Testing of Body
Armor Materials

Phase III

Committee on Testing of Body Armor Materials for Use by the U.S. Army—Phase III

Board on Army Science and Technology
Division on Engineering and Physical Sciences

and

Committee on National Statistics
Division of Behavioral and Social Sciences and Education

NATIONAL RESEARCH COUNCIL
OF THE NATIONAL ACADEMIES

THE NATIONAL ACADEMIES PRESS
Washington, D.C.
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TESTING OF BODY ARMOR MATERIALS - PHASE III Testing of Body Armor Materials Phase III Committee on Testing of Body Armor Materials for Use by the U.S. Army—Phase III Board on Army Science and Technology Division on Engineering and Physical Sciences and Committee on National Statistics Division of Behavioral and Social Sciences and Education

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TESTING OF BODY ARMOR MATERIALS - PHASE III THE NATIONAL ACADEMIES PRESS 500 Fifth Street, NW Washington, DC 20001 NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance. This material is based on work supported by the National Science Foundation under Grant No. SES- 0453930, Amendment #012. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. International Standard Book Number ISBN-13: 978-309-25599-8 International Standard Book Number ISBN-10: 0-309-25599-6 Limited copies of this report are available from: Additional copies are available from: Board on Army Science and Technology The National Academies Press National Research Council 500 Fifth Street, NW 500 Fifth Street, NW, Room 940 Keck 360 Washington, DC 20001 Washington, DC 20001 (202) 334-3118 (800) 624-6242 or (202) 334-3313 http://www.nap.edu Copyright 2012 by the National Academy of Sciences. All rights reserved. Printed in the United States of America

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TESTING OF BODY ARMOR MATERIALS - PHASE III The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Ralph J. Cicerone is president of the National Academy of Sciences. The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. Charles M. Vest is president of the National Academy of Engineering. The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Harvey V. Fineberg is president of the Institute of Medicine. The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy’s purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Ralph J. Cicerone and Dr. Charles M. Vest are chair and vice chair, respectively, of the National Research Council. www.national-academies.org

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TESTING OF BODY ARMOR MATERIALS - PHASE III COMMITTEE ON THE TESTING OF BODY ARMOR FOR THE U.S. ARMY – PHASE III LARRY G. LEHOWICZ, MG, U.S. Army (retired), Chair, Quantum Research International, Arlington, Virginia CAMERON R. BASS, Duke University, Durham, North Carolina THOMAS F. BUDINGER, E.O., NAE/IOM,1 Lawrence Berkeley National Laboratory, Berkeley, California MORTON M. DENN, NAE, City College of the City University of New York WILLIAM G. FAHRENHOLTZ, Missouri University of Science and Technology, Rolla RONALD D. FRICKER, JR., Naval Postgraduate School, Monterey, California YOGENDRA M. GUPTA, Washington State University, Pullman DENNIS K. KILLINGER, University of South Florida, Tampa VLADIMIR B. MARKOV, Advanced Systems and Technologies, Inc., Irvine, California JAMES D. McGUFFIN-CAWLEY, Case Western Reserve University, Cleveland, Ohio RUSSELL N. PRATHER, Survice Engineering Company, Bel Air, Maryland SHELDON WIEDERHORN, NAE, National Institute of Standards and Technology, Gaithersburg, Maryland ALYSON GABBARD WILSON, Institute for Defense Analyses, Alexandria, Virginia Staff BRUCE A. BRAUN, Director, Board on Army Science and Technology ROBERT LOVE, Study Director HARRISON T. PANNELLA, Senior Program Officer NIA D. JOHNSON, Senior Research Associate, Board on Army Science and Technology JAMES MYSKA, Senior Research Associate, Board on Army Science and Technology DEANNA P. SPARGER, Program Administrative Coordinator, Board on Army Science and Technology ANN LARROW, Research Assistant JOSEPH PALMER, Senior Program Assistant ALICE WILLIAMS, Senior Program Assistant (until September 10, 2010) CONSTANCE CITRO, Director, Committee on National Statistics DENNIS CHAMOT, Acting Director, National Materials Advisory Board JAMES P. McGEE, Director, Laboratory Assessments Board 1 NAE/IOM, National Academy of Engineering/Institute of Medicine. iv

