor 8, Supp. 1:349 (1964). Aniline See also NITRIC ACID plus l)iborane. Antimony See ANTIMONY plus Nitric Acid. Bromine Pentafluoride See BROMINE PENTAFLUORIDE plus Nitric Acid. n-Butyraldehyde See n-BUTYRALDEHYDE plus Nitric Acid. Calcium See- CALCIUM HYPOPHOSPHITE plus Hypophosphite Nitric Acid. Carbon See CARBON plus Nitric Acid. 615 REVISIONS TO NFPA NO. 491M 491M-97

Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Nitric Acid. Chlorosulfonic Acid See CHLOROSULFONIC ACID plus Nitric Acid. Cresol See CRESOL plus Nitric Acid. Cumene See CUMENE plus Nitric Acid. Cuprous Nitride See CUPROUS NITRIDE plus Sulfuric Acid. Cyclohexanol Cyclohexanol and nitric acid can react at room temperature to form "~ violently explosive material. Chem. & Ind. 1971: (19) (1971). Diborane Mixtures of fuming nitric acid and any of the follo wing are self-igniti ng: d ibonu m, anili ue, terpenes, furfuryl alcohol, and ammonia. Mellor 8, Supp. 2:341 (1967). Diisopropyl Ether See DIISOPROPYL ETHER plus Nitric Acid. Epichlorohydrin See EPICHLOROHYDRIN plus Nitric Acid. Ethylene Diamine See ETHYLENE DIAM1NE plus Nitric Acid. Ethyleneimine See ETHYLENEIMINE plus Nitric Acid. Fluorine Scc FLUORINE plus Nitric Acid. Furfuryl Alcohol Furfuryl alcohol is ignited immediately by concentrated nitric ~cid. MCA Case History 193 (1952). See also NITRIC ACID plus Diborane. Glyoxal Mixing 70% nitric acid and glyoxal in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete ~'cference. Hydrazine See HYDRAZINE plus Nitric Acid. Hydrazoic Acid See HYDRAZOIC ACID plus Nitric Acid. Hydrogen Peroxide" See HYDROGEN PEROXIDE plus Nitric Acid. Hydrogen Telluride Cold fuming nitric acid ignites hydrogen telluride, sometimes explosively. Pascal 10:505 0931-1934). Indane and Sulfuric See INDANE plus Nitric Acid and Sulfuric Acid Acid. Isoprene See ISOPRENE plus Nitric Acid. Maguesium See MAGNESIUM plus Nitric Acid. Mesityl Oxide See MESITYL OXIDE plus Nitric Acid. 2-Methyl-5- Chem. Eng. News 51 (34) 142 (1973). Ethylpyridine Neodymium See NEODYMIUM PHOSPHIDE plus Nitric Phosphide Acid. Oleum See OLEUM plus Nitric Acid. 616 491M-98 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES Nitric Acid (cont.) Phthalic Acid See PHTHALIC ANHYDRIDE plus Nitric Acid. Phthalic Anhydride See PHTHALIC ANHYDRIDE plus Nitric Acid. Propiolactone (BETA-) See PROPIOLACTONE (BETA-) plus Nitric Acid. Propylene Oxide See PROPYLENE OXIDE plus Nitric Acid. Pyridine See PYRIDINE plus Nitric Acid. Selenium See SELENIUM IODOPHOSPHIDE plus Iodophosphide Nitric Acid. Sodium Azide See SODIUM AZIDE plus Nitric Acid. Sodium Hydroxide See SODIUM HYDROXIDE plus Nitric Acid. Sulfamic Acid See SULFAMIC ACID plus Nitric Acid. Sulfuric Acid and Sulfuric acid, nitric acid and fat were placed in Glycerides a tightly closed container. Within 10 minutes, the container exploded. Chem. Eng. News 51 (31): 32 (1973). Terpenes See NITRIC ACID plus Diborane, Tetraboron See TETRABORON DECAHY,DRIDE plus Decahydride Nitric Acid. Triazine Nitrolysis of triazine with 99% nitric acid in a trifluoroacetic anhydride solvent caused a violent explosion at 36 ° C. Rolston (1972). Vinyl Acetate See VINYL ACETATE plus Nitric Acid. Vinylidene Chloride See VINYLIDENE CHLORIDE plus Nitric Acid.

NITRIC OXIDE NO Aluminum See ALUMINUM pins Carbon Disulfide. Carbon Disulfide These compounds react explosively with emis- sion of light. Mellor 8, Supp. 2:232 (1967). Ozone See OZONE plus Nitric Oxide. Phosphorus See PHOSPHORUS plus Nitric Oxide. Rubidium Carbide See RUBIDIUM CARBIDE plus Sulfur Dioxide. Sodium Monoxide See SODIUM MONOXIDE plus Nitric Oxide. Unsymmetrical This mixture ignites on sparking. Dimethylhydrazine MeUor 8, Supp. 2:234 (1967).

NITROAROMATIC COMPOUNDS Chlorinc Trifluoride Solutions of nitroaromatic compounds in chlorine trifluoride are extremely sensitive to shock. Mellor 2, Supp. 1:156 (1956). 617 REVISIONS TO NFPA NO. 49[M 491M-99

NITROBENZENE C6HsNO2 Nitrogeu Tetroxide See NITROGEN TETROXIDE plus Nitro- benzene. Silver Perchlorate See SILVER PERCHLORATE plus Acetic Acid. NITROGEN N~ Lithium See LITHIUM plus Nitrogen. Neodymium See NEODYMIUM plus Nitrogen.

NITROGEN DIOXIDE No2 Cyclohexane See CYCLOHEXANE plus Nitrogen Dioxide. Fluorine See FLUORINE plus Nitrogen Dioxide. Formaldehyde See FORMALDEHYDE plus Nitrogen Di- oxide. NITROGEN IODIDE NI3 Ozone Set OZONE plus Nitrogen Iodide.

NITROGEN IODIDES (self-reactive) See IODINE plus Ammonium Hydroxide.

NITROGEN PEROXIDE NO2 (See also NITROGEN TETROXIDE.) Aluminum See ALUMINUM plus Carbon Disulfide. Ammolfia See NITRIC OXIDE plus Ammonia. Boron Trichloride See BORON TRICHLORIDE plus Nitrogen Peroxide. Sodium See SODIUM plus Nitrogen Peroxide.

NITROGEN TETROXIDE N~04 Alcohols An explosion of these materials killed a research worker in a 1955 accident. MeUor 8, Supp. 2:264 (1967). Nitrobenzcue Mixtures of nitrogen tetroxide and nitrobenzene qualify as military explosives. Mellor 8, Supp. 2:264 (1967). Petroleum An explosion of these materials killed 17 workers and devastated a plant in Bodio, Switzerla,nd. Mellor 8, Supp. 2:264 (1967). See NITROGEN TETROXIDE plus Fuels. See NITROGEN TETROXIDE plus Orgalfie Matter. Toluene A mixture of these chemicals caused an explosion at an industrial plant in Zschornewitz. MeUor 8, Supp. 2:264 (1967). 618 491M-I00 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

NITROGEN TRICHLORIDE NCI3 Ozone See OZONE plus Nitrogen Trichloride.

NITROGEN TRIFLUORIDE NF3 Tetrafluorohydrazine Several hundred grams of a crude reaction mixture involving nitrogen trifluoride and tetrafluorohydrazine had been collected in a small stainless steel cylinder, l)uring opening of valves to measure cylinder pressure, the cylinder exploded, killing one man and in- juring another. MCA Case History 683 (1966). NITROGLYCERIN C3H~(ONO~)3 Ozone See OZONE plus Nitroglycerin.

NITROMETHANE O~NCH3 Hexamethylbenzene See HEXAMETHYLBENZENE plus Nitro- methane. o-NITROPHENOL HO-C6H4-2-N02 Potassium Hydroxide See POTASSIUM HYDROXIDE plus o- Nitrophenol.

2-NITROPROPANE CH3CHNO~CH3 Chlorosulfo,lie Acid See CHLOROSULFONIC ACID plus 2- Nitropropane. Oleum See OLEUM pltLs 2-Nitropropane.

N-NITROSOMETHYLUREA ONN(CHa)CO.NH2 Potassium Hydroxide See N-METHYL-N-NITROSO UREA plus and Methylene Potassium Hydroxide and Methylene Chloride. Chloride. NITROSYL AZIDE NON~ (self-reactive) This unstable yellow compound decomposes even at minus 50 ° C. MeUor 8, Supp. 2:22 (1967). NITROSYL CHLORIDE NOCI Aluminum See ALUMINUM plus Nitrosyl Cldoride.

NITROSYL PERCHLORATE NO.CIO. (self-reactive) Decomposition of ~fitro~yl perehlorate begins just below 100 ° C. Above 100 ° C (115-120 ° C) a low order explosion occurs. H. Gerding and W. F. Haak, Chem. Weekblad 52:282-3 (1956). 619 REVISIONS TO NFPA NO. 4911V[ 491M-101

Metal Salts The hot reaction of nitrosyl perchlorate with metal salts, which is a way to prepsre per- chorates, forms salts that are very explosive. Kirk and Othmer, Second Ed. 5:69 (1963).

NITROS YLSULFURIC ACID 0 :NOSO:OH Dinitroanilinc An explosion occurred during the diazotization Hydrochloride using nitrosylsulfuric acid which resulted in several fatalities. Subsequent tests have shown that this was due to the high concentration of reactants in the mixture. MCA Case History 1763 (1971).

NITROUS OXIDE N20 (self-reactive) This compound decomposes explosively at high temperatures. Mellor 8, Supp. 2" 207 (1967). Aluminum See ALUMINUM plus Carbon Disulfide. Hydrazine See NITROUS OXIDE plus Lithium Hydride. Lithium Hydride Spontaueous ignition occurs when nitrous oxide and lithium hydride or hydrazine are mixed. Mellor 8, Supp. 2:214 (1967). Phelw1-Lithium See PHENYL-LITHIUM plus Nitrous Oxide. Sodium See SODIUM plus Nitrogen Peroxide. / / NITRYL CHLORIDE NO2CI Ammonia Mellor 8, Supp. 1:331 (1964).

NITRYL FLUORIDE NO~F Phosphorus See PHOSPHORUS plus Nitryl Fluoride. Potassium See POTASSIUM plus Nitryl Fluoride.

N, N-DICHLOROMETHYLAMINE CH3NC12 Sodium Sulfide N, N-dichloromethylamine exploded violently on addition of sodium sulfide. Biul. Wojskowej Akad. Tech. 8 (.48): 75-9 (1959).

N, N-DIMETHYLANILINE C~HsN(CH3)2 Benzoyl Peroxide See BENZOYL PEROXIDE plus N, N-Di- methylaniline. 620 401M-102 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

N-METHYL-N-NITROSO UREA ON-N(CHa)CO.NH~ Potassium Hydroxide Diazomethane was being prepared by portion- and Methylene wise addition,s of N-methyl-N-nitroso urea to Chloride a flask containing 40% potassium hydroxide and methylene chloride. At the fourth addition a loud detonation occurred. MCA Guide for Safety, p. 301 (1972).

OLEUM H2S0~.S03 Acetic Acid See ACETIC ACID plus Oleum. Acetic Anhydride See ACETIC ANHYDRIDE plus Oleum. Acetonitrilc See ACETONITRILE plus Oleum. Acrolein See ACROLEIN plus Oleum. Acrylic Acid See ACRYLIC ACID plus Oleum. Acrylonitrile See ACRYLONITRILE plus Oleum. Allyl Alcohol See ALLYL ALCOHOL plus Oleum. Allyl Chloride See ALLYL CHLORIDE plus Oleum. 2-Aminoethanol See 2-AMINOETHANOL plus Oleum. Ammonium Hydroxide Mixing oleum and 28% ammonium hydroxide in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under Com- plete reference. Aniline See ANILINE plus Oleum. n-Butyraldehyde See n-BUTYRALDEHYDE plus Oleum. Cresol See CRESOL plus Oleum. Cumene See CUMENE plus Oleum. Dichloroethyl Ether See DICHLOROETHYL ETHER plus Oleum. Diethylene Glycol See DIETHYLENE GLYCOL MONO. Monomethyl Ether METHYL ETHER plus Oleum. Diisobutylene See DIISOBUTYLENE plus Oleum. Epichlorohydrin See EPICHLOROHYDRIN plus Oleum. Ethyl Acetate See ETHYL ACETATE plus Oleum. Ethylene Cyanohydrin Mixing oleum and ethylene cyanohydriu in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). Sce Note under complete reference. Ethylene Diamine See ETHYLENE DIAMINE plus Oleum. Ethylene Glycol See ETHYLENE GLYCOL plus OLEUM. Ethylene Glycol See ETHYLENE GLYCOL MONOETHYL Monoethyl Ether ETHER ACETATE plus Oleum. Acetate 621 REVISIONS TO NFPA NO. 491M 491M-103

Ethylcneimine Mixing oleum and ethyleneimine in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Glyoxal See GLYOXAL plus Oleum. Hydrochloric Acid Mixing oleum and 36% hydrochloric acid ill a closed container c,msed the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Hydrofluoric Acid Mixing oleum and 48.7% hydrofluoric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Isoprene See ISOPRENE plus Oleum. Isopropyl Alcohol Mixing olcum and isopropyl alcohol in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Mesityl Oxide See MESITYL OXIDE plus Oleum. Methyl Ethyl Ketone See METHYL ETHYL KETONE plus Oleum. Nitric Acid Mixing oleum and 70% nitric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete referc~lce. 2-Nitropropane Mixing olcum ~md 2-nitropropane in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Propiolactone (BETA-) Mixing oleum and propiolactoue (BETA-) in closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete refcrencc. Propylene Oxide Mixing oleum and propylene oxide in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. 622 491M-104 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES Oleum (cont.) Pyridine Mixing oleuin and pyridine in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note trader complete reference. Sodium Hydroxide See SODIUM HYDROXIDE pha Oleum. Styrene Monomer Mixing oleuln and styrene monomer in a closed contai~mr caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Sulfolane Mixing oleum and sulfolane in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Vinyl Acetate Mixing oleum and vinyl acetate in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete rcfere~me. Vinylidene Chloride Mixing oleum and vinylidene chloride in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference.

ORGANIC MATTER Boron Trichloride See BORON TRICHLORIDE plus Nitrogen Peroxide. Bromine Monofluoride See BROMINE MONOFLUORIDE plus Water. Bromine Pentafluoride See BROMINE PENTAFLUORIDE plus Acetic Acid. Bromine Trifluoride See BROMINE MONOFLUORiDE plus Water. t-Butyl Peracetate See t-BUTYL PERACETATE plus Organic Matter. t-Butyl Perbenzoate See t-BUTYL PERBENZOATE plus Orga~fic Matter. Chloric Acid See ANTIMONY plus Chlorie Acid. Chlorine See BROMINE MONOFLUORIDE plus Water. Chlorine Monoxide See CHLORINE MONOXIDE plus Organic Matter. Chlorine Trifluoride See also BROMINE MONOFLUORIDE.plus Water. 623 REVISIONS TO NFPA NO. 491M 491M-105

Chlorine Trioxide See CHLORINE TRIOXIDE plus Organic Matter. Chromic Anhydride See CHROMIC ANHYDRIDE plus Organic Matter. Diisopropyl See DIISOPROPYL PEROXYDICARBON- Peroxydicarbonate ATE plus Organic Matter. Fluorine See FLUORINE. plus Organic Matter. Fluorine Perehlorate See FLUORINE PERCHLORATE plus Or- ganic Matter. Halogea Fluorides See BROMINE MONOFLUORIDE plus Water; see individual fluoride plus organic matter. Iodine Heptafluoride See BROMINE MONOFLUORIDE plus Water. Iodine Monoehloride See IODINE MONOCHLORIDE plus Or- ganic Matter. Iodine Pentafluoride See also BROMINE MONOFLUORIDE plus Water. Iodine Pentafluoride See also IODINE PENTAFLUORIDE plus Water. Lithium See LITHIUM plus Organic Matter. Peracetie Acid See PERACETIC ACID plus Organic Matter. Potassium Oxides See POTASSIUM plus Air. Potassium See POTASSIUM PERMANGANATE plus Permanganate Organic Matter.

