This report covers the final design and implementation plan for evaluating the effectiveness of FMVSS 220 (School Bus Rollover Protection), FMVSS 221 (School Bus Body Joint Strength), and FMVSS 222 (School Bus Seating and Crash Protection). The plan for the evaluation study considers measurability criteria, alternative statistical and laboratory techniques, data availability/collectability, resource requirements, work schedule, and other factors. The objective of all three standards is to reduce the frequency and severity of injury in school bus accidents. FMVSS 220 and 221 establish requirements for the structural integrity of the bus, while FMVSS 222 relates to the bus interior. The effective date of the three Standards is April 1, 1977. At present, there is little detailed data on school bus accidents, making it difficult to evaluate Pre-and Post-Standard effectiveness. New data will be required from detailed accident investigation teams such as MDAI and NASS. Also school buses are manufactured at a relatively low rate (about 30,000/year) and it will take several years to accumulate sufficient accident data on Post-Standard vehicles. The plan described herein takes two general approaches: (1) statistical analysis of available and future detailed accident data; and (2) acquistion of new test and field data. To carry out these approaches, methodologies for five evaluation programs are presented herein. Two effectiveness evaluation programs involve straight-forward processing of existing data and more detailed data which will be forthcoming. Two others call for acquiring laboratory and field data. The program for determining cost of the Standards requires obtaining data from the manufacturers. It is estimated that the entire program would take about three years to complete at a cost of about $1,268,000.
Abstract