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TESTING OF BODY ARMOR MATERIALS - PHASE III BOARD ON ARMY SCIENCE AND TECHNOLOGY ALAN H. EPSTEIN, Chair, Pratt & Whitney, East Hartford, Connecticut DAVID M. MADDOX, Vice Chair, Independent Consultant, Arlington, Virginia DUANE ADAMS, Independent Consultant, Arlington, Virginia ILESANMI ADESIDA, University of Illinois at Urbana-Champaign MARY E. BOYCE, Massachusetts Institute of Technology, Cambridge EDWARD C. BRADY, Strategic Perspectives, Inc., Fort Lauderdale, Florida W. PETER CHERRY, Independent Consultant, Ann Arbor, Michigan EARL H. DOWELL, Duke University, Durham, North Carolina JULIA D. ERDLEY, Pennsylvania State University, State College LESTER A. FOSTER, Electronic Warfare Associates, Herndon, Virginia JAMES A. FREEBERSYSER, BBN Technology, St. Louis Park, Minnesota RONALD P. FUCHS, Independent Consultant, Seattle, Washington W. HARVEY GRAY, Independent Consultant, Oak Ridge, Tennessee JOHN J. HAMMOND, Independent Consultant, Fairfax, Virginia RANDALL W. HILL, JR., University of Southern California Institute for Creative Technologies, Playa Vista JOHN W. HUTCHINSON, Harvard University, Cambridge, Massachusetts MARY JANE IRWIN, Pennsylvania State University, University Park ROBIN L. KEESEE, Independent Consultant, Fairfax, Virginia ELLIOT D. KIEFF, Channing Laboratory, Harvard University, Boston, Massachusetts WILLIAM L. MELVIN, Georgia Tech Research Institute, Smyrna ROBIN MURPHY, Texas A&M University, College Station SCOTT PARAZYNSKI, University of Texas Medical Branch, Galveston RICHARD R. PAUL, Independent Consultant, Bellevue, Washington JEAN D. REED, Independent Consultant, Arlington, Virginia LEON E. SALOMON, Independent Consultant, Gulfport, Florida JONATHAN M. SMITH, University of Pennsylvania, Philadelphia MARK J.T. SMITH, Purdue University, West Lafayette, Indiana MICHAEL A. STROSCIO, University of Illinois, Chicago DAVID A. TIRRELL, California Institute of Technology, Pasadena JOSEPH YAKOVAC, JVM LLC, Hampton, Virginia Staff BRUCE A. BRAUN, Director CHRIS JONES, Financial Manager DEANNA P. SPARGER, Program Administrative Coordinator v

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TESTING OF BODY ARMOR MATERIALS - PHASE III COMMITTEE ON NATIONAL STATISTICS LAWRENCE D. BROWN, Chair, Department of Statistics, Wharton School, University of Pennsylvania JOHN M. ABOWD, School of Industrial and Labor Relations, Cornell University DAVID CARD, Department of Economics, University of California, Berkeley ALICIA CARRIQUIRY, Department of Statistics, Iowa State University CONSTANTINE GATSONIS, Center for Statistical Sciences, Brown University JAMES S. HOUSE, Survey Research Center, Institute for Social Research, University of Michigan MICHAEL HOUT, Survey Research Center, University of California, Berkeley SALLIE ANN KELLER, University of Waterloo, Ontario, Canada LISA LYNCH, Heller School for Social Policy and Management, Brandeis University SALLY C. MORTON, Department of Biostatistics, Graduate School of Public Health, University of Pittsburgh RUTH D. PETERSON, Criminal Justice Research Center, Ohio State University EDWARD H. SHORTLIFFE, Columbia University and Arizona State University HAL STERN, Donald Bren School of Information and Computer Sciences, University of California, Irvine JOHN H. THOMPSON, National Opinion Research Center, University of Chicago ROGER TOURANGEAU, Westat, Rockville, Maryland Staff CONSTANCE CITRO, Senior Board Director JULIA KISA SHAKEER, Financial Associate JACQUI SOVDE, Program Associate vi

