Police Body Armor Standards and Testing, Vol. I
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Police Body Armor Standards and Testing, Vol. I August 1992 OTA-ISC-534 NTIS order #PB92-216100 Recommended Citation: U.S. Congress, Office of Technology Assessment, Police Body Armor Standards and Testing: Volume I, OTA-ISC-534 (Washington, DC: U.S. Government Printing Office, August 1992). For sale by [he U.S. Government Printing Office Superintendent of Documents, Mail Stop: SSOP, Washington, DC 20402-9328 ISBN 0-16 -037987-3 Foreword For two decades, the number of police officers shot to death each year has been declining while the number of officers shot has been increasing. The decrease in the lethality of shootings is partly attributable to the increase in wearing of bullet-resistant body armor, especially soft, inconspicuous armor designed to be worn full-time. A prospective purchaser can see how much of the body an armor garment covers but cannot see whether it will stop a particular kind of bullet at a particular velocity and protect the wearer from the impact. To provide benchmarks for protection, the National Institute of Justice issued NIJ Standard 0101.03 in 1987. It specifies standard procedures for testing samples of armor. If samples of a model pass, the NIJ or the manufacturer may certify that the model has the type of ballistic resistance for which it was tested. The standard has been controversial since it was issued. This Report describes the origin of the standard, the rationale for particular provisions, and the main points of controversy, which concern acceptable risks, the validity and discrumination of the test, and the reproducibility of results. OTA finds that resolving these controversies will require specifying acceptable risks quantitatively, performing additional research to test validity, and implement- ing a quality-control program. To date, all armor of NIJ-certified models has performed as rated in service-but so has uncertified armor, including armor that would fail the test specified by the standard. This has provoked charges that the NIJ test is too stringent and fails to discriminate some safe armor from unsafe armor. The validity and discrimination of the test are technical issues that are susceptible to scientific analysis—if the NIJ specifies maximum acceptable risks quantita- tively. The Report describes illustrative specifications of acceptable risks and an experimental method for deciding whether the current test, or any proposed alternative, limits the risks as required. It also describes and compares several options for a quality-control program. This assessment was requested by Senator Joseph R. Biden, Jr. (Chairman), Senator Strom Thurmond (Ranking Minority Member), Senator Dennis DeConcini, and Senator Edward M. Kennedy of the Senate Committee on the Judiciary, Congressman John Joseph Moakley, Chairman of the House Rules Committee, and Congressman Edward F. Feighan of the House Committee on the Judiciary and of its Subcommittees on Crime and on Economic and Commercial Law. JOHN H. GIBBONS u Director iii Police Body Armor Standards and Testing Advisory Panel Lester B. Lave, Panel Chair James H. Higgins Professor of Economics Graduate School of Industrial Administration Carnegie-Mellon University George N. Austin, Jr. David C. Hill National Officer President Fraternal Order of Police Fibers Division Engineered Materials Sector Lane Bishop Allied-Signal, Inc. Statistician Center for Applied Mathematics Max Henrion Allied-Signal, Inc. Member of the Technical Staff Rockwell International Science Center Alfred Blumstein Dean and J. Erik Jonsson Professor of Alexander Jason Urban Systems and Operations Research Ballistics Consultant School of Urban and Public Affairs ANITE Group Carnegie-Mellon University Harlin R. McEwen Michael Bowman Chief Vice President and General Manager Ithaca Police Department Fibers Department Isaac Papier E.I. duPont de Nemours & Co., Inc. Managing Engineer Milton Brand Burglary Detection and Signaling Dept. President Underwriters Laboratories, Inc. The Brand Consulting Group Richard Stone James T. Curran President Professor and Dean for Special Programs Point Blank Body Armor, Inc. John Jay College of Criminal Justice Dieter Wachter City University of New York Vice President of High-Performance Fabric Donald R. Dunn Clark-Schwebel Fiberglass Corp. President Robert Wantz H.P. White Laboratory, Inc. President Martin Fackler Personal Protective Armor Association President International Wound Ballistics Association Michael A. Goldfarb General Surgeon Monmouth Medical Center NOTE: OTA appreciates and is grateful for the valuable assistance and thoughtful critiques