U.S. Department Advisory of Transportation Federal Aviation Circular Administration Subject: Hand Fire Extinguishers for use in Aircraft Date: 01/14/11 AC No: 20-42D Initiated by: AIR-120 Change: This advisory circular (AC) gives you guidance for the fire-fighting effe tivenes selection and safe-use ofhand fire extinguishers in airplanes and rotorcraft. In it we will also show you how to gain Federal Aviation Administration (FAA) approval ofhand fire extinguishers for aircraft. ~~ ~ DavidW. Hempe Manager Aircraft Engineering Division ircraft Certification Service 01/14/11 AC20-42D Table of Contents Pa,·agraph Page Chapter 1. General Information about this Advisory Circular (AC) ................................. 1 1. What is the Purpose ofthis Advisory Circular (AC)? ........................................................ 1 2. Wbo is this AC for? ............................................................................................................ 2 3. What has Changed in this AC from the Previous AC? ............... ........................................ 2 4. Does this AC cancel any prior A Cs? .................................................................................. 3 5. Where Can 1find This AC and other FAA publications? ................................................... 3 Chapter 2. Gaining FAA Approval for Fire Extinguishers .................................................. 4 1. How are Hand Fire Extinguishers Approved? .................................................................... 4 2. How are Halon 1211 Replacement Extinguishers Approved? ........................................... 5 3. How are Halon Agents Approved? ..................................................................................... 7 Chapter 3. Selecting the Correct Hand Fire Extinguisher ................................................... 9 I. What are the Different Types ofPires?................................................. ,..... .......... .............. 9 2. What do the Noo1eral Ratings Mean? ................................................................................. 9 3. What Extinguishing Agents are Appropriate for the Different Types ofPires? ...... .. ......... 9 4. What Extinguishing Agents are Compatible witll Aircraft Materials? ............................. 11 5. What are the Operating Temperature Tolerances? .................................................... ...... 11 6. General Guidelines for Hand Fire Extinguishers? ................. ........................................... 12 Chapter 4. Safe Use ofHand Fire Extinguishers ..... _ ......................................................... 14 I. What Basic Fire Fighting Training Should be Proyjded? ................................................. 14 2. What are Some General Guidelines for the Safe-Use of Halocarbon Extinguishers? ........................................................................................... 15 3. How to Prevent Hypoxia in an Unpressurized Aircraft .................................................... 16 4. What are the Guidelines on the Selection ofHalocarbon Extinguishers? ......................... 17 5. How to Safely Use Halocarbon Extinguishers in Accessible Cargo Compartments ........ 19 6. How to Inspect and Maintain the Hand Fire Extinguisher for Continued Safe-Use.. ........................................................................................................ 20 ii 01/14/11 AC 20-42D Paragraph Page Chapter 5. Locating and Mounting Hand Fire Extinguishers ........................................... 22 1. Where to Locate and MoW1t Hand Fire Extinguishers in Passenger Compartments.................................................................................................. 22 2. How to Locate and Mount Hand Fire Extinguishers in Flight Deck Compartments .......................................................................................................... 23 3. How to Locate and Mow1t Hand Fire Extinguishers in Small Single Engine and Multiengine Aircraft ............................................... ,................................23 4. How Many !-:land Extinguishers Should I Install ................................................. ............. 23 Appendix 1. List of Acronyms ..... .................................. .................................................. Al -1 Appendix 2. Definitions and Terms .. ......... .. .......... ......................................................... A2-1 Appendix 3. Related Publications and How to Get Them ............................................ A3-1 I. Code ofFederal Regulations (CFR)........................................ ..................................... A3-1 2. FAA Airworthiness Directive (AD) .. .. .......................................................................... A3-1 3. PAA Advisory Circulars (AC)...................................................................................... A3-l 4. FAA Technical Standard Order (TSO)......................................................................... A3-2 5. f AA Safety Alerts for Operators (SAFOS) and lnformation for Operators (lnFOs) ... A3-2 6. FAA Training Videos ................................................................................................... A3-2 7. Reports and Papers ............................. .. ......... ........................................ ........................ A3-2 8. American Society ofTesting and Materials (ASTM) Standards ........... ....................... A3-4 9. Factory Mutual Research Corp. (FM) ........................................................................... A3-5 I 0. International Organization for Standardization (ISO) .................................................. A3-5 l l. National Fire Protection Association (NFPA) ........................ ............. ....................... .. A3-5 12. RTCA lnc. Documents ................................................................................................. AJ-6 13. SAE Documents............................................................................................................ AJ-6 14. Underwriters Laboratories, lnc (UL) ............................................................................ A3-6 iii 01/14/1 1 AC 20-420 Paragraph Page Appendix 4. Explanatory Material ................................................................................. A4-1 I. Effective Throw Ranges............................................................................................... A4- l 2. Safe-Use Guidance....................................................................................................... A4-1 3. Extinguisher Weights................................................................. ................................... A4-4 4. Aircraft Volumes and Ventilation......................................... ........................................ A4-5 Table of Figures Figure I. Relative Toxicity of 5 B:C Halocarbon Extinguishers ...................................J8 Figure 2. Mininmrn Number ofHand Fire Extinguishers Required for Transport Category Aircraft Passenger Compartments ....... ................................ ....... ............24 Figure 3. Minimum Number ofHand Fire Extinguishers Required for Transport Category Rotorcraft Passenger Compartments ......................,...............................25 Figure 4. Effective Throw Ranges for Halocarbon Halon Replacement and Water Extinguishers............................................................... ..............A4- l Figure 5. Safe-Use Agent WN for Halocarbon Extinguishers in Unventilated Passenger and Crew Compartments.... .... .... .......... ...............................A4-2 Figure 6. Multiplication Factors (MF ventilated) for Ventilated Compartments ................A4-2 Figure 7. Minimum Safe Compartment Volume for One Extinguisher in UnventiJated Compartments ............................... ...... ....................... ..................A4-4 Figure 8. Fire Extinguisher Performance and Gross Weights ........ ...........................A4-5 Figure 9. Aircraft Volumes and Ventilation .................................................. .....A4-6 iv 0J/14/ 11 AC20-42D Chapter 1. General Information about this Advisory Circular {AC} I . What is the Purpose of this Advisory Circular (AC)? a. We provide guidance for fue-figbting effectiveness, selection, location and mounting ofhand fire extinguishers. b. We establish the halocarbons hydrochlorofluorocarbon (HCFC) Blend B, bydrofluorocarbon (HFC)-227ea, and HFC-236fa as FAA approved replacement agents to Halon 12 I 1 and Halon 1301. c. This AC recommends that you transition to using these new halocarbon clean agents in fire extinguishers kept onboard aircraft and rotorcraft. We explain how to gain certification for halocarbon clean agent extingujshers intended to replace Halon 12 11 hand-held extinguishers. d. This AC recommends that dry chemical, dry powder, and carbon dioxide hand extinguishers, in general. should not be used in aircraft . e. We also explain how to gain Federal Aviation Administration (FAA) certification for replacement agent fire extinguishers, which you may use to comply wjth Title 14 ofthe Code of Federal Regulations (14 CFR) parts 23, 25, 29. 91, 121 , 125, 127, and 135. f. This AC establishes an FAA approved minimum performance standard (MPS) for halon replacement agents wh.ich includes a hidden fire test and a seat fi re/toxicity test. g. This AC recognizes that toxicity ofhalocarbon agents and their decomposition