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TESTING OF BODY ARMOR MATERIALS - PHASE III Preface This report is the final volume of a three-phase study commissioned by the Director of Operational Test and Evaluation (DOT&E) of the Department of Defense (DoD) to assist in addressing shortcomings that had been reported by the Government Accountability Office (GAO) and the DoD Inspector General in DoD’s body armor testing process. Independent committees were empanelled for the three study phases. Each committee produced an independent report, although this final Phase III report builds on the results of the letter reports delivered in Phases I and II, both of which provided findings and recommendations on key issues that required near-term resolution by DOT&E. The study was conducted under the auspices of the National Research Council (NRC) Board on Army Science and Technology (BAST) and Committee on National Statistics. The Phase I letter report, released in January 2010, addressed the adequacy of laser instrumentation for evaluating ballistics tests in clay material. The Phase II report, released in May 2010, focused on the behavior of ballistics clay used as a recording medium during live-fire testing. The Phase III committee had more time for meetings and data gathering than the two previous committees and was able to use the substantial amount of data collected throughout the entire study. As a result the committee was able to delve more deeply into all available data than had been possible in the earlier phases of the effort. This Phase III report provides a wide range of recommendations designed to help enable the entire body armor community to utilize an effective testing process leading to fielding the best equipment possible that meets performance specifications while reducing the weight burden placed on soldiers in training or combat. The Phase III committee deserves special thanks for its hard work. Several committee members went well beyond the norm in interviewing numerous experts, assessing the pertinent issues, and developing recommendations to address the many demands of the committee’s statement of task. In particular, committee member Thomas Budinger deserves special credit for leading the Phase III ad hoc instrumentation committee subgroup that produced a thoughtful review of the data and information related to instrumentation. The committee is also grateful to the many DoD, Army, Marine Corps, industry, and contractor personnel engaged in body armor testing for the useful information they provided. vii

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TESTING OF BODY ARMOR MATERIALS - PHASE III Finally, the committee also greatly appreciates the support and assistance of the NRC staff members who assisted the committee in its fact-finding activities and in the production of the three separate committee reports. In particular, thanks are due to the BAST staff, principally Bruce Braun, Margaret Novack, and Robert Love, who ably facilitated the committee’s work. Larry Lehowicz, Chair Committee on Testing of Body Armor Materials for Use by the U.S. Army—Phase III viii

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TESTING OF BODY ARMOR MATERIALS - PHASE III Acknowledgment of Reviewers This report has been reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise, in accordance with procedures approved by the National Research Council’s Report Review Committee. The purpose of this independent review is to provide candid and critical comments that will assist the institution in making its published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We wish to thank the following individuals for their review of this report: Morris E. Fine (NAE), Northwestern University John S. Foster, Jr. (NAE), GKN Aerospace Transparency Systems David Higdon, Los Alamos National Laboratory Peter Matic, Naval Research Laboratory Erik Novak, Veeco Instruments, Henry Smith (NAE), Massachusetts Institute of Technology Leslie J. Struble, University of Illinois Stephen F. Vatner, New Jersey Medical School Emmanuel Yashchin, IBM Watson Research Center Laurence R. Young (NAE/IOM), Massachusetts Institute of Technology Although the reviewers listed above have provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations, nor did they see the final draft of the report before its release. The review of this report was overseen by Lawrence D. Brown, NAS, Wharton School, University of Pennsylvania, and Arthur H. Heuer, NAE, Case Western Reserve University. Appointed by the National Research Council, they were responsible for making certain that an independent examination of this report was carried out in accordance with institutional procedures and that all review comments were carefully considered. Responsibility for the final content of this report rests entirely with the authoring committee and the institution. ix

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TESTING OF BODY ARMOR MATERIALS - PHASE III x

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TESTING OF BODY ARMOR MATERIALS - PHASE III Contents SUMMARY 1 1 INTRODUCTION 20 Background, 20 Study Tasks, 20 Study Context, 22 Study Implementation, 22 Report Organization, 23 References, 24 2 OVERVIEW OF BODY ARMOR 25 Background, 25 Ceramic Plates in Body Armor, 26 Fiber and Resin Composites in Helmets, 26 Survivability vs. Mobility, 27 Medical Study Basis for Testing Body Armor, 27 Body Armor Testing Process, 28 Body Armor Testing Range, 31 Government Accountability Office Report, 32 References, 33 3 HISTORICAL BASIS FOR CURRENT BODY ARMOR TESTING 34 Background, 34 Evolution of Clay Usage, 38 High-Energy Threats, 41 Rifle Threats for Hard Body Armors, 42 Work Performed after the Prather Study, 42 Current Standard, 44 References, 44 4 CLAY AND BACKING MATERIALS 46 Use of Backing Material as a Recording Medium, 46 Characteristics and Properties of RP #1, 51 Behavior in Testing, 51 Influence of Structure on Properties of Oil-Base Modeling Clay, 63 Short-Term Development of an Interim Standard Clay Formulation for Ballistic Testing, 69 Conditioning and Handling of Clay, 71 Calibration Drop Test, 74 Alternative Backing Materials and Systems, 76 xi