ORGANIC SULFIDES RSR Calcium Hypoehlorite See CALCIUM HYPOCHLORITE plus Or- ganic Sulfides.

OSMIUM Os Chlorine Trifluoride See ANTIMONY plus Chlorine Trifluoride. Oxygen Difluoride See IRIDIUM plus Oxygen Difluoride.

OSMIUM-AMMINE NITRATES (self-reactive) Osmium-ammine nitrates may be impact- sensitive. Os(NH3)40~(N03)2 crystals are very unstable. MeUor 15:727 (1946-1947).

OSMIUM-AMMINE PERCHLORATES (self-reactive) Osmium-ammine perehlorates may be impact- sensitive. Mellor 15:727 (1946-1947). 624 401M-106 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

OXALIC ACID HO.CO.CO.OH FurfurylAlcohol See FURFURYL ALCOHOL plus Oxalic Acid.

OXALYL -BROMIDE C20,Br2 Sodium-Potassium See SODIUM-POTASSIUM ALLOY plus Alloy Oxalyl Bromide.

OXALYL CHLORIDE C~O2C12 Sodium-Potassium See SODIUM-POTASSIUM ALLOY plus Alloy 0xalyl Bromide.

OXIDIZING AGENTS Carbides See CARBIDES plus Oxidizing Agents.

OXYGEN 02 Aluminum See ALUMINUM Plus Oxygen. Boron Trichloride Oxygcn and boron trichloride react vigorously on sparking. Mellor 5:131 (1946-1947). Calcium Phosphide See SULFUR plus Calcium Phosphide. Chlorotrifluoroethylene See CHLOROTRIFLUOROETHYLENE plus and Bromine Oxygen and Bromine. Hydrazine Oxygen and hydrazine form explosive mixtures. Mellor 8, Supp. 2:72 (1967). Oxygen Difluoride and Violent explosions resulted when a spark was Water discharged in a mixture containing 25-70% oxygen difluoride in oxygen over water. Mellor 2, Supp. 1:191 (1956). Phosphine This reaction is explosive at ordinary temperatures. MeUor 8, Supp. 3:281 (1971). Phosphorus See PHOSPHORUS plus Oxygen. Potassium and Carbon See POTASSIUM plus Carbon Monoxide and Monoxide Oxygen. Potassium Peroxide The reaction of oxygen and potassium peroxide is violent at pressures of oxygen as low as 10 mm. Mellor 2, Supp. 3:1626 (1963). Tetrafluorohydrazine An explosive reaction of these two chemicals is likely in thc presence of organic matter. Mellor 8, Supp. 2:113 (1967).

OXYGEN (LIQUID) 02 Hydrazine Spontaneous ignition occurs when these chemicals are mixed. Mellor 8, Supp. 2:95 (1967). 625 REVISIONS TO NFPA NO. 491M 491M-107

OXYGEN DIFLUORIDE OF: Aluminum Chloride A vigorous reaction occurs between oxTgen difluoride and aluminum chloride, arsenic trioxide, chromic oxide, or phosphorus pentoxide. MeUor 2, Supp. 1:192 (1956). Ammonia Oxygeu difluoride and ammonia react immediately with white fumes. Mellor 2, Supp. 1:192 (1956). Arsenic Trioxide See OXYGEN DIFLUORIDE plus Aluminum Chloride. Bromine See BROMINE plus Oxygen Difluoride. Carbon Monoxide See HYDROGEN plus Oxygen Difluoride. Chlorine See CHLORINE plus Oxygen Difluoride. Chlorine and Copper See CHLORINE plus Oxygen Difluoride. Chromic Oxide See OXYGEN DIFLUORIDE plus Aluminum Chloride. Hydrogen See HYDROGEN plus Oxygen Difluoride. Hydrogen Sulfide Oxygen difluoride and hydrogen sulfide explode on mixing. Mellor 2, Supp. ! : 192 (1956). Iodine See BROMINE plus Oxygen Difluoride. Iridium See IRIDIUM plus Oxygen Difluoride. Methane See HYDROGEN plus Oxygen Difluoride. Osmium See IRIDIUM plus Oxygen Difluoride. Oxygen and Water See OXYGEN plus Oxygen Difluoride and Water. Palladium See IRIDIUM plus Oxygen Difluoride. Phosphorus Pentoxide See OXYGEN DIFLUORIDE plus Aluminum Chloride. Platinum See IRIDIUM plus Oxygen Difluoride. Rhodium See IRIDIUM plus Oxygen Difluoride. Ruthenium See IRIDIUM plus Oxygen Difluoride.

OZONE 03 Bromine Severe explosions occur in attempts to form tribromine octoxide from these reactants. Mellor 2, Supp. 1:748 (1956). Diallyl Methyl See DIALLYL METHYL CARBINOL plus Carbinol and Acetic Ozone and Acetic Acid. Acid Dinitrogen Pentoxide Mixtures of ozone and dinitrogen pentoxide are flammable or explosive. Mellor 8, Supp. 2:276 (1967). Ethylene Mellor 1 : 911 (1946-1947). 626 491M-108 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

Hydrogen Bromide These chemicals react instantaneously, ex- ploding except at low pressure of 2-3 mm mercury. Mellor 2, Supp. 1:736 (1956). Hydrogen Iodide The reaction between these chemicals is even more energetic than between ozone and hydrogen bromide. MeUor 2, Supp. 1:736 (1956). Nitric Oxide Mixtures of nitric oxide and ozone explode even when the quantity of ozone is small. Mellor 8:432 (1946-1947). Nitric Oxide Mixtures of ozo.ne and nitric oxide explode violently at liquid-air temperatures. Mellor 8, Supp. 2:164 (1967). Nitrogen Trichloride A mixture of ozone and nitrogen trichloride will explode. Mellor 1 : 911 (1946-1947). Nitrogen Triiodide Ozone and nitrogen triiodide form an explosive mixture. Mellor I : 911 (1946-1947). Nitroglycerin Ozone and nitroglycerin explode on mixing. Mellor 1:911 (1946-1947). Stibine MeUor 1:907 (1946-1947).

PALLADIUM Pd Oxygen Difluoride See IRIDIUM plus Oxygen Difluoride. PALLADIUM-AMMINE NITRATES (self-reactive) Palladium-ammine nitrates may be impact- sensitive. Pd(NH3)2(NO3)2 aud Pd (Nlis)4(NO~)~ detonate violently when heated. MeUor 15:685 (1946-1947). PALLADIUM-AMMINE PERCHLORATES (self-reactive) Palladiuna-ammine perchlorates may be im- pa ct-sensitive. MeUor 15:684 (1946-1947). PARATHION (C2I-IsO)2 P(S)OC6H,NO2 Endrin While a mixture of parathion and endrin were being blended into a petroleum solvent an exothermic reaction occurred which caused some of the solvent to vaporize. The solvent vapor-air mixture exploded. Overheating, possibly caused by mechanical agitation, started the exothermic reaction. Doyle (1973). 627 REVISIONS TO NFPA NO. 491M 491M:-109

PENTACHLOROETHANE C2HCI5 Sodium-Potassium See SODIUM-POTASSIUM ALLOY plus Alloy Bromoform.

PENTAMMINOAZIDOCOBALTIC AZIDE CoNa(NHa)5(N3)2 (self-reactive) Cobalt ammine azides explode violently on impact. Mellor 8, Supp. 2:48 (1967).

PENTAMMINOCHLOROCOBALTIC CHLORITE Co(NH3) sCI(CI02)2 (self-reactive) Pentamminochlorocobaltic chlorite contains an explosive combination of ions. Mellor 2, Supp. 1:575 (1956).

"PEROXY" ACIDS (PERFORMIC, PERACETIC, etc.) • (self-reactive) Peracids should be handled only in small quantities and with extreme care when pure or very concentrated. Organic peracids, such as peracetic acid, axe so unstable that they may explode during distillation, even under reduced pressure. Kirk and Othmer, Second Ed. 14:809 (1963). Grignard 11:90 (1935-1954).

PERACETIC ACID CH3CO.OOH Acetic Anhydride Acetic anhydride and peracetic acid react readily to form acetyl peroxide which is an extremely sensitive explosive. MCA Case History 1795 (1971). See also HYDROGEN PEROXIDE plus Acetic Anhydride. Organic Matter Upon contact with peracetic acid, organic materials can ignite or result in explosions. Haz. Chem. Data, p. 214 (1973).

PERCAMPHORIC ACID CsH14(COO.OH)2 (self-reactive) Percamphoric acid explodes when heated rapidly to 80 to 100 ° C. Chem. Reviews 45:15 (1949). 628

491M-110 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

PERCHLORATES Benzene Certain metal perchlorates recrystallized from benzenc or ethyl alcohol can explode spontaneously. J. Am. Chem. Soc. 62 (10) : 3524 (October 1940).

Ethyl Alcohol See PERCHLORATES plus Benzene.

PERCHLORIC ACID HCIO~ (self-reactive) After an animal carcass was dissolved in nitric acid, fat was skimmed off and 125 milliliters of perchloric acid was added. The sample was heated on a hot plate to dryness in a l-liter beaker after which two samples were placed on a stainless steel steam tray (steam off). When the samples were touched, they exploded. Chem. Eng. News. 51 (6): 29 (Feb. 5, 1973).

Acetic Anhydride The addition of acetic anhydride to an aqueous solution of perchloric acid causes the formation of acetic acid which can react violently with the perchloric acid. Rev. Met. 46 (8): 549-560 (1949). Mere. Poudres 32:179-196 (1950).

Bismuth See BISMUTH plus Perchloric Acid.

Dibutyl Sulfoxide A 70% perchloric acid solution reacts, in- stantly and explosively on contact with dibutyl sulfoxide. Wischmeyer (1973).

Ethyl Alcohol In mineral analysis the potassium cation is sometimes identified by adding perchloric acid in the presence of ethyl alcohol con- Centration.' Explosions frequently occur that are due to the spontaneous decomposition of ethyl perchlorate formed during concentration and of residual perchloric acid. With methyl alcohol, the reaction is identical except that the methyl perchlorate that is formed is very explosive. Analyst 80:10 (1955). 629 REVISIONS TO NFPA NO. 491M 491M-111

Fluorine See FLUORINE plus Perchloric Acid. Hydrochloric Acid See HYDROCHLORIC ACID plus Perehlorie Acid. Methyl Alcohol See PERCHLORIC ACID plus Ethyl Alcohol. Steel Explosions may occur when 72 percent perchloric acid is used for determination of chromium in steel. These explosions are apparently due to the formation of mixtures of perchlorie acid vapor and hydrogen, catalyzed by the presence of steel particles. The presence of steel burnings lowered the explosion temperatures of such mixtures to 215 ° C. Addition of a little water to keep the.Jr boiling temperature at 150 to 160 ° C pre- vented the formation of explosive gas mixtures. ACS 146, p. 189 (1960). Sulfuric Acid Pascal 16:298 (1931-1934). Sulfur Trioxide The reaction of anhydrous perchloric acid with sulfur trioxide is violent and accompanied by the evolution of considerable heat, even when diluted with an inert solvent such as chloroform. Pascal 16:300-303 (1931-1934).

PERCHLORYL FLUOROXIDE FCI04 See FLUORINE PERCHLORATE.

PERCHROMATES Aniline A mixture of aniline and a perchromate gives rise to an explosive reaction as the temperature is increased. Ri~st and Ebert, p. 297 (1948). Pyridine Heating a mixture of pyridine and a perchromate can lead to an explosion. Riist and Ebert, p. 297 (1948). Quinoline Heating a mixture of quinoline and perchromate can produce an explosion. Ri~st and Ebert, p. 297 (1948). 630 401M-112 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

PERFLUOROPROPIONYL FLUORIDE F3CCF~CO.F Fluorine An explosion occurred during the investigation of a new method of forming perfluoropropionyl hypofluorite. The method involved cooling the reactor to minus 50° C after which a 50-50 fluorine-nitrogen mixture was added to perfluoropropionyl fluoride. It is possible that a small amount of water, which may have been introduced due to the low temperature, converted some of the perfluoropropionyl fluoride to the perfluoropropionic acid, a precursor for the formation of one of the acyl hypofluorites. The latter are known to be explosive. MCA Case History 1045 (1966).

PERFORMIC ACID OCH00H (self-reactive) Performic acid is an unstable compound capable of undergoing rapid, spontaneous exothermal decomposition at room temperature, even in the absence of foreign substances. It is shock sensitive. Chem. Eng. News 28:3067 (Sept. 4, 1950). Chem. Reviews 45: 4, 7 (1949). Chem. Eng. News 30:3041 (1952). Aluminum See ALUMINUM plus Performie Acid. Aniline Aniline is oxidized violently by performic acid when the acid strength is more than 600/0 by weight. Berichte 48: 1139 (1915). Benzaldehyde • Benzaldehyde is oxidized violently by performic acid. Berichte 48:1139 (1915). Formaldehyde Formaldehyde is oxidized violently by coil: centrated performic acid. Berichte 48:1139 (1915). Lead Dioxide A concentrated solution of performic acid can explode upon contact with powdered lead dioxide. Berichte 48:1139 (1915). Magnesium See MAGNESIUM plus Performic Acid. Metal Oxides See METAL OXIDES plus Performic Acid. Metals See METAL plus Performic Acid. Nickel See NICKEL plus Performic Acid. Phosphorus See PHOSPHORUS plus Performic Acid. 631 REVISIONS TO NFPA NO. 491M 491M-113

Sodium Nitride Sodium nitride can decompose performic acid explosively. Berichte 48: 1139 (1915). Zinc See ZINC plus Performic Acid.

PEROXIDES ROOR Thiocyanates See THIOCYANATES plus Oxidizing Agents.

PEROXYACETIC ACID CHaCO.OOH See PERACETIC ACID.

PEROXYCAMPHORIC ACID CsH,,(COO.OH)2 See PERCAMPHORIC ACID.

PEROXYFORMIC ACID OCHOOH See PERFORMIC ACID.

PEROXYTRICHLOROACETIC ACID C13CCO0.OH See PERTRICHLOROACETIC ACID.

PERTRICHLOROACETIC ACID C13CCOO.OH (self-reactive) Pertrichloroacetic acid is very unstable. De- composition products include phosgene, chlorine, hydrochloric acid and carbon monoxide. Chem. Reviews 45 (1) : 10 (1949).

PETROLEUM Nitrogen Tetroxide .See "NITROGEN TETROXIDE plus Petro- leum.

PHENYL-LITHIUM LiCsH6 Nitrous Oxide The reaction of phenyl-lithium produces unstable lithium phenylazoxide as a product. Mellor 2, Supp. 2:93 (1961).

PHOSGENE 0CC12 Aluminum See ALUMINUM plus Phosphorus Trichlo- ride. 2, 4-Hexadiyn-1, Phosgene and 2, 4-hexadiyn-1, 6-diol react 6-Diol to form 2, 4-hexadiyn-1, 6-bischloroformate, which is a shock-sensitive compound. P. E. Driedger and H. V. Isaacson, Chem. Eng. News 50 (12): 51 (1972). Isopropyl Alcohol See ISOPROPYL ALCOHOL plus Phosgene. Potassium See POTASSIUM plus Phosgene. Sodium See SODIUM plus Phosgene. 632 491M-114 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

PHOSPHANES PxHy (self-reactive) The higher phosphanes (beyond P2H4) decompose rapidly in light at room temperature. M.ellor 8, Supp. 3:274 (1971).

PHOSPHINE PHa Boron Trichloride See BORON TRICHLORIDE plus Nitrogen Peroxide. Oxygen . See OXYGEN plus Phosphine. Potassium and See POTASSIUM plus Phosphine and Am- Ammonia mmfia.

