Evaluation of the 1999-2003 Head Impact Upgrade of FMVSS No. 201 Upper-Interior Components
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DOT HS 811 538 November 2011 Evaluation of the 1999-2003 Head Impact Upgrade of FMVSS No. 201 Upper-Interior Components Effectiveness of Energy-Absorbing Materials Without Head-Protection Air Bags DISCLAIMER This publication is distributed by the U.S. Department of Transportation, National Highway Traffic Safety Administration, in the interest of information exchange. The opinions, findings, and conclusions expressed in this publication are those of the authors and not necessarily those of the Department of Transportation or the National Highway Traffic Safety Administration. The United States Government assumes no liability for its contents or use thereof. If trade names, manufacturers’ names, or specific products are mentioned, it is because they are considered essential to the object of the publication and should not be construed as an endorsement. The United States Government does not endorse products or manufacturers. Suggested APA Format Reference: Kahane, C. J. (2011, November). Evaluation of the 1999-2003 head impact upgrade of FMVSS No. 201 – Upper-interior components: Effectiveness of energy-absorbing materials without head- protection air bags. (Report No. DOT HS 811 538). Washington, DC: National Highway Traffic Safety Administration. Technical Report Documentation Page 1. Report No. 2. Government Accession No. 3. Recipient’s Catalog No. DOT HS 811 538 4. Title and Subtitle 5. Report Date Evaluation of the 1999-2003 Head Impact Upgrade of FMVSS No. November 2011 201 – Upper-Interior Components: Effectiveness of Energy- 6. Performing Organization Code Absorbing Materials Without Head-Protection Air Bags 7. Author(s) 8. Performing Organization Report No. Charles J. Kahane, Ph.D. 9. Performing Organization Name and Address 10. Work Unit No. (TRAIS) Office of Vehicle Safety National Highway Traffic Safety Administration 11. Contract or Grant No. Washington, DC 20590 12. Sponsoring Agency Name and Address 13. Type of Report and Period Covered National Highway Traffic Safety Administration NHTSA Technical Report 1200 New Jersey Avenue SE. 14. Sponsoring Agency Code Washington, DC 20590 15. Supplementary Notes 16. Abstract Federal Motor Vehicle Safety Standard (FMVSS) No. 201 – Occupant Protection in Interior Impact – was upgraded in 1995, with a 1998-2003 phase-in, to reduce occupants’ risk of head injury from contact with a vehicle’s upper interior, including its pillars, roof headers and side rails, and the upper roof. Initially, energy-absorbing materials alone were used to meet the standard. NHTSA statistically analyzed the effect of these materials on head injuries due to upper-interior contact in cars and light trucks in the Crashworthiness Data System of the National Automotive Sampling System for 1995-2009 and the effect on head injuries in fatal crashes in the Fatality Analysis Reporting System – Multiple Cause of Death files for 1999-2007. FMVSS No. 201 without head-protection air bags reduces AIS 4-to-6 head injuries due to contact with upper-interior components by an estimated 24 percent (95% confidence bounds, 11 to 35%), based on the average of the analysis results for the two databases. That is equivalent to a 4.3-percent reduction of overall fatality risk (confidence bounds 2.0 to 6.2%). When all vehicles on the road meet FMVSS No. 201, it will save an estimated 1,087 to 1,329 lives per year. At a cost of $25.52 (in 2010 dollars) over the life of a vehicle, that amounts to an annual cost, depending on new-vehicle sales, ranging from $301 to $424 million for certifying all new vehicles to FMVSS No. 201. It is a very cost-effective regulation, costing less than $1 million per life saved. 17. Key Words 18. Distribution Statement NHTSA; NASS; CDS; FARS; MCOD; FMVSS; Document is available to the public from the HIC; crashworthiness; concussion; A-pillar; B- National Technical Information Service pillar; head impact; Rao-Scott chi-square www.ntis.gov 19. Security Classif. (Of this report) 20. Security Classif. (Of this page) 21. No. of Pages 22. Price Unclassified Unclassified 122 Form DOT F 1700.7 (8-72) Reproduction of completed page authorized i TABLE OF CONTENTS List of abbreviations .................................................................................................................... iii Executive summary ....................................................................................................................... v 1. Head protection in impacts with a vehicle’s upper interior ................................................. 1 1.1 The problem: head injuries due to upper-interior contact ........................................... 1 1.2 The head-injury protection upgrade for FMVSS No. 201 .......................................... 