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TESTING OF BODY ARMOR MATERIALS - PHASE III Medium-Term and Long-Term Replacements for Modeling Clay, 76 Electronic Recording Systems, 78 Roadmap for Improving the Testing Process, 79 Near-Term Actions, 81 Medium-Term Research Needs, 85 Long-Term Goal, 88 References, 88 5 INSTRUMENTATION AND PROCEDURES FOR MEASURING 92 AN INDENT IN A CLAY BACKING MATERIAL Conceptual Steps Toward Improvements in the Measurement of BFD, 92 Step One, 92 Step Two, 93 Step Three, 93 Step Four, 93 Steps Five and Six, 94 Instrumentation Performance Based on Statistical Analysis, 94 Overview of Current Instrumentation and Measurements, 96 Coordinate Measuring Machine, 96 Digital Caliper, 96 Faro System, 97 BFD Measuring Procedures, 99 Human Operator Considerations, 99 Compensating for Offset between the Point of Aim and the Deepest Indent, 101 Variability (Noise) in the Overall Testing Process, 101 Need for a Stand-Alone BFD Artifact or Standard Model for InterorganizationVerification, 103 Characteristics of a “Best Utility” Measuring Instrument, 104 References, 106 6 STATISTICAL CONSIDERATIONS IN BODY ARMOR TESTING 107 Introduction, 107 Statistically Principled Testing, 107 Uncertainty and Variation Drive Overdesign, 108 Key Test Protocol Design Requirements, 109 Background, 111 Historical First Article Testing Protocols, 111 DOT&E Protocol for Body Armor FAT, 113 Test Protocol Assumptions, 119 Lot Acceptance Testing, 123 Protocol Design Trade-offs and Comparisons, 128 Recommendations, 132 References, 135 xii

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TESTING OF BODY ARMOR MATERIALS - PHASE III 7 HELMET TESTING 137 Ballistic Helmet Test Methodolgies, 137 Injury Modes, 139 Existing Human Injury Criteria, 140 Head Injury from Ballistic Impact, 142 Neck Injury, 143 Helmet Design and Suspension Systems, 145 Existing Helmet Test Methodologies, 146 NIJ Standard 0106.01, 148 Army Clay Head Form, 150 Testing Standards, 151 Test Procedures, 152 H.P. White Laboratory Test Procedure, 157 Peepsite Head Form, 160 UVA Head Form, 163 BLS Head Form, 164 References, 165 8 MEDICAL BASIS FOR FUTURE BODY ARMOR 169 TESTING Thoracic Ballistic Test Methodologies, 169 Introduction to Behind Armor Blunt Trauma, 169 Ergonomics of Body Armor, 173 Injury Biomechanics, 173 Injury Criteria and Experimentation, 177 Blast Injury Criteria and Blastlike Mechanisms, 183 Low-Rate Blunt Trauma Mechanisms, 185 Human Epidemiology for Battlefield BABT, 185 Injury Scales, 186 Current Epidemiology for Battlefield/Law Enforcement BABT, 191 Large Animal Experiments for Behind-Armor Blunt Trauma, 191 Potential Adverse Effects of Body Armor in Blast Exposures, 206 Cadaveric Experiments for Behind-Armor Blunt Trauma, 209 Rationale for Large-Animal, Live-Fire Experiments, 212 Instrumented Determination of Backface Deformation—Research Directions, 213 Bulk Tissue Simulants, 215 Instrumented Response Elements, 215 Instrumented Detailed Anatomical Surrogates, 221 Developmental Testing Requirements, 225 Medical Research Needs, 229 Near-Term Actions, 229 Medium-Term Actions, 230 References, 231 xiii