PHOSPHONITRILE AZIDE-TRIMER (self-reactive) This is a highly explosive compound, readily detonated by friction. Mellor 8, Supp. 2:23 (1967).

PHOSPHONIUM PERCHLORATE 2PHa.3HCIO4 (self-reactive) Violent explosions have occurred in spite of every precaution. Helv. Chim. Acta 17:222-4 (1934). This is a very explosive salt and cannot be dried. MeUor 8, Supp. 3:274 (1971).

PHOSPHORUS P Boron Triiodide White or red phosphorus and boron triiodide react with incandescence. Mellor 5:136 (1946-1947). Cerium See CERIUM plus Phosphorus. Cesium Phosphorus reacts vigorously below 250 ° C with any of the following materials: cesium, lithium, potassium, rubidium, sodium, sulfur. Mellor 8, Supp. 3:228 (1971). Chlorates A mixture of red phosphorus and chlorates bursts into flames after a few moments. Moist chlorates explode on contact with white phosphorus. Mellor 2, Supp. 1:584 (1956). Chlorine The reaction of phosphorus and chlorine, fluorine, or bromine is highly exothermie. All can explode in contact with white phosphorus. Mellor 8, Supp. 3:228 (1971). The reaction of white phosphorus and liquid chlorine is explosive. Mellor 2, Supp. l: 379 (1956). 633 REVISIONS TO NFPA NO. 491M 491M-115

Chlorine and Heptane Flaming occurs when liquid chlorine in heptane is added to red phosphorus at 0 ° C. Mellor 2, Supp. 1:379 (1956). Chlorine Trifluoride See ANTIMONY plus Chlorine Trifluoride. Chromium Trioxide Mellor 11:234 (1946-1947). Copper See COPPER plus Phosphorus. Iodine Monobromide Phosphorus reacts violently with molten iodine monobromide or iodine monochloride. Mellor 8, Supp. 3: 264. Iodine Monochloride See PHOSPHORUS plus Iodine Monobromide. Iron See CO15PER plus Phosphorus. Lanthanum See CERIUM Plus Phosphorus. Lithium See LITHIUM plus Arsenic. See also PHOSPHORUS plus Cesium. Neodymium See NEODYMIUM plus Phosphorus. Nickel See COPPER plus Phosphorus. Nitryl Fluoride Red phosphorus and nitryl fluoride react at room temperature. Mellor 8, Supp. 3:264 (1971). Oxygen Phosphorus and oxygen or iodine undergo a vigorous reaction at room temperature. MeUor 8, Supp. 3:228 (1971). Performie Acid Red phosphorus is violently oxidized by performic acid. Grignard 11:179 (1935-1954). Ber/ch/e 48:1139 (1915). Platinum See COPPER plus Phosphorus. Potassium See PHOSPHORUS plus Cesium. Rubidium See PHOSPHORUS plus Cesium. Selenium Monochloride White phosphorus mixed with selenium monochloride explodes. Mellor 8, Supp. 3:264 (1971). Selenium Oxyfluoride This mixture ignites spontaneously. MeUor 8, Supp. 3:264 (1971). Selenium Tetrafluoride This mixture produces a violent reaction. Mellor 8, Supp. 3:264 (1971). Sodium See PHOSPHORUS plus Cesium. Sodium Chlorite Red phosphorus and sodium chlorite react in aqueous suspension in a strongly exothermic manner. The reaction can have a sudden, almost explosive stage. Mellor 8, Supp. 3:645 (1971). Sulfur See PHOSPHORUS plus Cesium. Vanadium This mixture produces an explosive reaction Oxytrichloride below 100° C with more than small amounts. Mellor 8, Supp. 3:264 (1971). 634 491M-116 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

PHOSPHORUS CYANIDE P3CN Air This very reactive cyanide ignites in air when touched with a warm rod. Mellor 8, Supp. 3:583 (1971). Water Phosphorus cyanide reacts violently with water. Mellor 8, Supp. 3:583 (1971).

PHOSPHORUS HEXAOXYTETRASULFIDE P408S~ Water This sulfide decomposes rapidly in moist air. Mellor 8, Supp. 3:437 (1971).

PHOSPHORUS ISOCYANATE PaOCN Acetaldehyde Phosphorus isocyanate and acetaldehyde, acetic acid, silver nitrate, or sulfuric acid react violently. Mellor 8, Supp. 3:585 (1971). Acetic Acid See PHOSPHORUS ISOCYANATE plus Acetaldehyde. Chlorine See CHLORINE plus Phosphorus Isocyanate. Silver Nitrate See PHOSPHORUS ISOCYANATE plus Acetaldehyde. Sulfuric Acid See PHOSPHORUS ISOCYANATE plus Acetaldehyde. Water The hydrolysis of phosphorus isocyanate is rapid. MeUor 8, Supp. 3:585 (1971).

PHOSPHORUS PENTACHLORIDE PC16 Potassium See POTASSIUM plus Boron Tribromide. Sodium See SODIUM plus Cobaltous Bromide.

PHOSPHORUS PENTOXIDE P205 Ammonia Reaction of phosphorus pentoxide and ammonia is rapid, contrary to older reports. Mellor 8, Supp. 1:331 (1964). This is a vigorous reaction. Mellor 8, Supp. 3:403 (1971). Calcium Oxide See CALCIUM OXIDE plus Phosphorus Pentoxide. Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Ar- senic Trioxide. Oxygen Difluoride See OXYGEN DIFLUORIDE plus Aluminum Chloride. Sodium Carbonate See SODIUM CARBONATE plus Phosphorus Pentoxide: Sodium Hydroxide See CALCIUM OXIDE Plus Phosphorus Pentoxide. 635 REVISIONS TO NFPA NO. 491M 491M-117

PHOSPHORUS TETRAOXYTRISULFIDE P~O4S3 Water The sulfide ignites if moistened with a little water. Mellor 8, Supp. 3:437 (1971).

PHOSPHORUS TRIBROMIDE PBr3 Potassium See POTASSIUM plus Boron Tribromide. Ruthenium Tetroxide See RUTHENIUM TETROXIDE plus Phos- phorus Tribromide. Sodium See SODIUM Plus Cobaltous Bromide.

PHOSPHORUS TRICHLORIDE POl3 Aluminum See ALUMINUM plus Phosphorus Trichloride. Diallyl Phosphite and See DIALLYL PHOSPHITE plus Allyl Allyl Alcohol Alcohol and Phosphorus Trichloride. Iodine Monochloride See IODINE MONOCHLORIDE plus Phos- phorus Trichloride.

PHOSPHORUS TRIFLUORIDE PF3 Diborane The reaction product of this combination, borane-phosphorus trifluoride compound, is spontaneously flammable in air. Mellor 8, Supp. 3:442 (1971).

PHOSPHORUS TRIFLUORIDE-BORANE COMPOUND HaBPF3 (self-reactive) See PHOSPHOROUS TRIFLUORIDE plus Diborane.

PHOSPHORUS TRIOXIDE P406 Arsenic Trifluoride See ARSENIC TRIFLUORIDE plus Phos- phorus Trioxide. Dimethyl Formamide See DIMETHYL FORMAMIDE plus Phos- phorus Trioxide. Dimethyl Sulfoxide See DIMETHYL FORMAMIDE plus Phos- phorus Trioxide. Dimethyl Sulfite See DIMETHYL FORMAMIDE plus Phos- phorus Trioxide. Methanol See DIMETHYL FORMAMIDE plus Phos- phorus Trioxide.

PHOSPHORYL BROMODIFLUORIDE POBrF2 Water See PHOSPHORYL FLUORIDE plus Water. 636 491M-118 REPORT OF COMMITTEE ON CHEMICALSAND EXPLOSIVES

PHOSPHORYL CHLORIDE POCI3 Boron Triiodide Phosphoryl chloride and boron triiodide react vigorously. Mellor 5:136 (1946-1947). Sodium See SODIUM plus Phosphoryl Chloride.

PHOSPHORYL CHLORODIFLUORIDE POC1F2 Water See PHOSPHORYL FLUORIDE plus Water.

PHOSPHORYL DIBROMOFLUORiDE POBr~F Water See PHOSPHORYL FLUORIDE plus Water.

PHOSPHORYL DICHLOROFLUORIDE POCI~F Water See PHOSPHORYL FLUORIDE plus Water.

PHOSPHORYL FLUORIDE POF3 Water The hydrolysis of phosphoryl fluoride and the halofluorides (phosphoryl chlorodifluoride, phosphoryl dichlorofluoride, phosphoryl bromodifluoride, and phosphoryl dibromofluoride) is a vigorous reaction. Mellor 8, Supp. 3:458 (1971).

PHTHALIC ACID HOCO.CsH4CO.OH Nitric Acid See PHTHALIC ANHYDRIDE plus Nitric Acid.

PHTHALIC ANHYDRIDE CeH4CO.OCO I I Nitric Acid The exothermic nitration of phthalic acid or phthalic anhydride by a fuming nitric acid -- sulfuric acid mixture may give mixtures of the potentially explosive phthaloyl nitrates or ni- trites or their nitro derivatives. Formation of these compounds may be avoided if the nitrat- ing mixture is extensively diluted with sulfuric acid and if a small (1.5 mole equivalent) of nitric acid is present. Chem. & Ind. 20:790 (1972). Chem. & Ind. 17:664 (1972).

PLATINUM Pt Bromine Trifluoride Platinum is attacked by bromine trifluoride at and Potassium 280 ° C in presence of potassium fluoride. Fluoride Mellor 2, Supp. 1:164 (1956). Oxygen Difluoride See IRIDIUM plus Oxygen Difluoride. Phosphorus See COPPER plus Phosphorus. ,637 REVISIONS TO NFPA NO. 491M 491M-119

PLATINIC BROMIDE PtBr4 Bromine Trifluoride See BROMINE TRIFLUORIDE plus Platinic Bromide.

PLATINIC CHLORIDE PtC14 Bromine Trifluoride See BROMINE TRIFLUORIDE plus Platinie Bromide.

PLATINOUS HYPOPHOSPHITE Pt(PH~02)~ (serf-reactive) Platinous hypophosphite liberates spontaneously flammable phosphine above 130° C. Mellor 8:890 (1946-1947).

PLATINUM-AMMINE NITRATES (self-reactive) Platinum-ammine nitrates may be impact- sensitive. Pt(NHa)~NOa and Pt(NH3)~(OH)~ (N08)2 detonate when heated. Mellor 16:412 (1946-1947).

PLATINUM-AMMINE PERCHLORATES (self-reactive) Platinum-ammine perehlorates may be impact- sensitive. Mellor 16:412 (1946-1947).

POLYCHLORINATED BIPHENYL Chlorine See CHLORINE plus Polychlorinated Bi- phenyl.

POLYDIMETHYLSILOXANE [-Si(CH3)~O-]x Chlorine See CHLORINE plus Polypropylene.

POLYISOBUTYLENE [CH~:C(CH~)d~ " Silver Peroxide See SILVER PEROXIDE plus Polyiso- butylene.

POLYPHOSPHORYL CHLORIDES Water These polymers hydrolyze violently. Mellor 8, Supp. 3:507 (1971).

POLYPROPYLENE (CH2:CHCH3)x Chlorine See CHLORINE plus Polypropylene. Potassium See POTASSIUM PERMANGANATE plus Permanganate Polypropylene.

POTASSIOPHOSPHINE KPH2 (See POTASSIUM DIHYDROPHOSPHIDE) 638

491M-120 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

POTASSIUM K (See IODINE plus Lithium). Air The higher oxides of Potassium , formed in air, react explosively with pure potassium, sodium, sodium-potassium alloys, and orgaific matter. Mellor 2, Supp. 3:1559 (1963). Aluminum Bromide A mixture of potassium and ally of the following metallic halides produces a strong explosion on impact: aluminum bromide, aluminum chloride, aluminum fluoride, ammonium ehlorocuprate, antimony tribromide, antimony trichloride, antimony triiodide, arsenic trichloride, arsenic triiodide, bismuth tribromide, bismuth trichloride, bismuth triiodide, cadmium bromide, cadmium chloride, cadlnium iodide, chromium tetrachloridc, cupric bromide, cupric chloride, cuprous bromide, cuprous chloride, cuprous iodide, manganous chloride, mercuric bromide, mercuric chloride, mercuric fluoride, mercuric iodide, mercurous chloride, nickel bromide, nickel chloride, nickel iodide, silicon tetrachloride, silver fluoride, stamfic chloride, stamfic iodide (with sulfur), stannous chloride, sulfur dibromide, thallous bromide, vanadium pentachloride, zinc bromide, zinc chloride, and zinc iodide. Mellor 2, Supp. 3" 1571 (1963). Aluminum Chloride See POTASSIUM plus Aluminum Bromide. Aluminum Fluoride See POTASSIUM plus Aluininum Bromide. Ammonium See POTASSIUM plus Aluminum Bromide. Chlorocuprate Ammonium Bromide A mixture of potassium and any of the following compounds produces a weak explosion on impact: ammonium brolnide, ammonium iodide, cadmium fluoride, chromium trifluoride, manganous bromide, manga~mus iodide, nickel fluoride, potassium ehlorocuprate, silver chloride, silver iodide, strontium iodide, thallous chloride, and zinc fluoride. Mellor 2, Supp. 3:1571 (1963). Ammonium iodide See POTASSIUM plus Ammonium Bromide. Antimony Tribromide See POTASSIUM plus Alumimun Bromide. Antimony Trichloride See POTASSIUM plus Aluminum Bromidc. Antimony Triiodide See POTASSIUM plus Aluminum Bromide. Arsenic Trichloride See POTASSIUM plus Aluminum Bromide. Arscnic Triiodide See POTASSIUM plus Aluminum Bromide. 639 REVISIONS TO NFPA NO. 491M 491M-121

