DOCUMENT RESUME ED 461 910 EA 028 055 TITLE Crashworthiness of Small Poststandard School Buses: Safety Study. INSTITUTION National Transportation Safety Board (DOT), Washington, DC. REPORT NO NTSB-SS-89/02 PUB DATE 1989-10-11 NOTE 243p. PUB TYPE Reports - Evaluative (142) EDRS PRICE MF01/PC10 Plus Postage. DESCRIPTORS Accidents; *Bus Transportation; *Design Requirements; Elementary Secondary Education; Federal Regulation; Injuries; *School Buses; *School Safety; *Standards; Student Transportation ABSTRACT In 1977, a series of Federal Motor Vehicle Safety Standards (FMVSS) for school buses became effective, mandating different performance standards for school buses compared to other buses. Because data on the crash performance of school buses built to these standards were lacking, the National Transportation Safety Board conducted a series of in-depth accident investigations from 1984 to 1988. The study sought to determine how well federal school bus standards were working to protect passengers from injury and whether changes in the standards were needed. This paper reports on the crash performance of small poststandard (manufactured after April 1, 1977) school buses and vans used for school transportation. Occupants of the small school buses generally fared well in the accidents investigated. As a result of this safety study, recommendations were issued to the National Highway Traffic Safety Administration, manufacturers of small school buses, and various associations of school-transportation officials and contractors. The recommendations include: conduct research on the design of restraining barriers; determine the feasibility of requiring lap/shoulder belts or other restraints with uppertorso support for passengers; collect data on roof and joint strength; amend federal performance standards for school bus windshield retention; develop performance standards for boarding door controls in certain small buses; and correct improper installation and use of lapbelts and other restraints. Appendices contain case summaries and indexes of cases, bus-design information, data on injuries and accidents, and a list of FMVS standards mentioned in the recommendations. (LMI) ENTIREDOCUMENT: POOR PRINTQUAD Reproductions supplied by EDRS are the best that can be made from the original document. Crashworthiness of Small Poststandard School Buses: Safety Study U.S. National Transportation Safety Board Washington, DC October 11, 1989 NTSB Number SS-89/02 U.S. DEPARTMENT OF EDUCATION Office of Educational Research and Improvement EDUCATIONAL RESOURCES INFORMATION CENTER (ERIC) This document has been reproduced as received from the person or organization originating it. 0 Minor changes have been made to improve reproduction quality. BEST COPY AVAILABLE Points of view or opinions stated in this document do not necessarily represent official OERI position or policy. 4,,t14-441q,.;.14-.6-.4araratjairAlkir PB89-?17003 Crashworthiness of Small Poststandard School Buses: Safety Study (U.S.) National TransportatioSafety Board. Washington, DC tl Oct 89 - ttstmematrativememovsiessurcess.. j . 4.11 ,I A, <7.41/ ', kt, i12:,,Zr" , ZUVRISMILUSIMONSINNOMPIEMIMMO,' larm=iassowtampanwamar, KS. Wetted if Cam= W belied kbrestio Unto 2 I\ REPRoaucAo ev U.S. DEPARTMENT OF COMMERCE own...new,NATIONAL TECHNICAL " .04FORMATV+ SERvICE The National. Transportation SafetyBoard is an independentFederal agency dedicated to promoting aviation, railroad,highway, marine, pipeline,and hazardous- materials safety: Established in1967, the agency is mandatedby the Independent Safety Board Act of 1974to investigate transportationaccidents, determine the probable cause of accidents,issue safety recommendations,study transportation safety issues, and evaluate the safetyeffectiveness of government agencies involved in transportation. The Safety Board makes public its actions and decisions through accidentreports, safety studies, special investigationreports, safety recommendations, reviews. Copies of these documents and statistical may be purchased from the NationalTechnical information Service, 5285 Port Royal, Road,Springfield, Virginia 22161.Detaiis on available publications may be obtained bycontacting: Public Inquiries Section National Transportation Safety Board 800_Independence Avenue, S.W. Washington, D.C. 20594 (202)3826735 4 T CH Report No. 2.Government Accession No. 3.Recipient's Catalog NTSB/SS-39/02 PH9-917003 No. Title and Subtitle 5.Report Date Safety Study: Crashworthincssof Small 0c...ob,.:r 11, 'r9 Poststandard School Buses ...Performing Organization 7. AJthor(s) Code g.Performing Organization Report N. Performing Organization Nameand Address 10.Work Unit No-. 