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TESTING OF BODY ARMOR MATERIALS - PHASE III 9 FUTURE IMPROVEMENTS IN TESTING METHODOLOGY 240 Building on the Prather Study, 240 Synopsis of Near-Term Improvements, 241 Linking Medical Research Data to Product Testing Criteria, 243 Dynamics and Measurement of Behind-Armor Forces, 244 Synchronizing the Stakeholders, 248 Military and Law Enforcement Personnel, 249 Technologists, 250 Medical Researchers, 250 Testers—Developmental and Operational, 250 Aligning Stakeholders, 251 Establishing National Standards, 252 References, 254 APPENDIXES A Biographical Sketches of Committee Members 257 B Committee Meetings 264 C Additional Phase III Tasks 268 D Report Sections Cross-Referenced to the Statement of Task 269 E Ballistic Body Armor Insert Composition and Defeat Mechanisms 272 F Committee Responses to the Government Accountability 274 Office Report G Determining the Necessary Level of Precision for 280 Body Armor Testing H Statistical Tolerance Bounds 299 I Analytical Approaches for Comparing Test Protocols 302 J Contemporary Methods for Assessing Behind-Armor 305 Blunt Trauma in Live Animals K Phase I Findings 316 L Phase II Recommendations 317 M Estimating the Accuracy and Precision of the 323 Digital Caliper and Faro Laser xiv

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TESTING OF BODY ARMOR MATERIALS - PHASE III Tables, Figures, and Boxes TABLES 3-1 Strengths and Weaknesses of the Prather Methodology, 45 4-1 Elastic Recovery in Modified Charpy Testing of Oil-Based Modeling Clay, 49 6-1 60-Plate Protocol, 115 6-2 Proposed FAT Standards, 117 6-3 Proposed LAT Standards, 124 6-4 Risk Comparisons for Probability of Complete Penetration, 129 7-1 Characteristics of Test Rounds from NIJ Standard-0106.01, 149 7-2 H.P. White Laboratory Test Procedure, 158 7-3 Helmet Test Matrix, 161 8-1 Muzzle Parameters for Various Types of Rounds, 170 8-2 Energy/Momentum for Various Typical Thoracic Trauma Situations, 171 8-3 Description of Levels of Thoracic Trauma, 186 8-4 Combat Effectiveness vs. Levels of Thoracic Trauma, 187 8-5 Bullet Specifications and Injury Outcome, 194 9-1 Strengths and Weaknesses of the Prather Methodology, 241 FIGURES S-1 Road map showing suggested near-term actions, medium-term research needs, and a long-term goal to develop a more consistent backing material and a more reliable process for evaluating hard armor, 8 S-2 Road map showing suggested near-term and medium-term research needs, and a long-term goal to provide the fundamental medical basis for injury risk assessment behind helmets and hard body armor, 17 2-1 The clay appliqué applied to the clay box, 29 2-2 Surface of the BFD as measured by a laser scanning system, 30 2-3 The body armor test range at ATC, 32 3-1 Overview of development of Prather clay methodology, 35 xv

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TESTING OF BODY ARMOR MATERIALS - PHASE III 3-2 Blunt deformation profiles into gelatin using seven-ply K29 armor samples mounted on gelatin and tested with the .38-cal LRN bullet at 213 m/sec (800 ft/sec), 37 3-3 Deformation depth vs. time of candidate materials in a goat thorax using a blunt impactor at 55 m/sec, 39 3-4 Logistic regression model of death vs. deformation for blunt impact into goat chests, 39 3-5 Logistic regression model of death vs. deformation for blunt impact into clay using deformation response into goat chests and clay, 41 3-6 Clay deformation behind hard armor with rifle round threats, 42 3-7 Variation of clay penetration depth with velocity for behind-body armor deformation (7.62-mm NATO round, UHMWPE body armor), 43 3-8 Variation of clay penetration area with velocity for behind-body armor deformation (7.62-mm NATO round, UHMWPE body armor), 43 4-1 A schematic illustration of the stress-strain curves for two idealized solids, 47 4-2 A contour gage in use, 48 4-3 Column drop test as performed at ATC, 53 4-4 The results of drop tests on clay boxes allowed to naturally cool from 40°C in a room at normal room temperature (roughly 23°C), 55 4-5 Drop test results using the standard Army right-circular cylinder with a solid hemispherical cap (44.5 mm [1.75 in.] in diameter with a mass of 1 kg [2.2 lb]), a similar non-standard double-length cylinder of the same diameter with the same type of hemispherical cap, and sphere with the diameter specified in the National Institute of Justice Standard (NIJ), 63.5 mm (2.5 in.) in diameter, 56 4-6 Spatial pattern used in a series of experiments to determine the effect of position on the size of the cavity produced during a drop test, 57 4-7 Illustrative results from a study on the effect of radial position on depth of penetration during a drop calibration test, 58 4-8 A clay box used for .32-cal rubber sting ball testing, 61 4-9 Results of sting ball experiments with projectiles ranging from 55 m/sec (180 ft/sec) to 168 m/sec (550 ft/sec), 62 A schematic illustration of the “thixotropic cycle” of a 4-10 two-phase system, 65 4-11 Optical micrographs of a three-dimensional network of spherical latex particles, 66 4-12 Road map showing suggested near-term actions, medium-term research needs, and a long-term goal to develop a more consistent backing material and a more reliable process for evaluating hard armor, 81 5-1 Digital calipers used in armor testing, 97 5-2 Faro Quantum laser scan arm, 98 6-1 USSOCOM FAT shot pattern, 113 xvi