Arsine and Ammonia Potassium and arsine react vigorously ill liquid ammonia at minus 78° C. The product reacts vigorously with air. Mellor 2, Supp. 3:1579 (1963). Bismuth Tribromide See POTASSIUM plus Aluminum Bromide. Bismuth Trichloride See POTASSIUM plus Aluminum Bromide. Bisnmth Triiodide See POTASSIUM plus Aluminum Bromide. Boric Acid A mixture of potassium and any of the following compounds may explode on impact: boric acid, copper oxychloride, lead oxychloride, lead peroxide, lead sulfate, silver iodate, sodium iodate, and vanadium oxychloride. Mellor 2, Supp. 3:1571 (1963). Boron Tribromide A mixture of potassium and any of the following halide compounds produces a very violent explosion on impact: boron tribromide, carbon tetrachloride, cobaltous bromide, cobaltous chloride, ferric bromide, ferric chloride, ferrous bromide, ferrous chloride, ferrous iodide, phosphorus pentachloride, phosphorus tribromide and sulfur dichloride. Mellor 2, Supp. 3:1571 (1963). Cadmium Bromide See POTASSIUM plus Aluminum Bromide. Cadmium Chloride See POTASSIUM plus Aluminum Bromide. Cadmium Fluoride See POTASSIUM plus Ammonium Bromide. Cadmium Iodide See POTASSIUM plus Aluminum Bromide. Carbon See POTASSIUM plus Graphite and Potassium Superoxide. Carbon Dioxide Mixture of solid forms of potassium, and carbon dioxide (as dry ice) explodes when subjected to shock. MeUor 2, Supp. 3:1568 (1963). Carbide Monoxide The reaction of potassium and carbon monoxide and Oxygen forms an explosive carbonyl compound, potassium carbonyl, which reacts violently with oxygen. Mellor 2, Supp. 3:1567 (1963). See also SODIUM CARBONYL plus Air. Carbon Tetrachloride See POTASSIUM plus Boron Tribromide. Charcoal Both charcoal and graphite react vigorously with liquid potassium. Mellor 2, Supp. 3:1566 (1963). Chlorine Trifiuoride See ANTIMONY plus Chlorine Trifluoride. Chromium See POTASSIUM plus Aluminum Bromide. Tetrachloride Chromium Trifluoride See POTASSIUM plus Ammonium Bromide. 640 491M-122 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES Potassium (cont.) Cobaltous Bromide See POTASSIUM plus Boron Tribromide. Cobaltous Chloride See POTASSIUM plus Boron Tribromide. Copper Oxychloride See POTASSIUM plus Boric Acid. Cupric Bromide See POTASSIUM plus Aluminum Bromide. Cupric Chloride See POTASSIUM plus Aluminum Bromide. Cuprous Bromide See POTASSIUM plus Aluminum Bromide. Cuprous Chloride See POTASSIUM plus Aluminum Bromide. Cuprous Iodide See POTASSIUM plus Aluminum Bromide. Ferric Bromide See POTASSIUM plus Boron Tribromide. Ferric Chloride See POTASSIUM plus Boron Tribromide. Ferrous Bromide See POTASSIUM plus Boron Tribromide. Ferrous Chloride See POTASSIUM plus Boron Tribromide. Ferrous Iodide See POTASSIUM plus Boron Tribromide. Graphite See POTASSIUM plus Charcoal. Graphite and Potassium Superoxide • MeUor 2, Supp. 3" 1566 (1963). Hydrogen Iodide A very violent explosion results when a mixture of potassium and hydrogen iodide is struck by a hammer. Mellor 2, Supp. 3:1563 (1963). Hydrogen Peroxide See LEAD DIOXIDE plus Hydrogen Peroxide. Iodine See IODINE plus Lithium. Iodine Monobromide Potassium in contact with molten iodine monobromide creates a strong explosion. Melh)r 2, Supp. 3:1563 (1963). Iodine Monochloride Mellor, 2, Supp. 1:501 (1956). Mellor, 2, Supp. 3:1563 (1963). Lead Oxychloride See POTASSIUM plus Boric Acid. Lead Peroxide See POTASSIUM plus Boric Acid. Lead Sulfate See POTASSIUM plus Boric Acid. Manganous Bromide See POTASSIUM Plus Ammonium Bromide. Manganous Chloride See POTASSIUM plus Aluminum Bromide. Manganous Iodide See POTASSIUM plus Ammonium Bromide. Mercuric Bromide See POTASSIUM plus Aluminum Bromide. Mercuric Chloride See POTASSIUM plus Aluminum Bromide. • Mercuric Fluoride See POTASSIUM plus Aluminum Bromide. Mercuric Iodide See POTASSIUM plus Aluminum Bromide. Mercurous Chloride See POTASSIUM plus Aluminum Bromide. Nickel Bromide See POTASSIUM .plus Aluminum Bromide. Nickel Chloride See POTASSIUM plus Aluminum Bromide. Nickel Fluoride See POTASSIUM plus Ammonium Bromide. Nickel Iodide See POTASSIUM plus Aluminum Bromide. Nitryl Fluoride Heated potassium metal burns with a lilac flame in vapor of nitryl fluoride. Mellor 2, Supp. 3:1566 (1963). 641 REVISIONS TO NFVA NO. 491M 491M-123 Potassium (cont.) Phosgene Mixture of potassium and phosgene explodes when subjected to shock. Mellor 2, Supp. 3:1568 (1963). Phosphine and Potassium and phosphine react in liquid Ammonia ammoni~ to form potassium dihydrophosphide, a spontaneously flammable solid. Mellor 8, Supp. 3:283 (1971). Phosphorus See PHOSPHORUS plus Cesium. Phosphorus See POTASSIUM plus Boron Tribromide. Pentachloride Phosphorus Tribromide See POTASSIUM plus Boron Tribromide. Potassium See POTASSIUM plus Ammonium Bromide. Chlorocuprate Potassium Oxides See POTASSIUM plus Air. Potassium Ozonide Potassium in contact'with the following oxides causes an explosive reaction: potassium ozonide, potassium peroxide, potassium superoxide. Mellor 2, Supp. 3:1577 (1963). Potassium Peroxide See POTASSIUM plus Potassium Ozonide. Potassium Superoxide See POTASSIUM plus Potassium Ozonide. Selenium Monochloride MeUor 2, Supp. 3:1564 (1963). Silicon Tetrachloride See POTASSIUM plus Aluminum Bromide. Silver Chloride See POTASSIUM plus Ammonium Bromide. Silver Fluoride See POTASSIUM plus Aluminum Bromide. Silver Iodate See POTASSIUM plus Boric Acid. Silver Iodide See POTASSIUM plus Ammonium Bromide. Sodium Iodate See POTASSIUM plus Boric Acid. Sodium Nitrite and Solutions of potassium and sodium nitrite in Ammonia liquid ammonia form disodium nitrite, which is very reactive and easily explosive. MeUor 2, Supp. 3:1566 (1963). Stannic Chloride See POTASSIUM plus Aluminum Bromide. Stannous Chloride See POTASSIUM plus Aluminum Bromide. Stannic Iodide and See POTASSIUM plus Aluminum Bromide. Sulfur Strontium Iodide See POTASSIUM plus Ammonium Bromide. Sulfur Vapors of potassium and sulfur react with chemiluminescence at 300° C and low pressures. Mellor 2, Supp. 3:1564 (1963). Sulfur'Dibromide See POTASSIUM plus Aluminum Bromide. Sulfur Dichloride See POTASSIUM plus Boron Tribromide. Thallous Bromide See POTASSIUM plus Aluminum Bromide. Thallous Chloride See POTASSIUM plus Ammonium Bromide. Vanadium Oxychloride See POTASSIUM plus Boric Acid. Vanadium See POTASSIUM plus Aluminum Bromide. Pentachloride Water Mellor 2, Supp. 3:1560 (1963). 642 491M-124 REPORT OF COMMITTEEON CHEMICALSAND EXPLOSIVES Potassium (cont.) Zinc Bromide See POTASSIUM plus Aluminum Bromide. Zinc Chloride See POTASSIUM plus Aluminum Bromide. Zinc Fluoride See POTASSIUM plus Ammonium Bromide. Zinc Iodide See POTASSIUM plus Aluminum Bromide.

POTASSIUM AZIDODISULFATE KNa(SO4)2 Water This reaction is an explosive one. Mellor 8, Supp. 2:36 (1967).

POTASSIUM BROMATE KBrOa Lead Acetate During an attempt to make lead bromate, an explosion occurred that caused two deaths. Mellor 2, Supp. 1:770 (1956). Selenium See SELENIUM plus Potassium Bromate.

POTASSIUM BROMIDE KBr Bromine Trifluoride See BROMINE TRIFLUORIDE plus Potas- sium Bromide.

POTASSIUM CARBONATE K~C03 Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Nitric Acid.

POTASSIUM CARBONYL KCO Oxygen See POTASSIUM plus Carbon Monoxide and Oxygen.

POTASSIUM CHLORATE KC103 Ammonium Chloride See POTASSIUM CHLORATE plus Am- monium Salts. Ammonium Salts The reaction of potassium chlorate with ammonium salts is violent. Mellor 2, Supp. 1:586 (1956). Boron See BORON plus Potassium Chlorate. Sulfur See SULFUR plus Potassium Chlorate.

POTASSIUM CHLORIDE KC1 Bromine Trifluoride See BROMINE TRIFLUORIDE plus Potas- sium Bromide.

POTASSIUM CHLOROCUPRATE K~CuCI4 Potassium See POTASSIUM plus Ammonium Bromide.

POTASSIUM DICHROMATE K2Cr207 Hydrazine Potassium dichromate or sodium dichromate reacts explosively with hydrazine. Mellor 11:234 (1946-1947). 643 REVISIONS TO NFPA NO. 491M 491M-125

POTASSIUM DIHYDROPHOSPHIDE KPH2 (self-reactive) See POTASSIUM plus Phosphine and Am- monia.

POTASSIUM FERROCYANIDE K4Fe(CN)6.3H~O Cupric Nitrate See CUPRIC NITRATE plus Potassium Ferrocyanide.

POTASSIUM FLUORIDE KF Platinum and See PLATINUM plus Bromine Trifluoride and Bromine Trifluoride Potassium Fluoride.

POTASSIUM HYDROXIDE K0H N-Methyl-N-Nitroso See N-METHYL-N-NITROSO UREA plus Urea aad Potassium Hydroxide and Methylene Chloride. Methylene Chloride

POTASSIUM IODIDE KI Bromine Trifluoride See BROMINE TRIFLUORIDE plus Potas- sium Bromide. Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Nitric Acid.

POTASSIUM NITRATE KNO3 Fluorine See FLUORINE plus Potassium Nitrate.

POTASSIUM OXIDES KxOy Potassium See POTASSIUM plus Air. Sodium See POTASSIUM plus Air. Sodium-Potassium See POTASSIUM plus Air. Alloy Organic Matter See POTASSIUM plus Air.

POTASSIUM OZONIDE KO3 Potassium See POTASSIUM plus Potassium Ozonide. Sodium See SODIUM plus Potassium 0zonide. Water Both potassium ozonide and potassium superoxide react explosively with water. Both are too unstable to be isolated. Mellor 2, Supp. 3:1631 (1963).

POTASSIUM HYDROXIDE KOH Chlorine and See CHLORINE plus Hydrogen peroxide and Hydrogen Peroxide Potassium Hydroxide. o-Nitrophenol Molten ortho nitrophenol reacts violently with potassium hydroxide (commercial 85% pellets). Pouwels (1972). 644 491M-126 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

N-Nitrosomethylurea A reaction between n-nitrosomethylurea and potassium hydroxide in n-butyl ether resulted in an explosion due to the formation of diazomethane. Schwab (1972). Nitrosomethyl Urea See NITROSOMETHYL UREA plus Potas- and Methylene sium Hydroxide and Methylene Chloride. Chloride Sodium Azide and See SODIUM AZIDE plus Benzoyl Chloride Benzoyl Chloride and Potassium Hydroxide.

POTASSIUM HYPOBORATE KBOH3 (self-reactive) Potassium hypoborate is a stronger, more violent reducing agent than potassium hypophosphite. McUor 5:37 (1946-1947).

POTASSIUM NITRATE KN03 Sodium Hypophosphite A mixture of potassium nitrate and sodium hypophosphite constitutes a powerful explosive. Mellor 8:881 (1946-1947). Trichloroethylene See TRICHLOROETHYLENE plus Potas- sium Nitrate.

POTASSIUM p-NITROBENZENE-DIAZOSULFONATE 02N-CaHr4-N :NS03K (self-reactive) While a chemist was examining some crystals of potassium p-nitrobenzene-diazosulfonate with. a loupe the entire 10-gram batch, which was on a sheet of filter paper, exploded. The crystals were probably the "labile" form (potassium p- nitrobenzene-sya-diazosulfonate) and would have in time converted to the "stable" form. Crucible 58 (9): 147 (1973).

POTASSIUM PERCHLORATE Fluorine See FLUORINE plus Potassium Perchlorate.

POTASSIUM PERMANGANATE KMnO~ Hydrogen Peroxide Potassium permanganate can produce an explosion when brought into contact with very concentrated hydrogen peroxide. Haz. Chem. Data, p. 230 (1973). 645' REVISIONS TO NFPA NO. 491M 491M-127

Organic Matter An explosive reaction can occur when solid, finely divided potassium permanganate comes in contact with organic substances. Pascal 16:1041 (1931-1934). Pieters, p. 28 (1957). Haz. Chem. Data, p. 230 (1973). Polypropylene Potassium permanganate being conveyed through a polypropylene tube ignited the tube. MCA Case History 1842 (1972). Sulfuric Acid Permanganate anhydride, Mn2OT, forms in tile course of the reaction of concentrated sulfuric acid with crystallized potassium permanganate at low temperature (minus 20° C). An oily liquid forms under the layer of sulfuric acid that is very unstable and detonates when the temperature is increased (70° C). Ri2st and Ebert, p. 29 (1948). Pieters, p. 28 (1957). Gallais, pp. 696, 697 (1957).

POTASSIUM PEROXIDE K~O2 Air See POTASSIUM PEROXIDE plus Water. Oxygen See OXYGEN plus Potassium Peroxide. Water Potassium peroxide is very reactive, and can explode in air or water. Mellor 2, Supp. 3:1577 (1963).

POTASSIUM SUPEROXIDE KO~ Sodium See SODIUM plus Potassium Ozonide. Water See POTASSIUM OZONIDE plus Water.

POTASSIUM TERT.-BUTOXIDE KOC(CH3)3 Acetic Acid See ACETONE plus Potassium Tert.-Butoxide. Acetone See ACETONE plus Potassium Tert.-Butoxide. Butyl Acetate See ACETONE plus Potassium Tert.-Butoxide. Carbon Tctrachloride See ACETONE plus Potassium Tert.-Butoxide. Chloroform See ACETONE plus Potassium Tert.-Butoxide. Diethyl Sulfate See ACETONE plus Potassium Tert.-Butoxide. Dimethyl Carbonate See ACETONE plus Potassium Tert.-Butoxide. Epichlorohydrin See ACETONE plus Potassium Tert.-Butoxide. Ethyl Acetate See ACETONE plus Potassium Tert.-Butoxide. Ethyl Alcohol See ACETONE plus Potassium Trrt.-Butoxide. Isopropyl Alcohol See ACETONE plus Potassium Tert.-Butoxide. Methyl Alcohol See ACETONE plus Potassium Tert.-Butoxide. Methylene Chloride See ACETONE plus Potassium Tert.-Butoxide. Methyl Ethyl Ketone See ACETONE plus Potassium Tert.-Butoxide. Methyl Isobutyl See ACETONE plus Potassium Tert.-Butoxide. Ketone 646 491M-128 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

Propyl Alcohol See ACETONE plus Potassium Tert.-Butoxide. Propyl Formate See ACETONE plus Potassium Tert.-Butoxide. Sulfuric Acid See ACETONE plus Potassium Tert.-Butoxide.

POTASSIUM TRIPERCHROMATE K3CrOO4 (self-reactive) Potassium triperchromate decomposes explosively at 178° C. The impure salt is explosive. Mellor 11:356 (1946-1947).

PROPANE CH3CH2CH3 Chlorine Dioxide See CHLORINE DIOXIDE plus Butadiene.

1-PROPANETHIOL Calcium Hypochlorite See CALCIUM HYPOCHLORITE plus 1- Propanethiol.

PROPIOLACTONE (BETA-) OCO.CH~CH= I I 2-Aminoethanol See-2-AMINOETHANOL plus Propiolaetone. Ammonium Hydroxide Mixing propiolactone (BETA-) and 28~O ammonium hydroxide in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Aniline See ANILINE plus Propiolactone. Chlorosulfonie Acid Mixing propiolactone (BETA-) and chlorosulfonic acid in a closed c(~r/tainer caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Ethylene Diamine See ETHYLENE DIAMINE plus Propiolae- tone (BETA-). Ethyleneimine See ETHYLENEIMINE plus Propiolactone (BETA-). Hydrochloric Acid Mixing propiolactone (BETA-) and 36% hydrochloric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Hydrofluoric Acid Mixing propiolactone (BETA-) and 48.7~0 hydrofluoric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. 647 REVISIONS TO NFPA NO. 491M 491M-129

Nitric Acid Mixing propiolactone (BETh-) and 70% nitric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Oleum See OLEUM plus Propiolactone (BETh-). Pyridine See PYRIDINE plus Propiolactone (BETh-). Sodium Hydroxide See SODIUM HYDROXIDE plus Propiolac- tone (BETh-). Sulfuric Acid Mixing propiolactone (nETh-) and 96% sulfuric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference.

PROPYL ALCOHOL CH3CH~CH2OH Potassium Tert.- See ACETONE plus Potassium Tert.-Butoxide. Butoxide

PROPYLENE H3CCH :CH2 Nitrous Oxide See NITROUS OXIDE plus Propylene.

PROPYLENE OXIDE CH3CHCH20 1 ! Ammonium Hydroxide Mixing propylene oxide and 28% ammonium hydroxide, in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Chlorosulfonic Acid Mixing propylene oxide and chlorosulfonic acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete refernece. Hydrochloric Acid Mixing propylene oxide and hydrochloric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Hydrofluoric Acid Mixing propylene oxide and 48.7% hydrofluoric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. 648

491M-130 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

Nitric Acid Mixing propylene oxide and 70% nitric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970)'. See Note under complete reference. Oleum See OLEUM plus Propylene Oxide. Sulfuric Acid Mixing propylene oxide and 96% sulfuric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference.