provided by the advisory panel members. The panel does not, however, necessarily approve, disapprove, or endorse this report. OTA assumes full responsibility for the report and the accuracy of its contents. iv OTA Project Staff—Police Body Armor Standards and Testing Lionel S. Johns, Assistant Director, OTA Energy, Materials, and International Security Division Alan Shaw, International Security and Commerce Program Manager Michael B. Callaham, Project Director Brian McCue, Senior Analyst Jonathan Tucker, Analyst (through May 1991) Administrative Staff Jacqueline Robinson Boykin Office Administrator Louise Staley Administrative Secretary v Acknowledgements OTA gratefully acknowledges the assistance of the following individuals and organizations for their help in supplying information or in reviewing drafts of portions of this report. The individuals and organizations listed do not necessarily approve, disapprove, or endorse this report; OTA assumes full responsibility for the report and the accuracy of its contents. Allied-Signal, Inc. U.S. Department of Commerce Kevin McCarter National Institute of Standards and Technology Sam White Keith Eberhardt Steven A. Young Lawrence K. Eliason Daniel E. Frank Aspen Systems, Inc. John Whidden Marc H. Caplan Patent and Trademark Office Wendy Howe Deborah L. Kyle Candace McIlhenny U.S. Department of Defense Canadian General Standards Board Strategic Defense Initiative Organization Marian L. Gaucher Nicholas Montanarelli E.I. duPont de Nemours and Company, Inc. Department of the Army Thomas E. Bachner, Jr. Ballistics Research Laboratory William Brierly Russell N. Prather Louis H. Miner Chemical Research, Development, and Helen A. Slavin Engineering Center Larry Sturdivan Elgin (IL) Police Department Charles A. Gruber U.S. Department of Justice Bureau of Alcohol, Tobacco, and Firearms General Motors Research Laboratories Daniel Hartnett David C. Viano Federal Bureau of Investigation Hartford (VT) Police Department Bunny Morris Joseph G. Estey David Pisenti Charles Barry Smith Home Office Police Scientific Development Branch National Institute of Justice Eric Brown Paul Cascarano Jaba Associates (Ontario) Charles DeWitt Alan Athey Paul Estaver Point Blank Body Armor, Inc. University of Maryland Gaetan (Tom) J. Dragone Girish Grover Ann Beth Jenkins Second Chance Body Armor, Inc. Ian Twilley Clinton Davis Lisa Hinz Frederick Peter Watkins Lester Shubin vi INTRODUCTION . 1 BACKGROUND . .. 7 Soft Armor and Hard Armor . 7 Summary of NIJ Standard 0101.03 . 7 FINDINGS . .. 13 Benefits of Wearing Armor . 13 Factors Influencing Wearing of Armor . 14 Goals obtesting and Certitfication . .16 Test Procedures . .21 Assuring Quality . 27 UNRESOLVED ISSUES . 27 OPTIONS FOR THE DEPARTMENT OF JUSTICE . 29 Specify Acceptable Risks . .30 Revise NIJ Standard 0101.03 . .32 Assure Quality . 36. Sponsor Research . 38 OTHER POLICY OPTIONS . .39 Expand FTC Activities; Involve OSHA . 39 LEGISLATIVE OPTIONS . .. .40 Fund NIJ-Sponsored Research . 40 BIBLIOGRAPHY . 41 Boxes Box Page A. How Soft Armor Works . .. 2 B. KevlarR and TwaronR . 3 C. SpectraR and Spectra ShieldTM . .. 4 D. Trends in Weapons and Ammunition Used in Assaults on Police . 8 E. Types of Guns . 9 F. ABCs of Ammunition, Bullets, and Cartridges . 10 G. Stringency, Validity, and Reproducibility. 17 H. Statistical Confidence . 18 Figures Figure Page l. Certification That a Model of Armor Complies With the NIJ Standard is Based on Inspection and Testing of Samples Submitted by the Manufacturer . 13 2. Instrumented Ballistic Test Range for Testing Armor as Specified in NIJ Standard 0101.03 . 14 3. Sequence of Aim Points on Each Panel, as Specified in NIJ Standard 0101.03 . 14 4. How Fatal Bullet Wounds in the Torso Would Decrease if the Wear Rate Increased . 14 Contents—Continued Page 5. Wear Rate Versus Temperature-Humidity Index (THI) . 15 6. Wear Rate Versus Month . 15 7. Wear Rate Versus Areal Density of Armor . 16 8. “Reenactment” of a Ballistic Test That Armor Shot in an Assault Could Have Been Subjected To . 22 9. Discrimination of the NIJ Test for Protection From the Impact of Stopped Bullets . 23 10. Shots Per Panel in Actual Assaults . 24 11. Effect of Wetness on Ballistic Resistance of KevlarR Armor . 29 12. Estimates of V50 and V10 Obtained by Logistic Regression . 35 13. Notional Control Chart for Sequential Lot-Acceptance Testing . 37 Tables Table Page 1. Types of Ballistic Resistance Defined by NIJ Standard 0101.03 in Terms of Bullets and Velocities Specified for Testing . 11 2. Tyes of Ballistic Resistance Defined by NIJ Standard 0101.03 in Terms of Guns and Ammunition Against Which Protection is Expected . 12 3. Choices for Safety Goals . ..