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TESTING OF BODY ARMOR MATERIALS - PHASE III 6-2 Plot of the actual coverage level achieved by a lower confidence bound calculated according to the Clopper-Pearson method for n = 60 and various Pr(nP), 122 6-3 Probability a lot passes LAT first shot requirements for Pr(nP) for the S-4 and S-3 inspection levels for various lot sizes and an AQL of 4 percent, 126 6-4 Probability a lot passes LAT second shot requirements for Pr(nP) for the S-4 and S-3 inspection levels for various lot sizes and an AQL of 4 percent, 127 Plot of the manufacturer’s risk for various Pr(nP) under the DOT&E 6-5 protocol, 130 6-6 Risk comparisons for BFD assuming in the left plot that the manufacturer’s true mean BFD is 38 mm and in the right plot is 40 mm; the associated fraction of variation is shown on the x-axis, 131 7-1 Effective momentum of high-rate ballistic impacts at muzzle velocity and low-rate football impact, 138 7-2 Ballistic impact injury timescales, 138 7-3 Likeness of a deformed personnel armor system for ground troops helmet, 139 7-4 Cadaver instrumentation overview, 142 7-5 Neck injury assessment value for 9-mm FMJ test round at various velocities into helmeted human cadavers, 144 7-6 Residual head/neck velocity from momentum transfer to the helmet/head system, 145 7-7 Impact energy for helmet standards, 147 7-8 Ballistic (high-rate) skull fracture data vs. impact injury criteria for typical blunt injury, 147 7-9 NIJ sagittal penetration head form, 148 7-10 Army clay head form, 150 7-11 ATC head form with clay, 153 7-12 Head form clay conditioning by analogy, 154 7-13 Test impact locations, 156 7-14 Test frame, 156 7-15 H.P. White head form, 159 7-16 Peepsite head forms: different head forms for different shot directions, 160 7-17 Left, UVA head form; right, risk assessment, 163 7-18 BLS head form, 164 7-19 Arrangement and dimensions of load cells in the BLS head form, 165 8-1 Initial energy and momentum for ballistics and other blunt impacts, 171 8-2 Superimposed high speed X-rays of the initial shock wave and deformation of the thorax during a 7.62 mm projectile live-fire test in a pig protected by hard body armor, 172 8-3 Development of surrogate injury model, 175 8-4 Volunteer experimentation, 177 xvii

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TESTING OF BODY ARMOR MATERIALS - PHASE III 8-5 Human upper torso, 179 8-6 Threshold pressures and exposure times needed to damage drosophila larvae using various loading devices, 180 8-7 Threshold damage for various tissues, 181 8-8 ASII values versus peak inward chest wall velocity, 183 8-9 Overpressure/duration blast injury criteria, 184 8-10 Kinetic energy vs. injury severity, 188 8-11 Time of delivery of wounded to the CMH (average 1983-1984), 189 8-12 Severity of wounds for patients delivered to the CMH (average 1983- 1984), 190 8-13 Lateral dog thorax impacted by nonpenetrating missiles, 192 8-14 Impact energy (scaled to a 75 kg man) vs. increased lung mass, 193 8-15 Body armor for Oksbøl trials, 196 8-16 Average first and second peak pressure, Oksbøl trials, 197 8-17 Average postmortem lung mass, Oksbøl trials, 198 8-18 Oksbøl first peak on Bowen curve, 199 8-19 Animal fatalities during monitoring period, 201 8-20 BABT flash X-ray, 202 8-21 Relationship between area of lung surface contusion and maximum back- face deformation of body armor, 202 8-22 Relationship between area of lung surface contusion and pressure 6 cm from point of impact, 203 8-23 Examples of BABT assessment devices and methodologies, 214 8-24 DERA BABT simulator displacement sensor system, 216 8-25 DERA tissue viscoelastic stimulant concept as described by Mirzeabassov et al., 2000, 218 8-26 Hybrid III 50th percentile male dummy, 219 8-27 ATM with mounted body armor; ATM instrumented response element with padding; oblique view within torso, 220 8-28 Human CT scan; finite-element model, 221 8-29 AUSMAN upper torso, 222 8-30 AUSMAN thorax with body armor in place, prior to testing, 223 8-31 Road map showing suggested near-term and medium-term research needs, and a long-term goal to provide the fundamental medical basis for injury risk assessment behind helmets and hard body armor, 228 9-1 Road map showing suggested near-term actions, medium-term research needs, and a long-term goal to develop a more consistent backing material and a more reliable process for evaluating hard armor, 242 9-2 Flow chart showing suggested near-term and mid-term research needs, and a long-term goal to provide the fundamental medical basis for injury risk assessment behind helmets and hard body armor, 243 9-3 Schematic of conceptual approach used by both testers and researchers showing a projectile impacting normally onto hard body armor (A), soft body armor (B), and a recording medium surrogate for a human body (C), 244 xviii