PROPYL FORMATE. C3HTOCHO Potassium Tert.- See ACETONE plus Potassium Tert.-Butoxide. Butoxide

PROPYL MERCAPTAN C3H~SH Calcium Hypochlorite See CALCIUM HYPOCHLORITE plus Mer- captan.

PYRIDINE N :CHCH :CHCH :CH t. I Chlorosulfonie Acid Mixing pyridine and chlorosulfonic acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Nitrie Acid Mixing pyridine and 70% nitric acid in a closed codtainer caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Gleam See OLEUM plus Pyridine. Perchromates See PERCHROMATES plus Pyridine. Propiolaetone (BETA-) Mixing pyridine and propiolactone (BETA-) in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Silver Perchlorate See SILVER PERCHLORATE plus Acetic Acid. Silver Pcrchlorate See SILVER PERCHLORATE plus Toluene. Sulfuric Acid Mixing pyridine and 96% sulfuric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. 649

REVISIONS TO NFPA NO. 491M 491M-131

PYRIDINIUM PERCHLORATE (C~H6N)CI04 (self-reactive) This salt may explode violently in contact with metals. Mellor 2, Supp. l: 603 (1956).

PYROPHOSPHORYL CHLORIDE P20aCI2 Water The vigorous hydrolysis of pyrophosphoryl chloride is like that of phosphorus pentoxide. Mellor 8, Supp. 3: 505.

PYROSULFURYL AZIDE (N3802)20 (self-reactive) Pyrosulfuryl azide decomposes explosively below 80 ° C. Mellor 8, Supp. 2:36 (1967).

I I OUINOLINE CHCHCHCHCCNCHCHCH I I Perehromates See PERCHROMATES plus Quinoline.

RHENIUM Re Fluorine Rhenium and fluorine react readily at 125° C. Mellor 2, Supp. 1:64 (1956).

RHODIUM Rh Chlorilm Trifluoride See ANTIMONY plus Chlorine Trifluoride. Oxygen Difluoride See IRIDIUM plus Oxygen Difluoride.

RHODIUM-AMMINE NITRATES (self-reactive) Rhodium-ammine nitrates may be impact- sensitive. Rh(NHs)sI(N03)2 crystals explode when heated. Mellor 15:590 (1946-1947).

RHODIUM-AMMINE PERCHLORATES (self-reactive) Rhodium-ammine perehlorates may be impact- sensitive. Mellor 15:590 (1946-1947).

RHODIUM TETRABROMIDE RhBr4 Bromine Trifiuoride See BROMINE TRIFLUORIDE plus Potas- sium Bromide. 650 491M-132 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

RUBBER Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Rub- ber. Iodine Monochloride See IODINE MONOCHLORIDE plus Organic Matter. Lithium See LITHIUM plus Organic Matter.

RUBIDIUM Rb Chlorine See CESIUM plus Chlorine. Phosphorus See PHOSPHORUS plus Cesium.

RUBIDIUM AZIDE RbN3 (self-reactive) Rubidium azide decomposes at 321 ° C. Mellor 8, Supp. 2:43 (1967).

RUBIDIUM CARBIDE Rb~C~ Bromine See BROMINE plus Rubidium Carbide. Iodine See IODINE plus Cesium Carbide. Nitric Oxide See RUBIDIUM CARBIDE plus Sulfur Di- oxide. Selenium See SELENIUM plus Rubidium Carbide. Sulfur Dioxide Rubidium carbide ignites on warming in sulfur dioxide or nitric oxide vapor. Mellor 5:848 (1946-1947).

RUBIDIUM CHLORIDE RbC1 Bromine Trifluoride See BROMINE TRIFLUORIDE plus Barium Chloride.

RUTHENIUM Ru Oxygen Difluoride See IRIDIUM plus Oxygen Difluoride.

RUTHENIUM TETROXIDE Ru04 Phosphorus Ruthenium tetroxide and phosphorus tri- Tribromide bromide undergo a vigorous exothermic reaction. Mellor 8, Supp. 3:521 (1971).

SELENIUM Se Chlorates A moist mixture of selenium and any chlorates but the alkali chlorates becomes incandescent. Mellor 2, Supp. 1:583 (1956). Chlorine Trifluoride See ANTIMONY plus Chlorine Trifluoride. Lithium Carbide See SULFUR plus Lithium Carbide. Potassium Bromate The reaction is violently explosive. MeUor 2, Supp. 1:763 (1956). 651 REVISIONS TO NFPA NO. 491M 491M-133

Rubidium Carbide The carbide burns in selenium vapor. Mellor 5: 848 (1946-1947). Silver Bromate The reaction is violently explosive. Mellor 2, Supp. 1:766 (1956).

SELENIUM IODOPHOSPHIDE Se3P412 Nitric Acid These compounds react explosively. Mellor 8, Supp. 3:247 (1971).

SELENIUM MONOCHLORIDE Se2Cl~ Phosphorus See PHOSPHORUS plus Selenium Mono- chloride.

SELENIUM OXYFLUORIDE SeOF~ Phosphorus See PHOSPHORUS plus Selenium Oxyfluoride.

SELENIUM TETRAFLUORIDE SeF4 Phosphorus See PHOSPHORUS plus Selenium Tetra- fluoride.

SILANES Air Mellor 1:376 (1946-1947).

SILICATES Lithium See LITHIUM plus Carbides.

SILICON Si Chlorine See ANTIMONY plus Chlorine Trifluoride. Cobaltic Fluoride A mixture of silicon powder and cobaltic fluoride glows red on gently warming. Mellor 2, Supp. 1:64 (1956). Sodium-Potassium The reaction of silicon and sodium-potassium Alloy alloy forms sodium silicide, which is spontaneously flammable in air. Mellor 2, Supp. 2:564 (1961). See also SODIUM SILICIDE plus Air.

SILICON TETRACHLORIDE SiCI4 Potassium See POTASSIUM plus Aluminum Bromide. Sodium See SODIUM plus Aluminum Bromide.

SILICON TETRAAZIDE Si(N3)4 (self-reactive) Spontaneous explosions have been observed with this compound. Mellor 8, Supp. 2:50 (1967). See BORON TRIAZIDE (self-reactive). 652 491M-134 REPORT OF COMMITTEE ON CHEMICALSAND EXPLOSIVES

SILVER Ag Chlorine Trifluoride See ALUMINUM plus Chlorine Trifluoride. Hydrogen Peroxide Finely divided silver and a strong hydrogen peroxide solution may explode. Mellor 1:936 (1946-1947).

SILVER AZIDE AgN3 (self-reactive) Silver azide decomposes at 250 ° C. It is explosively unstable. Mellor 8, Supp. 2:43 (1967). Silver azide is shock-sensitive when dry and has a detonation temperature of 250 q C. Photo. Sci. & Eng. 10 (6): 334-337 (1966). See also AZIDES.

SILVER BROMATE AgBr03 Sulfur See SULFUR plus Silver Bromate. Tellurium See TELLURIUM plus Silver Bromate.

SILVER CHLORATE AgC1Oa Sulfur See SULFUR plus Silver Chlorate.

SILVER CHLORIDE AgC1 Bromine Trifiuoride See BROMINE TRIFLUORIDE plus Barium Chloride, Potassium See POTASSIUM plus Ammonium Bromide.

SILVER CYANIDE AgCN Fluorine See FLUORINE plus Silver Cyanide.

SILVER FLUORIDE AgF Potassium See POTASSIUM plus Aluminum Bromide. Sodium See SODIUM pltis Aluminum Bromide.

SILVER FULMINATE AgON :C (self-reactive) Silver fulminate is shock-sensitive when dry and has a detonation temperature of 175° C. Photo. Sci. & Eng. 10 (6): 334-337 (1966). SILVER IODATE AgI03 Potassium See PoTAssIUM plus Boric Acid.

SILVER IODIDE AgI Potassium See POTASSIUM plus Ammonium Bromide. 653 REVISIONS TO NFPA NO. 491M 491M-135

SILVER NITRATE AgN03 Chlorine Trifluoride See CHLORINE TR1FLUORIDE plus Nitric Acid. Phosphorus Isocyanate See PHOSPHORUS ISOCYANATE plus Acet- aldehyde.

SILVER NITRIDE Ag3N (self-reactive) Silver nitride can be detonated by shock even if wet. Detonation temperature is 100 ° C. Photo. Sci. & Eng. 10 (6): 334-337 (1966). Dried silver nitride explodes readily, even from a strong flash of light. Mellor 8, Supp. 1:155 (1964).

SILVER OSMIAMATE AgOsN03 (self-reactive) Silver osmiamate detonates violently at 80 ° C or by percussion. Mellor 15:728 (1946-1947).

SILVER OXALATE Ag0C0.C0.OAg (self-reactive) Newly prepared silver oxalate, that had been oven dried for several days at 50 ° C maximum, was placed in a mechanical mortar-and-pestle type grinder. When the motor was turned on, an explosion occurred that seriously injured two people. Impact detonation was the prob- able cause of. the ,detonation. Textbooks indicate'that silver oxalate is explosive above 150°C and that the explosion hazard is moderate when exposed to heat. BCISC 44 (175): 19 (1973). Chlorine See CHLORINE plus Mercuric Oxide.

SILVER PERCHLORATE AgCI04 Acetic Acid Silver perchlorate-acetic acid solvated salt is liable to explode when struck. Shock-sensitive solvated salts are also formed with silver perchlorate and aniline, benzene, chlorobenzene, glycerol, nitrobenzene, pyridine, and toluene. Mellor 2, Supp. 1:616 (1956). Aniline See SILVER PERCHLORATE plus Acetic Acid. Benzene See SILVER PERCHLORATE plus Acetic Acid. 654

491M-136 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

Carbon Tetrachloride Thc reaction of silver perchlorate with carbon and Hydrochloric tetrachtoride in the presence of a small amount Acid of hydrochloric acid produces trichloromethyl perehlorate, which detonates at 40 ° C. Kirk and Othmer, Second Ed. 5:72 (1963). Pascal 16:316 (1931-1934). Chlorobenzene See SILVER PERCHLORATE plus Acetic Acid. Glycerol See SILVER PERCHLORATE plus Acetic Acid. Nitrobenzene See SILVER PERCHLORATE plus Acetic Acid. Pyridine See SILVER PERCHLORATE plus Acetic Acid. Toluene See SILVER PERCHLORATE plus Acetic Acid. Toluene Many "hydrocarbon-metal perchiorate" complexes are exposive, for example the complexes of benzene, toluene, aniline, pyridine, and dioxane. Analyst 81): 13 (1955).

SILVER PERCHLORATE-ACETIC ACID SOLVATED SALT AGC104:CH3COOH (self-reactive) See SILVER PERCHLORATE plus Acetic Acid.

SILVER PERMANGANATE AgMnO, Ammonium Hydroxide Silver permanganate reacts with ammonium hydroxide to form a complex of the formula [Ag(NH3)~]MnO~ which is shock senstiive. Pascal 16:1062 (1931-1934).

SILVER PEROXIDE Ag202 Polyisobutylene An explosion occurred during filling of a container with 2 kilograms of silver peroxide containing 1% by weight of polyisobutylene. Arbeitsschutz 6:248 (1972). SILVER SALTS Nitromethane Sec COPPER SALTS plus Nitromethane.

SODIUM ACETOACETIC ESTER IC~H2(NO2)~C6Hs 2-Iodo-3, See 2-IODO-3, 5-DINITROBIPHENYL plus 5-Dinitrobiphenyl Ethyl Sodio-Acetoacetate. 655 REVISIONS TO NFPA NO. 491M 491M-137

SILVER SULFIDE Ag2S Iodine Monochloride See IODINE MONOCHLORIDE plus Cad- mium Sulfide.

SODIUM Na Iodine See IODINE plus Lithium. Air MeUor 2, Supp. 2:440 (1961). Aluminum Bromide A mixture of sodium and any of the following halide compounds produces a strong explosion on impact: aluminum bromide, aluminum chloride, aluminum fluoride, ammonium chlorocuprate, antimony tribromidc, antimony trichloride, antimony triiodide, arsenic trichloride, arsenic triiodide, bismuth tribromide, bismuth trichloride, bismuth triiodide, boron tribromide, cupric chloride, ferrous chloride, iodine monobromide, manganous chloride, mercuric bromide, mercuric chloride, mercuric fluoride, mercuric iodide, mercurous chloride, silicon tetrachloride, silver fluoride, stannic chloride, stannic iodide (with sulfur), stannous chloride, sulfur dibromide, thallous bromide, vanadium pentaehloride, and zinc bromide. Mellor 2, Supp. 2:497 (1961). Aluminum Chloride See SODIUM plus Aluminum Bromide. Aluminum Fluoride See SODIUM plus Aluminum Bromide. Ammonium See SODIUM plus Aluminum Bromide. Chlorocuprate Antimony Tribromide See SODIUM plus Aluminum Bromide. Antimony Trichloride See SODIUM plus Aluminum Bromide. Antimony Triiodide See SODIUM plus Aluminum Bromide. Arsenic Trichloride See SODIUM plus Aluminum Bromide. Arsenic Triiodide See SODIUM plus Aluminum Bromide. Bismuth Tribromide See SODIUM plus Aluminum Bromide. Bismuth Trichloride See SODHJM plus Aluminum Bromide. Bismuth Triiodide See SODIUM plus Aluminum Bromide. Boron Tribromide See SODIUM plus Aluminum Bromide. Carbon Dioxide An explosive reaction occurs when dry ice and solid sodium are brought together by impact. Mellor 2, Supp. 2:468 (1961). Carbon Monoxide and The reaction of sodium and carbon monoxide Ammonia in liquid ammonia forms sodium earbonyl, which explodes when heated in air. Mellor 2, Supp. 2:467 (1961). See also SODIUM CARBONYL plus Air. 656 491M-138 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