5139A atioral iraosi,orl,:ation Safi::.y 20ard i;ureaJ of Safc:', Program II.Contract or Grant No. ...:ashi.igoo, D.C. 20594 I3.Type of Peport and . Period Covered I2.Sponsoring Agency Name and Address / -. Safnty S;uJy !9- NATIONAL TRANSPORTATION SAFETYBOARD Washington, D. C. -20594 ....... I47Ponsoring AgencyCode 15.Supplementary Notes J lo.Abstract This study reports on the crash performance of small poststandard (manufacturedafter April 1, 1977) school busesand vansused for school transportation. Occupants of these small school buses generally fared tefl in the accidents investigated. As a result.of this safety study, recommendations were issued to the National-Highway Traffic Safety Administration, manufacturers of small school buses.- and various associations ofschool officials and contractors. transportation The- recommendations fccuson the following safety issues: design of restraining barriers; feasibilitynf providing lao/stJulder belts or other restraints with upper tcrso support forpassengers; deficiencies in roof and joint strength; lack of Federal performance standards fs!' sChool bus . windshield retention; design of the boardingdoor controlsin cer'.1in small school buses; and the need to correct improper installation anduse of lapbelts and other restraints. I7.Key Words . , :.Distribution Statement School 1.Juses; sLhoni vAl;; restrai..:,ing barr12rs4 -,.':is strength; Ff-,:eralstaniArs:1; 101eltS; avallabll ,:*.rourIti toe rt:srairzs nne ":"chli..:al :nforma:Aor Service Snrin9f162, V4 Z?lfl -19.Security Classification 20.5ecurity Classification 21.No. 0 Pages 22.Price (of this repurt) fof this page/ UNCLASSIFIED UNCLASSIFIED 228 NTSR-Form 17t'A.2 (I.ev. W74) 5 BEST COPYAVAILABLE CONTENTS EXECUTIVE SUMMARY INTROOUCTION Definition of Small VersusLarge School Bus I Why This Study Was Conducted 2 Previous Studies of LargeSaool Buses 6 Studies of PassengerCirCrasi...s. 7 Accident Selection Criteria 7 How the InvestigationsWere Conducted IC 12 DIFFERENCES IN FEDERAL MOTORVEHICLE SAFETY STANDARDS FOR SMALL AND LARGE SCHOOLBUSES lapbelts 14 Vehicle Structure 14 Seating 14 14 OVERVIEW OF RESTRAINT USE-ANO INJURY ANALYSIS 18 RESTRAINT USE Deficiencies in Official 20 Reports of RestraintUse Restraints Incorrectly Codedas Lapbelts 21 .. _Improper Use of Lapbelts ____ _ .21 Unusual Configuration andInstal:ation of Restraints 22 22 INJURY OUTCOME Overall Passenger Outcome 28 Minor Injuries 28 Moderate and Above Injuries 28 Importance of Seating Position 28 Differences Between SafetyBoard and -Police 30 Accident Report Dataon Injury Severity Uniform School Bus AccidentReporting Form 30 31 RESTRAINING BARRIERS Crash Performance of Barriers 33 Consequences of Barrier Design .34 Risk of Head Injury 34 Canadian Crash Testson Risk of Head Injury 38 Anchorage Strength forRestraining Barriers 39 Criteria for Head Protection 40 . Lack of Criteria for Thoraxor Abdominal Injury 40 Possible Solutions to the 43 Problem of RestrainingBarrier Design Removal of RestrainingBarrier 44 Redesign of Barrier 44 Instaltation of Lap/ShoulderBelts 44 Rear-Facing Seats 46 Summary 48 49 STRUCTURAL INTEGRITY 51 Windshields 51 Inadvertent Door Opening 52 Joint Separations 55 EVACUATION 61 Fire and Fuel Tank Leaks 63' Emergency Exits 63 Special-Students 64 Lapbelt Release 54 CONCLUSIONS 66 RECOMMENDATIONS ,69 REFERENCES 72 APPENDIXES 75 A Index to Safety Board Study Case..: Involving School Vehicles Built to Fed6ral School Bus Standards 75 B Case Summaries of School Buses Built to Federal School Bus Standards 73 C Summary of Safety Issues by Case Number 160 0 Index to and Case Summaries of Small School Vehicles Not Built to Federal School Bus Standards 164 E Examples of Conflicting Classifications of School Buses 181 F Data on Public School Transportation, 1986-87 185 G School Bus Sales by Body Type, 1974-88 186 H School Bus Type Designations 187 I Abbreviated Injury Scale (AIS) 189 J Comparison of KABCO and AIS injury Scales 191 K Limitations of the KABCO Injury Codes 194 L Oata on Fatal School Bus Accidents .196 M Federal Motor Vehicle Safety Standards (MSS) Mentioned in Safety Recommendations 197 EXECUTIVE SUMMARY In 1977,a series of Federal Motor Vehicle Safety Standards(FMVSS) for school buses became effective, mandating different performance standards for school buses compared to other buses.Data on the crash performance of school buses .builttothesestandards were lacking, so the NationalTransportation Safety Board conducted a series of indepth accident investigations from 1984 to 1988 to determine how well Federal school bus standards are working to protect passengers from injury and whether changes in the standards are needed. Federalstandardsfor the design and operation ofschool buses diffFn. according to the passenger capacity and gross vehicle weight rating of the bus. The Safety Board, therefore, studied the performance