According to the Traffic Safety Facts reports from 1999- 2003, an average of 40 fatalities and 18,430 injuries of bus occupants occurred per year. The objectives of this research are to characterize the kinematics and injury mechanisms of bus passengers during typical frontal, side and rear impact conditions. Accident data from the traffic Safety Fact Reports, Buses Involved in Fatal Accidents Report and Transit Agency data were review to define typical crash scenarios. A detailed finite element model of a low floor transit bus was used to calculate the crash pulses at the passenger compartment for typical frontal, side and rear impact conditions. A series of sled tests with 5th, 50th and 95th percentile occupants were conducted at NIAR’s Crash Dynamics Laboratory in order to study the occupant kinematics and to identify injury mechanisms to bus passengers.

The results of this study show that the most common injury mechanisms to bus passengers are head (HIC) and neck injuries (neck extension, flexion and compression). These injuries are due to body-body contact between unrestrained passengers and/or body-to-seat structure contacts.