Carbon Tetrachloride See SODIUM plus Carbon Dioxide. Carbon Tetrachloride See SODIUM plus Cobaltous Bromide. Cobaltous Chloride See SODIUM plus Cobaltous Bromide Chlorine The vapors of sodium and chlorine react with a luminous flame. Mellor 2, Supp. 1:380 (1956). Chlorine Trifluoride See CALCIUM plus Chlorine Trifluoride. Chromium A mixture of sodium and chromium tetra- Tetrachloride chloride creates a very violent explosion on impact. Mellor 2, Supp. 2:497 (1961). Cobaltous Bromide A very violent explosion results when a mixture of sodium and any of the following is struck with a hammer: cobaltous bromide, carbon tetrachloride, cobaltous chloride, ferric bromide, ferric chloride, ferrous bromide, ferrous iodide, phosphorus pentachloride, phosphorus tribromide, sulfur dichloride. Mellor 2, Supp. 2:497 (1961). Cupric Chloride See SODIUM plus Aluminum Bromide. Ferric Bromide See SODIUM plus Cobaltous Bromide. Ferric Chloride See SODIUM plus Cobaltous Bromide. Ferrous Bromide See SODIUM plus Cobaltous Bromide. Ferrous Chloride See SODIUM plus Alumitlum Bromide. Ferrous Iodide See SODIUM plus Cobaltous Bromide. Fluorine Mellor 2, Supp. 2:450 (1961). Hydrogen Chloride Sodium reacts very vigorously with gaseous hydrogen chloride. Mellor 2, Supp. 2:452 (1961). Hydrogen Peroxide See LEAD DIOXIDE plus Hydrogen Peroxide. Hydrogen Sulfide A very rapid reaction results when moist gaseous hydrogen sulfide contacts sodium. Mellor 2, Supp. 2:456 (1961). Iodine See IODINE plus Lithium. Iodine Monobromide A mixture of sodium and iodine monobromide explodes when struck with a hammer. Mellor 2, Supp. 2:452 (1961). See also SODIUM plus Aluminum Bromide. Iodine Monochloride The reaction of sodium and iodine monochloride is vigorous when both materials are molten. Mellor 2, Supp. 2:451 (1961). Manganous Chloride See SODIUM plus Aluminum Bromide. Mercuric Bromide See SODIUM plus Aluminum Bromide. Mercuric Chloride See SODIUM plus Aluminum Bromide. Mercuric Fluoride See SODIUM plus Aluminum Bromide. 657 REVISIONS TO NFPA NO. 491M 491M-139 Sodium (cont.) Mercuric Iodide See SODIUM plus Aluminum Bromide. Mercurous Chloride See SODIUM plus Aluminum Bromide. Monoammonium An explosive reaction occurred when mono- Phosphate ammonium phosphate was used to extinguish a sodium fi.re. No reactions were experienced when sodium bicarbonate or potassium bicarbonate was used in a sodium fire. Bohling (1971). Nitric Acid Mellor 2, Supp. 2:452 (1961). Nitrogen Peroxide Gaseous sodium reacts with the vapors of nitrogen peroxide and nitrous oxide with marked luminescence at 260 ° C. Mellor 2, Supp. 2:463 (1961). Nitrous Oxide See SODIUM plus Nitrogen Peroxide. Phosgene Vapors of sodium and phosgene react with luminescence at about 260 ° C. Mellor 2, Supp. 2:470 (1961). Phosphorus See PHOSPHORUS plus Cesium. Phosphorus See also SODIUM plus Cobaltous Bromide. Pentachloride Phosphorus See SODIUM plus Cobaltous Bromide. Tribomide Phosphorus See also SODIUM plus Phosphoryl Chloride. Trichloride Phosphoryl Chloride Gaseous sodium reacts with the vapors of phosphoryl chloride andphosphorus trichloride with luminescence at 270 ° C. Mellor 2, Supp. 2:463 (1961). Potassium Oxides See POTASSIUM plus Air. Potassium Ozonide Sodium in contact with either potassium ozonide or potassium superoxide produces an explosive reaction. Mellor 2, Supp. 3:1577 (1963). Potassium Superoxide See SODIUM plus Potassium Ozonide. Selenium The reaction of sodium and selenium is lumines- cent above 300 ° C at low pressure. Mellor 2, Supp. 2:455 (1961). Silicon Tetrachloride See SODIUM plus Aluminum Bromide. Silver Fluoride See SODIUM plus Aluminum Bromide. Stannic Chloride See SODIUM plus Aluminum Bromide. Stanaic Iodide and See SODIUM plus Aluminum Bromide. Sulfur Stannous Chloride See SODIUM plus Aluminum Bromide. Sulfur Mellor 2, Supp. 2:455 (1961). Sulfur Dibromide See SODIUM plus Aluminum Bromide. 658 401M-140 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES Sodium (cont.) Sulfur l)ichloride A mixture of sodium and sulfur dichloride explodes when struck with a hammer. Mellor 2, Supp. 2:460 (1961). Sulfur Dioxide The reaction of sodium and sulfur dioxide is almost as vigorous as that between sodium and water. Mellor 2, Supp. 2:458 (1961). Sulfuric Acid Mellor 2, Supp. 2:453 (1961). Tellurium A vigorous reaction results whcn liquid tellurium is poured over solid sodium. MeUor 2, Supp. 2:455 (1961). Thallous Bromide See SODIUM plus Aluminum Bromide. Vanadium See SODIUM plus Aluminum Bromide. Pentachloride Vanadyl Chloride Sodium and vanadyl chloride react violently when heated to 180 ° C. Mellor 2, Supp. 2:496 (1961). Water See SODIUM plus Carbon Dioxide. Zinc Bromide Sce SODIUM plus Aluminum Bromide.

SODIUM ACETATE CH3COONa Fluorine See FLUORINE plus Sodium Acetate.

SODIUM AMIDE NaNH2 Chromic Anhydride Whe~ these solids are ground together, a vigorous reaction results. Mellor 11:234 (1946-1947).

SODIUM AMINO PHOSPHIDE NaNHPH2 (self-reactive) Sodium amino phosphide is spontaneously flammable in air. Lehman and 1Vilson, p. 50 (1949).

SODIUM AZIDE NaN3 (self-reactive) Sodium azide decomposes at 275°C. Mellor 8, Supp. 2:43 (1967). Benzoyl Chloride and The mixture of sodium azide and benzoyl Potassium chloride reacts spontaneously with evolution Hydroxide of heat in a potassium hydroxide solution. Mellor 8, Supp. 2:55 (1967). Chromyl Chloride The reaction of sodium azide and chromyl chloride is all explosive one. Mellor 8, Supp. 2:36 (1967). Copper A solution of sodium azide in copper pipe with lead joints formed copper azide and lead azide, both detonating compounds. Klotz (1973). 659 REVISIONS TO NFPA NO. 491M 491M-141

.. Lead See SODIUM AZI])E plus Copper. Nitric Acid The reaction of sodium azide and strong nitric acid is energetic. Mellor 8, Supp. 2:315 (1967).

SODIUM BICARBONATE NaHC0a Sodium- See SODIUM-POTASSIUM ALLOY plus Potassium Alloy Water.

SODIUM BROMIDE NaBr Bromine Trifluoride See BROMINE TRIFLUORIDE plus Potas- sium Bromide.

SODIUM CARBIDE Na2C2 Aluminum See MERCURY plus Sodium Carbide. Carbon Dioxide Sodium carbide ignites on warming in carbon dioxide. Mellor 5:848 (1946-1947). Chlorine See CHLORINE plus Sodium Carbide. Iron See MERCURY plus Sodium Carbide. Lead See Mercury plus Sodium Carbide. Mercury See MERCURY plus Sodium Carbide. Water An explosion of sodium carbide can occur in water if a large excess of carbide is present. MeUor 5:848 (1946-1947).

SODIUM CARBONATE Na2C03 Phosphorus Pentoxide The anhydrous reaction of sodium carbonate and phosphorus pentoxide, initiated by local heating, can generate relatively high temperatures. Mellor 8, Supp. 3:406 (1971).

SODIUM CARBONYL Na~C202 Air See also SODIUM plus Carbon Monoxide and Ammonia.

SODIUM CHLORATE NaCl03 Ammonium A bulk cargo of sodium chlorate became hot Thiosulfate while beir/g transported in a tank that had previously contained ammoaium thiosulfate. Under controlled laboratory conditions, a small quantity of ammonium thiosulfate in sodium chlorate could be made to decompose explosively. MCA Case History 2019 (April 1974). 660 401M-142 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

SODIUM CHLORIDE NaCl Bromine Trifluoride See BROMINE TRIFLUORIDE plus Pots,s- sium Bromide.

SODIUM CHLORITE NaCl02 (self-reactive) The trihydrate crystals of sodium chlorite explode 9 n percussion. Mellor 2, Supp. 1:573 (1956). Phosphorus See PHOSPHORUS plus Sodium Chlorite. Sulfur See SULFUR plus Sodium Chlorite.

SODIUM DICHROMATE Na2Cr207 Hydrazine See POTASSIUM DICHROMATE plus Hy- drazine.

SODIUM HYDROXIDE NaOH Acetic Acid Mixing sodium hydroxide and glacial acetic acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Acetic Anhydride Mixing sodium hydroxide and acetic arLhydride in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Allyl Chloride In contact with dry sodium hydroxide, hydrolysis may take place producing allyl alcohol. V entrone (1971). Acrolein Mixing sodium hydroxide and acrolein in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Nitric Acid. Chlorohydrin Mixing sodium hydroxide and chlorohydrin in a closed container caused the temperature and • pressure to increase. Flynn and Rossow (1970). See Note under com- plet~e reference. Chlorosulfonic Acid Mixing sodium hydroxide and chlorosulfonic acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. 661 REVISIONS TO NFPA NO. 491M 491M-143

Ethylene Mixing sodium hydroxide and ethylene cyano- Cyanohydrin hydrin in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under eom~ plete reference. Glyoxal Mixing sodium hydroxide and glyoxal in a closed container caused 'the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. .- Hydrochloric Acid Mixing sodium hydroxide and 36% hydrochloric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference." Hydrofluoric Acid Mixing .sodium hydroxide and 48.7.°-/0 hydrofluoric acid in a closed, container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Nitric Acid Mixing sodium hydroxide and 70% nitric acid in a closed container caused the temperature and pressUre to increase. Flynn and Rossow (1970). See Note under complete reference. i Oleum Mixing sodium hydroxide and oleum in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Phosphorus Pentoxide See CALCIUM OXIDE plus Phosphorus Pentoxide. Propiolactone (BETA-) Mixing sodium hydroxide and propiolactone (BETA-) in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Sulfuric Acid Mixing sodium hydroxide and 96% sulfuric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. 662 491M-144 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES Sodium Hydroxide (cont.) Tctrachlorobenzene In the manufacturing of the sodium salt of and Methyl trichlorophenol, sodium hydroxide, methyl Alcohol alcohol and tetrachlorobenzene were heated. During the heating process, the pressure suddenly increascd rapidly and an cxplosiou occurred. MCA Guide for Safety, Appendix 3 (1972).

SODIUM HYPOBORATE NaBOH3 (self-reactive) Sodium hypoborate is a stronger, more violent reducing agent than sodium hypophosphite. Mellor 5:37 (1946-1947).

SODIUM HYPOBROMITE NaOBr Cupric Salts Solutions of sodium hypobromite are decomposed by powerful catalytic action of cupric ions, eveu as impurities. Mellor 2, Supp. 1:751 (1956).

SODIUM HYPOCHLORITE NaOC1 (self-reactive) Anhydrous sodium hypochlorite is very explosive. Merck Index, p. 960 (1968). Ammonium Acetate Decomposition of sodiuln hypochlorite takes place withill a few seconds with the following salts: ammonium acetate, ammonium carbonate, ammonium nitrate, ammonium oxalate, and ammonium phosphate. Mellor 2, Supp. 1:550 (1956). Ammo~ium Carbonate See SODIUM HYPOCHLORITE plus Am- monium Acetate. Ammonium Nitrate See SODIUM HYPOCHLORITE plus Am- monium Acetate. Ammonium 0xalate See SODIUM HYPOCHLORITE plus Am- monium Acetate. Ammonium Phosphate See SODIUM HYPOCHLORITE plus Am- monium Acetate.

SODIUM HYPOPHOSPHITE NaPH20~ (self-reactive) Explosions can occur when hot sodium hypophosphite solution is evaporated. Mellor 8:881 (1946-1947). Air MeUor 8, Supp. 3:623 (1971). Potassium Nitrate See POTASSIUM NITRATE plus Sodium Hypophosphite. 663 REVISIONS TO NFPA NO. 491M 491M-145

Sodium Nitrate See SODIUM NITRATE plus Sodium Hypo- phosphite.

SODIUM IODATE NaI03 Hydrogen Peroxide Iodates decompose hydrogen peroxide cata- lytically. Mellor 1:940 (1946-1947). Potassium See POTASSIUM plus Boric Acid.

SODIUM IODIDE NaI Bromine Trifluoride See BROMINE TRIFLUORIDE plus Potas- sium Bromide.

SODIUM METHYLATE CH3ONa Methyl Azide and See METHYL AZIDE plus Dimethyl Malon- Dimethyl Malonate ate and Sodium Methylate.

SODIUM MONOXIDE Na~O Nitric Oxide Sodium monoxide and nitric oxide react vigorously above I00 ° C. Mellor 2, Supp. 2:629 (1961).

SODIUM NITRATE NAN03 Sodium Hypophosphite A mixture of sodium nitrate and sodium hypophosphite constitutes a powerful explosive. Mellor 8:831 (1946-1947).

SODIUM NITRIDE Na3N Air The reactivity of sodium nitride resembles that of sodium metal. MeUor 8, Supp. 1:154 (1964). Performic Acid See PERFORMIC ACID plus Sodium Nitride.

SODIUM NITRITE NaNO~ Lithium See LITHIUM plus Sodium Nitrite. • Potassium and See POTASSIUM plus Sodium Nitrite and Ammoaia Ammonia.

SODIUM OZONATE NaOa Acids Acids initiate a fast decomposition of sodium ozonate. Mellor 2, Supp. 2:641 (1961). Water Water initiates a fast decomposition of sodium ozonate. Mellor 2, Supp. 2:641 (1961). 664 491M-146 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

SODIUM PERCHLORATE NaCIO, Ammonium Nitrate A mixture of these chemicals is used as an explosive. Mellor 2, Supp. 1:608 (1956).

SODIUM PEROXIDE Na202 Manganese Dioxide The catalyzed decomposition of sodium peroxide with manganese dioxide may be violent. Mellor 2, Supp. 2:635 (1961). Sulfur Monochloride A violent reaction results on mixing sodium peroxide and sulfur monochloride. MeUor 2, Supp. 2:634 (1961).

SODIUM-POTASSIUM ALLOY NaK Bromoform Mixtures of sodium-potassium alloy and bromoform, tetrachloroethane, or pentachloroethane can explode on standing at room temperature. They are especially sensitive to impact. Mellor 2, Supp. 2:563 (1961). Carbon Dioxide Mellor 2, Supp. 2:563 (1961). Carbon Tetrachloride Mellor 2, Supp. 2:563 (1961). See also SODIUM-POTASSIUM ALLOY plus Water. Methyl Dichloride The mixture of sodium-potassium alloy and methyl dichloride detonates strongly if struck. Mellor 2, Supp. 2:563 (1961). Oxalyl Bromide A mixture of sodium-potassium alloy and either oxalyl bromide or oxalyl chloride explodes violently. Mellor 2, Supp. 2:564 (1961). Oxalyl Chloride See SODIUM-POTASSIUM ALLOY plus Oxalyl Bromide. Potassium Oxides See POTASSIUM plus Air. Silicon See SILICON plus Sodium-Potassium Alloy. Sodium Bicarbonate See SODIUM-POTASSIUM ALLOY plus Water. Tetrachloroethane See SODIUM-POTASSIUM ALLOY plus Bromoform. Pentachloroethane See SODIUM-POTASSIUM ALLOY plus Bromoform. Water Sodinm-potassinm alloy undergoes a violent reaction with certain extinguishing agents: water, sodium bicarbonate, carbon tetrachloride. Mellor 2, Supp. 2:564 (1961). 665 REVISIONS TO NFPA NO. 491M 491M-147

SODIUM SULFIDE Na2S N, N-Dichloromethyl See N, N-DICHLOROMETHYL AMINE Amine plus Sodium Sulfide.

SODIUM SUPEROXIDE Na02 (self-reactive) Sodium superoxide violently evolves oxygen above 250 ° C. Mellor 2, Supp. 2:639 (1961). Water The reaction of sodium superoxide and water is fast and vigorous, liberating oxygen. Mellor 2, Supp. 2:639 (1961).

SODIUM TETRAZOLYL-5-AZIDE NaNN:NN:CNNN I I (self-reactive) Sodium tetrazolyl-5-azide is a shock-sensitive compound. Chem. Eng. News 43 (52): 29, 30 (Dec. 27, 1965).

SODIUM TRIPERCHROMATE NaaCrO04 (self-reactive) Sodium triperchromate decomposes explosively at 115° C. Mellor 11:356 (1946-1947).

STANNIC CHLORIDE SnC15 Potassium See POTASSIUM plus Aluminum Bromide. Sodium See SODIUM plus Aluminum Bromide.

STANNIC IODIDE SnI4 Potassium and See POTASSIUM plus Aluminum Bromide. Sulfur Sodium and Sulfur See SODIUM plus Aluminum Bromide.

STANNIC OXIDE Sn02 Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Arsenic Trioxide.

STANNOUS CHLORIDE SnC12 Bromine Trifluoride See BROMINE TRIFLUORIDE plus Stan- nous Chloride. Potassium See POTASSIUM plus Aluminum Bromide. Sodium See SODIUM plus Aluminum Bromide.