9 1.3 In what ways were vehicles modified? ..................................................................... 10 1.4 HIC test results before and after FMVSS No. 201 ................................................... 17 1.5 Fatality reduction by head-protection air bags in side impacts ................................. 19 2. Effect of FMVSS No. 201 on AIS 3-to-6 head injuries from upper-interior sources: analyses of 1995-2009 CDS data ....................................................................................... 23 2.0 Summary ................................................................................................................... 23 2.1 A database of AIS 3-to-6 injuries before and after FMVSS No. 201 ....................... 23 2.2 Overall reduction of AIS 3-to-6 head injuries from upper-interior sources ............. 26 2.3 Effect on AIS 4 to 6 for specific impact, vehicle, occupant, and injury types ......... 29 2.4 Effect on AIS 3 to 6 for specific impact, vehicle, occupant, and injury types ......... 33 3. Effect of FMVSS No. 201 on head injuries in fatal crashes: analyses of 1999-2007 FARS-MCOD data............................................................................................................. 37 3.0 Summary ................................................................................................................... 37 3.1 Injuries contributing to occupant fatalities, before and after FMVSS No. 201 ........ 37 3.2 Overall reduction of head injuries............................................................................. 41 3.3 Belted versus unrestrained occupants ....................................................................... 43 3.4 Effect for specific impact, vehicle, and occupant types ............................................ 45 4. Discussion: best effectiveness estimate, benefits, and costs .............................................. 48 4.0 Summary ................................................................................................................... 48 4.1 Best effectiveness estimate and its confidence bounds............................................. 48 4.2 Effect on fatalities ..................................................................................................... 49 4.3 Lives saved and potentially savable by FMVSS No. 201 in CY 2004-2009 ............ 50 4.4 Cost of FMVSS No. 201; cost per life saved ............................................................ 54 4.5 Upper-interior head injuries after FMVSS No. 201/head-protection air bags .......... 57 Appendix A: Initial model year of FMVSS No. 201 certification: makes and models produced in 1999-2003 ....................................................................................................... 60 Appendix B: Listing and classification of ICD-10 S and T codes ........................................... 65 Appendix C: Make-model groups for evaluating FMVSS No. 201: model-year ranges included in the FARS-MCOD analyses .............................................................. 74 ii LIST OF ABBREVIATIONS AIS Abbreviated Injury Scale BEA Bureau of Economic Analysis, U.S. Department of Commerce BMW Bayerische Motoren Werke CAC Certified advanced compliant air bag CDC Centers for Disease Control and Prevention, U.S. Department of Health and Human Services CDS Crashworthiness Data System of NASS CG Car group, vehicle group (from NHTSA’s VIN analysis programs) CY Calendar year DEFF Design effect DOT United States Department of Transportation EIA Energy Information Administration, U.S. Department of Energy ESC Electronic stability control FARS Fatality Analysis Reporting System, a census of fatal crashes in the United States since 1975 FMH Free-motion headform FMVSS Federal Motor Vehicle Safety Standard FRIA Final Regulatory Impact Analysis GAD General area of damage GDP Gross domestic product GMC General Motors Corporation GVWR Gross vehicle weight rating, specified by the manufacturer, equals the vehicle’s curb weight plus maximum recommended loading HIC Head Injury Criterion ICD International Classification of Diseases iii ICD-10 International Classification of Diseases, 10th revision LTV Light trucks and vans, includes pickup trucks, SUVs, minivans, and full-size vans LWB Long wheelbase MCOD Multiple cause of death file, a part of FARS MM2 Make-model code (from NHTSA’s VIN analysis programs) mph Miles per hour MY Model year NASS National Automotive Sampling System, a probability sample of police- reported crashes in the United States since 1979, investigated in detail NCHS National Center for Health Statistics NHTSA National Highway Traffic Safety Administration, U.S. Department of Transportation NPRM Notice of Proposed Rulemaking NPV Net present value PSU Primary sampling unit RATWGT [Inverse