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TESTING OF BODY ARMOR MATERIALS - PHASE III 9-4 Schematic of the dynamic measurement method, 246 9-5 Schematic of stakeholder relationships, 249 G-1 Plot of normally distributed BFDs from a design that just meets the 90 % upper tolerance limit requirement with pop = 42.7 mm and pop = 1 mm, 281 G-2 The consequence of measurement error on the apparent depths of BFDs, 282 G-3 The relationship between measurement error and the overall variance in armor testing, 286 G-4 How improving the performance of armor relates to the probability of passing FAT assuming a lot size of 60 plates, 289 G-5 Plot of the difference between the two FAT failure curves, 291 G-6 Photograph, laser scan, and cross section of cavity in RP #1 produced by armor testing, 293 G-7 Digital calipers used in armor testing, 294 G-8 Two images of typical BFD cavities in RP #1 produced by the Faro laser scanner, 295 G-9 The probability a manufacturer will pass the first article, first shot BFD test (solid line) for various population mean BFD levels () versus the probability that a plate will have a BFD greater than 50 mm from the same population (dotted line), 297 H-1 Ninety-fifth quintile distribution, 300 J-1 Comprehensive protocol for live-animal live-fire tests, 306 M-1 Plot of the paired BFD measurements made by ATC, 324 M-2 Plot of the paired BFD measurements made by Chesapeake Testing, 324 M-3 Absolute value of offsets for caliper measurements from Realistic Clay III, 330 BOXES S-1 Statement of Task, 2 1-1 Statement of Task, 21 L-1 Phase II Recommendations to Improve Body Armor Testing, 321 xix

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TESTING OF BODY ARMOR MATERIALS - PHASE III Acronyms and Abbreviations AIS abbreviated injury scale AP armor piercing AQL acceptance quality level ARDS adult respiratory distress syndrome ARL U.S. Army Research Laboratory ASTM American Society of Testing and Materials ATC U.S. Army Aberdeen Test Center ATD anthropometric test device ATM anthropomorphic test module BABT behind-armor blunt trauma BFD backface deformation BLS ballistic load sensing CMH central military hospital CMM co-ordinate measuring machine DAI diffuse axonal injury DERA Defense Evaluation and Research Agency DGA Délégation Générale pour L'Armement DoD Department of Defense DOT&E Office of the Director, Operational Test and Evaluation DREV Defense Research Establishment Valcartier ECG electrocardiogram ESAPI enhanced small arms protective insert FAT first article testing FMJ full metal jacket GAO Government Accountability Office HIC head injury criteria IG Inspector General ISS injury severity score kPa kilopascal xxi

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TESTING OF BODY ARMOR MATERIALS - PHASE III LAT lot acceptance testing LRN lead round nose MPa megapascal NATO North Atlantic Treaty Organization NIJ National Institute of Justice NIST National Institute of Standards and Technology NRC National Research Council PEO-S U.S. Army Program Executive Office Soldier RCC right circular cylinder RP #1 Roma Plastilina #1 TAB trauma-attenuating backing TBI traumatic brain injury TOP test operating procedure UHMWPE ultra-high molecular weight polyethylene USSOCOM United States Special Operations Command UVA University of Virginia XSAPI X Small Arms Protective Inserts xxii