STANNOUS FLUORIDE SnF12 Chlorine See CHLORINE plus Stannous Fluoride. 666 491M-148 REPORT OF COMg.fITTEE ON CHEMICALSAND EXPLOSIVES

STEEL Perchloric Acid See PERCHLORIC ACID plus Steel.

STRONTIUM CHLORIDE SrCI~ 2-Furan See 2-FURAN PERCARBOXYLIC ACID Percarboxylic Acid (self-reactive).

STRONTIUM IODIDE SrI2 Potassium See POTASSIUM plus Ammonium Bromide.

STRONTIUM PHOSPHIDE Sr3P2 Bromine See BROMINE plus Strontium Phosphide. Chlorine See CHLORINE plus Strontium Phosphide. Fluorine See FLUORINE plus Strontium Phosphide.

STYRENE MONOMER CH~ :CHC6H3 Chlorosulfonic Acid Mixing styrene monomer and chlorosulfonic acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Oleum See OLEUM plus Styrene Monomer. Sulfuric Acid Mixing styrene monomer and 96% sulfuric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference.

SULFAMIC ACID HSO3NH~ Nitric Acid Fuming nitric acid combined with sulfamic acid causes violent release of nitrous oxide. Mellor 8, Supp. 2:316 (1967).

SULFOLANE O2SCH2CH~CH~CH2 J f Chrosoulfonic Acid Mixing sulfolane and chlorosulfonic acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Oleum See OLEUM plus Sulfolane.

SULFUR S Ammonia The reaction of ammonia with specially prepared sulfur may form explosive sulfur nitride. Mellor 8, Supp. 1:330 (1964). 667 REVISIONS TO NFPA NO. 491M 491M-149

Barium Chlorate A mixture of sulfur and barium chlorate ignites at about 108 ° -- 111 ° C. Mellor 2, Supp. 1:583 (1956). Boron See BORON plus Sulfur. Bromates Mellor 2, Supp. 1:763 (1956). Calcium Phosphide Calcium phosphide reacts with sulfur or oxygen incandescently at about 300 ° C. Mellor 8: 841 (1946-1947). Chlorine Trifluoride See ANTIMONY plus Chlorine Trifluoride. Lead Chlorate A mixture of sulfur and lead chlorate ignites at about 63 ° -- 67 ° C. Mellor 2, Supp. 1:583 (1956). See also SULFUR plus Chlorates. Lithium See LITHIUM plus Sulfur. Lithium Carbide Lithium carbide burns in the vapor of sulfur or selenium. MeUor 5:848 (1946-1947). Potassium See POTASSIUM plus Aluminum Bromide. Potassium See POTASSIUM plus Sulfur. Phosphorus Trioxide Mellor 8, Supp. 3:436 (1971). Potassium Chlorate A mixture of sulfur and potassium chlorate ignites at about 160 ° -- 162° C. Mellor 2, Supp. 1:583 (1956). See also SULFUR plus Chlorates. Silver BrSmate An explosive reaction occurs in the presence of water. Mellor 2, Supp. 1:766 (1956). Silver Chlorate A mixture of sulfur and silver chlorate ignites at about 74° C. Mellor 2, Supp. 1:583 (1956). See also SULFUR plus Chlorates. Sodium and Stannic See SODIUM plus Aluminum Bromide. Iodide Sodium Chlorite Solid sulfur will ignite if mixed with solid sodium chlorite and moistened. MeUor 2, Supp. 1:572 (1956). Sulfur Dichloride See SODIUM plus Cobaltous Bromide.

SULFUR DIBROMIDE SBr2 Potassium See POTASSIUM plus Aluminum Bromide. Sodium See SODIUM plus Aluminum Bromide. / ! 668 491M-150 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

SULFUR DICHLORIDE SCI~ Aluminum See ALUMINUM plus Carbon Disulfide. Ammonia The reaction product of sulfur dichloride and ammonia is a powerful detonating compound, sulfur nitride. Mellor 8:624 (1946-1947). Potassium See POTASSIUM plus Boron Tribromide. Sodium See SODIUM plus Cobaltous Bromide. See SODIUM plus Sulfur Dichloride.

SULFUR DIOXIDE SO~ Aerolein See ACROLEIN plus Sulfur Dioxide. Aluminum See ALUMINUM plus Carbon Disulfide. Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Am- monia. Rubidium Carbide See RUBIDIUM CARBIDE plus Sulfur Dioxide.

SULFURIC ACID H2S04 Acetic Anhydride See ACETIC ANHYDRIDE plus Sulfuric Acid. Acetonitrile See ACETONITRILE plus Sulfuric Acid. Acrolein See ACROLEIN plus Sulfuric Acid. Acrylonitrile See ACRYLONITRILE plus Sulfuric Acid. Allyl Alcohol See ALLYL ALCOHOL plus Sulfuric Acid. Allyl Chloride See ALLYL CHLORIDE plus Sulfuric Acid. Allyl Chloride Allylchloride may polymerize violently under conditions involving an acid catalyst, such as sulfuric acid, ferric chloride, aluminum chloride, Lewis acids, and Ziegler type catalysts (initiators). Ventrone (1971). 2-Aminoethanol See 2-AMINOETHANOL plus Sulfuric Acid. Ammonium Hydroxide Mixing 96% sulfuric acid and 28% ammonia in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Ammonium See AMMONIUM TRIPERCHROMATE Tripcrchromate plus Sulfuric Acid. Aniline See ANILINE plus Sulfuric Acid. Bromine Pentafluoride See BROMINE PENTAFLUORIDE plus Nitric Acid. n-Butyraldehyde See n-BUTYRALDEHYDE plus Sulfuric Acid. Chlorates See CHLORATES plus Sulfuric Acid. 669 REVISIONS TO NFPA NO. 491M 491M-151

Chlorine Trifluoride Sec CHLORINE TR1FLUORIDE plus Nitric Acid. Chlorosulfonic Acid See CHLOROSULFONIC ACID plus Sulfuric Acid. Cuprous Nitride See CUPROUS NITRIDE plus Sulfuric Acid. Diisobutylenc See DIISOBIJTYLENE plus Sulfuric Acid. Epichlorohydrin See EPICHLOROHYDR1N plus Sulfuric Acid. Ethylene See ETHYLENE CYANOHYDRIN plus Cyanohydrin Sulfuric Acid. Ethylene Di~mine See ETHYLENE DIAMINE plus Sulfuric Acid. Ethylene Glycol Sec ETHYLENE GLYCOL plus Sulfuric Acid. Ethylenimine See ETHYLENIMINE plus Sulfuric Acid. Hydrochloric Acid See HYDROCHLORIC ACID plus Sulfuric Acid. Hydrofluoric Acid See HYDROFLUORIC ACID plus Sulfuric Acid. Iodine Hept~fluoride See IODINE HEPTAFLUORIDE plus Sul- furic Acid. Indane and See INDANE plus Nitric Acid and Sulfuric Nitric Acid Acid. Isoprene See ISOPRENE plus Sulfuric Acid. Mesityl Oxide See MESITYL OXIDE plus Sulfuric Acid. Nitric Acid and See NITRIC ACID plus Sulfuric Acid and Glycerides Glycerides. Phosphorus See PHOSPHORUS ISOCYANATE plus Isocyanate Acetaldehyde. Potassium Tert.- See ACETONE plus Potassium Tert.-Butoxide. Butoxide Piopiolactone See PROPIOLACTONE (BETh-) plus Sulfuric (SETh-) Acid. Propylene Oxide See PROPYLENE OXIDE plus Sulfuric Acid. Pyridine See PYRIDINE plus Sulfuric Acid. Sodium Hydroxide See SODIUM HYDROXIDE plus Sulfuric Acid. Styrene Monomer See STYRENE MONOMER plus Sulfuric Acid. Vinyl Acetate See VINYL ACETATE plus Sulfuric Acid.

SULFUR MONOCHLORIDE S~Cq., Sodium Peroxide See SODIUM PEROXIDE plus Sulfur Mono- chloride.

SULFUR NITRIDE $4N4 (self-reactive) Sulfur nitride detonates violently on impact. Mellor 8:624 (1946-1947). 670 491M-:152 REPORT OF COMMITTEE ON CHEMICA.LS AND EXPLOSIVES

SULFUR TRIOXIDE S03 Perchloric Acid See PERCHLORIC ACID plus Sulfur Tri- oxide. Tetrafluorethylene The reaction of sulfur trioxide in excess with tetrafluoroethylene causes explosive decoln- position to c~rbonyl fluoride and sulfur dioxide. Chem. Eng. News 49 (22) : 3 (1971). TANTALUM Ta Bromine Trifluoride See NIOBIUM plus Bromine Trifluoride.

TANTALUM PENTOXIDE Ta206 Bromine Trifluoride See BROMIN]~ TRIFLUORIDE plus Bis- muth Pentoxide. Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Alu- minum Oxide. Lithium See LITHIUM plus Tantalum Peutoxide.

TELLURIUM Te Chlorine Trifluoride See ANTIMONY plus Chlorine Trifluoride. Silver Bromate A vigorous reaction occurs in the prescnce of moisture. Mellor 2, Supp. 1:766 (1956). Sodium See SODIUM plus Tellurium.

TERPENES Nitric Acid See NITRIC ACID plus Diborane.

TETRABORON DECAHYDRIDE B4Ht0 Air This hydride ignites or explodes on exposure to air. Mellor 5:36 (1946-1947).

TETRABORON DECAHYDRIDE B4H6 Nitric Acid The mixture of tetraboron decahydride and nitric acid is explosive. Mellor 5:36 (1946-1947).

TETRACHLORETHANE CI2CHCHCI2 2, 4-Dilfitrophcnyl See 2, 4-DINITROBENZENE SULFENYL- Disulfide CHLORIDE (self-reactive).

TETRACHLOROBENZENE C14C6H2 Sodium Hydroxide See SODIUM HYDROXIDE plus Tetra- and Methyl Alcohol chlorobenzeneand Methyl Alcohol. 671 REVISIONS TO NFPA NO. 491]VI 491M-153

TETRACHLOROETHANE C2H2C14 Sodium-Potassium See SODIUM-POTASSIUM ALLOY plus Alloy Bromoform.

TETRAFLUOROETHYLENE CF2:CF2 Sulfur Trioxide See SULFUR TRIOXIDE plus Tetrafluoro- ethylene.

TETRAFLUOROHYDRAZINE F~NNF2 Nitrogen Trifluoride See NITROGEN TRIFLUORIDE plus Tetra- fluorohydrazine. Oxygen See OXYGEN plus Tetrafluorohydrazine.

TETRAHYDROFURAN OCH~CH2CH2CH~ I .I Lithium Alulninum Fire can occur when tetrahydrofuran is uscd as Hydride a solvent for lithium aluminum hydride. Peroxides of tetrahydrofuran or their reaction products probably caused ~ vigorous reaction with lithium aluminum hydride, and subsequent fire. MCA Guide for Safety, Appendix 3 (1972).

TETRAIODOETHYLENE I2HC:CHI2 Iodine Pentafluoride See IODINE PENTAFLUORIDE plus Tetra- iodoethylene.

TETRAMETHYLAMMONIUM CHLORITE (CH~)4NH~CI02 (self-reactive) Tetramethylammonium chlorite explodes on percussion. Mellor 2, Supp. 1:573 (1956).

TETRAMMINOCUPRIC CHLORATE Cu(NH3)4(CI03)2 (self-reactive) This compound will detonate when struck. Mellor 2, Supp. 1:592 (1956).

TETRAMMINOCUPRIC PERCHLORATE Cu(NH3)4(CIO4)2 (self-reactive) This compound will detonate when struck but. is less sensitive than tetramminoeupric chlorate. MeUor 2, Supp. l: 592 (1956). 672 491M-154 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

TETRAMMINODIAZIDOCOBALTIC AZIDE Co(N3)~(NH3)4N3 (self-reactive) See PENTAMMINO AZIDOCOBALTIC AZIDE (self-reactive).

TETRAMMINOZINC CHLORATE Zu(NH3)4(CIO~)2 (self-reactive) This compomld detonates when struck. Mellor 2, Supp. 1:592 (1956).

TETRAMMINOZINC PERCHLORATE Zn(NH3)4(CI04)2 (self-reactive) This compound detonates when struck but is less sensitivc than tetramminiozine chlorate. Mellor 2, Supp. 1:592 (.1956).

THALLIUM TRINITRATE TRIHYDRATE T1 (N03)3 Formic Acid and A violent reaction occurred when a small Vanillin amount of" vanillin was added to thallium trinitrate trihydrate (up to 50%) in 90% formic acid. Dean (1973).

THALLOUS AZIDE TIN3 (self-reactive). Thallous azide decomposes at 334 ° C. It is almost as unstable as the copper salt. Mellor 8, Supp. 2:43 (1967).

THALLOUS BROMIDE T1Br Potassium See POTASSIUM plus Aluminum Bromide. Sodium See SODIUM plus Aluminum Bromide.

THALLOUS CHLORIDE T1Cl Fluorine See FLUORINE plus Thallous Chloride. Potassium See POTASSIUM plus Ammonium Bromide.

THALLOUS PHOSPHIDE PTI~ Air This salt ignites if heated in air. Mellor 8, Supp. 3:312 (1971).

THIOCYANATES RSCN Organic Peroxides See THIOCYANATES plus Oxidizing Agents. Oxidizing Agents Caution should be exercised in treating a thiocyanate with an oxidizing agent such as a peroxide since such mixtures have been known to explode. Kharasch Vol. 1, p. 312 (1961). Peroxides See THIOCYANATES phis Oxidizing Agents. 673 REVISIONS TO NFPA NO. 491M 491M-155

THIODIGLYCOL (HOCH2CH2)2S Hydrogen Peroxide Thiodiglycol was being oxidized with an and Acetone excess of hydrogen peroxide using acetone as a solvent. At the conclusion the acetone and excess hydrogen peroxide were removed under vacuum in a steam bath. After about 15 minutes of heating on a steam bath, a violent explosion occurred. MCA Case History 223 (1962).

THIONYL CHLORIDE 0SC12 2, 4-Hexadiyn-1, Thionyl chloride and 2, 4-hexadiyn-1, 6-diol 6-Diol reacting in dimethyl formamide forms 2, 4- hexadiyn-1, 6-bischlorosulfite which is shock sensitive and decomposes violently upon distillation. P. E. Driedger and H. V. Isaacson, Chem. Eng. News 50 (12): 51 (1972). Water A flexible stainless hose that was being used for thionyl chloride transfer ruptured when contaminated with water. Water reacts with thionyl chloride liberating hydrogen chloride and sulfur dioxide gases. Wischmeyer (1972).

THIOUREA S:C(NH2)2 Acrolein See ACROLEIN plus Sulfur Dioxide.

THORIUM NITRIDE TH3N4 Water Thorium nitride hydrolyzes vigorously. Mellor 8, Supp. 1:182 (1964).

THORIUM PHOSPHIDE Th3P4 Acids Thorium phosphide reacts with acids to release spontaneously flammable phosphine. Mellor 8, Supp. 3:348 (1971).

TIN Sn Bromine The violent reaction between these chemicals is controlled in halocarbon solutions. Mellor 2, Supp. 1:715 (1956). Bromine Trifluoride Tin and bromine trifluoride regct violently. Mellor 2, Supp. 1:164 (1956). Chlorine Mellor 2, Supp. 1:380 (1956). Chlorine Trifluoride See ALUMINUM plus Chlorine Trifluoride. 674 491M-156 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

TITANIUM Ti ]~romineTrifluoride See MOLYBDENUM plus Bromine Tri- fluoride.

TITANIUM DIOXIDE Ti02 Lithium See LITHIUM plus Titanium Dioxide.

TOLUENE C6HsCH3 Nitrogen Tetroxide See NITROGEN TETROXIDE plus Toluene. Silver Perchlorate See SILVER PERCHLORATE plus Acetic Acid. Silver Perchlorate See SILVER PERCHLORATE plus Toluene.

TRIAMMINOTRIAZIDOCOBALT Co(Nai3(NH3)3 (self-reactive) See PENTAMMINOAZIDOCOBALTIC AZIDE (self-reactive).

TRIAZINE N:CHN:CHN:CH I I Nitric Acid See NITRIC ACID plus Triazine.

TRIBROMONEOPENTYL ALCOHOL (BrCH2-)3COH Ethyl Acetoacetate See ETHYL. ACETOACETATE plus Tri- and Zinc bromoneopentyl Alcohol and Zinc.

TRICHLOROETHYLENE CI~C:CHCI Potassium Nitrate A batch of 3257 grams of boron, 9362 grams of potassium nitrate, 989 grams of laminac, and 500 grams of trichloroethylene had been mixing for 5 minutes, when an explosion occurred. MCA Guide for Safety, Appendix 3 (1972).

TRICHLOROMETHYL PERCHLORATE ClaC(CI04) (self-reactive) See SILVER PERCHLORATE plus Carbon Tetraehloride and Hydrochloric Acid.

TRIFLUORONITROANILINE F3C6H(NOz)N :NOH (self-reactive) The recrystallized compound, which had been made from trifluoronitroaniline, hydrochloric acid and sodium nitrite, exploded violently on impact. MCA Guid'e for Safety, Appendix 3 (1972). 675 REVISIONS TO NFPA NO. 491M 491M-157

TRIHYDRAZINE NICKEL NITRATE Ni(NO3).3H2NNH2 (self-reactive) A small amount of thoroughly washed, dry trihydraz!ne nickel nitrate exploded about ten minutes after exposurc to the atmosphere. H. Ellcrn and D. E. Olander, J. Chem. Edu. 32:24 (1955).

TRIHYDRAZINOCADMIUM CHLORATE Cd(N2H4)ffCI03)2 (self-reactive) This compound detonates when struck. Mellor 2, Supp. 1:592 (1956).

TRIHYDRAZINOCADMIUM PERCHLORATE Cd(HzNNH~)ffC10~)2Cd See CADMIUM PERCHLORATE HYDRAZINATE.

TRIHYDRAZINOCOBALTOUS CHLORATE CO(N2H4)3(CIO~)~ (self-reactive) This compound detonates when struck. Mellor 2, Supp. 1:592 (1956).

TRIHYDRAZINONICKEL CHLORATE Ni(N2H4)ffC103)~ (self-reactive) This compound detonates when struck. Mellor 2, Supp. 1:592 (1956).

TRIMANGANESE TETROXIDE Mn30 4 Fluorine See FLUORINE plus Trimanganese Tetroxide.

TRINITROETHANOL (I~02) 3CCH20H (self-reactive) Explosions were encountered during the distillation of trinitroethanol. J. Am. Chem. Soc. 72:5329 (1950).

TRINITROMETHANE (NO2) 3CH (self-reactive) Explosions were encountered during the distillation of trinitromethane. J. Am. Chem. Soc. 72:5329 (1950). See also NITRIC ACID plus Acetylene.

TRISILYLPHOSPHINE SiH3P~ (self-reactive) This is a spontaneously flammable liquid. Mellor 8, Supp. 3:283 (1971).

TUNGSTEN W Bromine Trifluoride See MOLYBDENUM plus Bromine Tri- fluoride. Chlorine Trifluoride See ANTIMONY plus Chlorine Trifluoride. 676 491M-158 REPORT OF COMMITTEE ON CHE~'IICALS AND EXPLOSIVES

TUNGSTEN CARBIDE WC Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Mer- curic Iodide.

TUNGSTEN TRIOXIDE W03 Chlorine Trifluoride See also CHLORINE TRIFLUORIDE plus Aluminum Oxide. Lithium See LITHIUM plus Tungsten Trioxide.

UNSYMMETRICAL DIMETHYLHYDRAZINE H~NN(CH3)~ Nitric Oxide See NITRIC OXIDE plus Unsymmetrical Dimethylhydrazine.

URANIUM OXIDES UO2;UO3;U308 Bromine Trifluoride See BROMINE TRIFLUORIDE plus Uranium Oxides.

URANIUM PHOSPHIDE U3P4 Hydrochloric Acid Uranium phosphide reacts with hydrochloric acid to release spontaneously flammable phosphine. Mellor 8, Supp. 3:349 (1971).

URANYL PERCHLORATE UOz(CI04)~ Ethyl Alcohol Attempts at recrystallization from ethyl alcohol resulted in an explosion. Mellor 2, Supp. 1:617 (1956). p-URAZINE NHNHCO.NHNHCO I I (self-reactive) While a chemist was manipulating the material in a glass container, an explosion occurred that shattered the container. The material that exploded was probably a nitrogen-containing by- product: MCA Case History 144 (1966). UREA (N'H2)2CO Gallium Perchlorate See GALLIUM PERCHLORATE plus Urea.

VANADIUM V Bromine Trifluoride See MOLYBDENUM plus Bromine Tri- fluoride. Lithium See LITHIUM plus Vanadium.

VANADIUM OXYDICHLORIDE VOCI2 Potassium See POTASSIUM plus Boric Acid. 677 REVISIONS TO NFPA NO. 491M 491M-159

VANADIUM OXYTRICHLORIDE VOC13 Phosphorus See PHOSPHORUS plus Vanadium Oxytri- chloride.

VANADIUM PENTACHLORIDE VCI6 Potassium See POTASSIUM plus Aluminum Bromide. Sodium See SODIUM plus Aluminum Bromide.

VANADIUM PENTOXIDE Va~O~ Chlorine Trifluoride See CHLORINE TRIFLUORIDE plus Alu- minum Oxide. Lithium See LITHIUM plus Vanadium Pentoxide.

VANILLIN CH30(HO)C6H~CHO Thallium Trinitrate See THALLIUM TRINITRATE TRIHY- Trihydrate and DRATE plus Formic Acid and Vanillin. Formic Acid

VINYL ACETATE CH2:CHOCO.CH3 2-Aminoethanol See 2-AMINOETHANOL plus Vinyl Acetate. Chlorosulfonic Acid Mixing vinyl acetate and chlorosulfonic acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Ethylene Diamine See ETHYLENE DIAMINE plus Vinyl Acetate. Ethyleneimine Mixing vinyl acetate and ethyleneimine in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Hydrochloric Acid Mixing vinyl acetate and 36% hydrochloric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Hydrofluoric Acid Mixing vinyl acetate and 48.7% hydrofluoric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Nitric Acid Mixing vinyl acetate and 70% nitric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference. 678 491M-160 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

Oleum See OLEUM plus Vinyl Acetate. Sulfuric Acid Mixing vinyl acetate and 96% sulfuric acid in a closed container caused the temperature and pressure to increase. Flynn and Rossow (1970). See Note under complete reference.

VINYLIDENE CHLORIDE CH2:CCI2 Chlorosulfonic Acid Mixing vi~ylidenc chloride and ehlorosulfonie acid in a closed co,ltainer caused the temperature mid pressure to itlcrease. Flynn and Rossow (1970). See Note under complete reference. Nitric Acid Mixing vinylidene chloride and 70070 nitric acid in a closed cotltaitmr caused the temperature £ud pressure to increase. Flynn and Rossow (1970). See Note under complete reference. Oleum See OLEUM plus Vinylidene Chloride.

WAX, DRAWING Chlorine See CHLORINE plus Polypropylene.

ZIEGLER-TYPE CATALYSTS Allyl Chloride See SULFURIC ACID plus Allyl Chloride.

ZINC Zn Ammoniuln Nitrate Mellor 8, Supp. 1:546 (1964). Chlorine Trifluoride See ALUMINUM plus Chlorine Trifluoride. Chromic Anhydride A violent reaction or flaming is likely in the reaction of chromic anhydride and zinc dust. Mellor 11:237 (1946-1947). Ethyl Acetoacetatc See ETHYL ACETOACETATE plus Tri- and bromoneopentyl and Zinc. Tribromoneopentyl Alcohol Performic Acid Powdered zinc can decompose performic acid violently, causing an explosion. Bcrichte 48:1139 (1915).

ZINC BENZENEDIAZONIUM CHLORIDE C6Hs-N:NCI.ZnC12 (self-reactive) Zinc benzenedi,~zoniuln chloride had been washed in dry acetone and had been stored in a vacuum desiccator 15 hours when it exploded. Chem. & Ind. p. 58-9 (1956). 679 REVISIONS TO NFPA NO. 491M 491M-161

ZINC BROMIDE ZnBr2 Potassium See POTASSIUM plus Ahuninum 13romide. Sodium Sec SODIUM plus Aluminum Bromide.

ZINC CHLORIDE ZnCI= Potassium See POTASSIUM plus Aluminum Bromide.

ZINC FLUORIDE ZItF2 Potassium See POTASSIUM plus Amnaonium Bromide.

ZINC IODIDE ZI2 Potassium See POTASSIUM plus Alumium Bromide.

ZINC SULFIDE ZnS Iodine Monochloride See IODINE MONOCHLORIDE plus Cad- mium Sulfide. 2. Insert the following references in lheir proper alphabetical location in the list of complete references at the end of the text. Angew. Chem. Angewandte Chemie, Weinheim, West Germany Arbeitsschutz Arbeitsschutz, Bundesministen Fuer Arbeit and Sozialordnung, Cologne Barrett Communication, R. E. Barrett, Chevron Oil Field Research Com- pany, La Holra, Calif. Biul. Wojst~owej Akad. Tech. Biuletyn Wojskowski Akademii Techniczenj Imcni Jaroslawa Da- browskiego, Warsaw, Poland F. F. Chapman Communication, F. F. Chapman, Beckman Instrumcnts, Inc., Ful- lerton, Calif. Chem. Ber. Chemische Bcrichte, Weinheim- Bergstr., Wcst Germany Comb. & Flame Combustion and Flame, American Elsevier Publishing Co., Inc., New York Cond. Chem. Dict. The Condensed Chemical Diction- ary, Eighth Edition, Van Nost- rand Reinhold Co., Ncw York, N.Y., 1971 Crucible Crucible, Pittsburgh Section, A~nerican Chemical Socicty Dean Communication, F. H. Dean, On- tario Research Department, Sheri- dan Park, Ontario 680

491M-162 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES

Flynn and Rossow Classification of Chemical Reac- tivity Hazards for the Advisory Com- mittee to the U. S. Coast Guard, National Academy of Sciences. J. P. Flynn and H. E. Rossow, The Dow Chemical Company, Mid- land, Michigan (1970) NOTE: The authors observed temperature and pressure effects when equimolar quantities of two chemicals were mixed in a closed container. In some cases the changes were solely vapor pressure effects due to heat of solution. Gallais Chimie Mindrale Thdorique et Ex- p~rimerdale (Chimie Eleetronique), F. Gallais, Masson, Paris (1957) Gazz. Chim. Ital. Gazzetta Chimica Italiana, Rome, Italy Grignard Traite de Chimie Organique, Grig- nard, Dupont and Locquin, Mas- son, Paris (1935-1954) Helv. Chim. Acta Helvetica Chimica Acta, Basel, Switzerland Himiceskaja Promyslennost H imiceskaja Promyslennosl. Mirfis- try of Chemical Industry, Mos- cow (U.S.S.R.) J. Indian Chem. Soc. Journal of the Indian Chemical Society, Calcutta Kharasch Organic Sulfuric Compounds, W. Kharasch, Editor, Pergamon Press, Elmsford, N. Y. (1961) Kite Communication, G. F. Kite, phillip Morris Reseaxch Center, Rich- mond, Va. Ki~tila Dimethylformamide Chemical Uses, R. S. Kittila, E. I. duPont de Nemours, Wilmington, Del. (1967) Klot~ Communication, M. O. Klotz, Ot- tawa Civic Hospital, Ottawa, On- tario M atsuguma Communication, H. J. Matsuguma, Pieatinny Arsenal, Dover, N.J. MCA Guide for Safety Guide for Safety in the Chemical Laboratory (Second Edition), Van Nostrand Publishing Company, New York (1972) 681 REVISIONS TO NFPA NO. 491M 491M-163

Mere. Proc.°Manchester Lit. Phil. Soc. Memoirs and Proceedings of the Manchester Literary Philosophical Society, Manchester, England Merck Safety Report Merck & Co., Inc., Rahway, N.J. Mukerjee Communication, N. C. Mukerjee, Chemplast, P. O. Raman Nagar, Tamilnadu, India NSC Newsletter, Campus Safety Newsletter, Campus Safety Associ- ation, National Safety Council, Chicago Pascal Traite de chimie mindrale, Paul Pascal, Paris, Masson (1931-1934) Pouwels Communication, H. Pouwels, ACF Chemiefarma N. V., Maarssen, Netherlands Rolston Communication, C. H. Rolston, duPont Research and Develop- meat Center, WilmiJlgton, Del. Riist and Ebert Unfdlle Beim Chemischen Arbeiten, E. R/ist and A. Ebert, Rascher Verlag, Zdrich (1948) Scaros and Serauskas Communication, M. G. 'Scaros and J. A. Serauskas, Searle Labora- tories, Chicago Stephenson Communication, F. G. Stephenson, Manufacturing Chemists' Associ- ation, Washington, D.C. Tr. po KhOn. i Khim. Tekhnol. Trudy pc Khimii i Khimicheskoi Tekhnologii, Gorki, U.S.S.R. Von Schwartz and Salter Fire and Explosions Risks, E.Von Schwartz; Translated from the revised German edition by Charles T. C. Salter, Griffen & Co., Londoa (1940) Zh. Obshch. Khim. Zhurnol Obshchei Khimii, U.S.S.R. Z. Naturforsch Zeitschrift fuer Naturforschung, Tuebinger, West Germany

3. Make the following deletions and amendments to the reaction statements now in the text. a. Delete: ACETONE 1,1,1-Trichloroethane A mixture of 1,1,1-trichloroethane and acetone will undergo a highly exothermic condensation reaction when catalyzed by a base. Albrecht (1970). 682 491M-164 REPORT OF COMMITTEE ON CHEMICALS AND EXPLOSIVES b. Delete: CHLOROACETONE (self-reactive) Monochloroacetone exploded spontaneously during storage. Chem. Eng. News 9:29 (1931). c. Delete: DIMETHYLFORMAMIDE Aluminum and See ALUMINUM plus Organic Chlorides Organic Chlorides and Dimethylformamide or Dimethylaceta- mide. d. Revise: GOLD Ammonium Hydroxide Delete only: "It is believed the explosive sub- and Aqua Regia stance was gold fulminate." e. Delete: NITRIC ACID Furfuryl Alcohol See UNSYMMETRICAL DIMETHYL- HYDRAZINE plus Nitric Acid, Nitrogen Tetroxide, and Sulfuric Acid. f. Delete: PERCHLORIC ACID Ethyl AlcOhol A drop of anhydrous perchloric acid on ethyl alcohol causes a violent explosion. ACS 146: 188. Am. Chem. J. 23:444 (1900). g. Revise: SILVER CHLORIDE Ammonia Revise to read: "When a solution of silver chloride in aqueous ammonia is exposed to air or to heat, a material, probably silver nitride, is formed that is detonated violently by shock. Mellor 3:382 (1946-1947); J. K. Luchs, Phot. Sci. Eng. 10 (6): 334-7 (1966). Kite (1973)." 683 REVISIONS TO NFPA NO. 491M 491M-165 h. Delete: SODIUM HYPOCHLORITE Oxalic Acid Weighed quantities of the two chemicals were placed in a stainless steel beaker in preparation of a bleach solution. Just as water was first added, the mixture exploded. Sodium hypochlorite, a very very strong oxidizing ageilt, can react almost spontaneously with readily oxidizable materials, such as oxalic acid and cellulose. MCA Case History 839 (1962). i. Revise: SULFURIC ACID Water Revise first statement to read: "During sulfonation of mononitrobenzene by fuming sulfuric acid, a leak from an internal cooling coil permitted water to enter the tank. A violent eruption occurred due to the heat of solution." Delete the second statement.