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BC Transit, a crown corporation in the province of British Columbia, has reported injuries resulting from passengers sliding off seats during extreme braking and/or turning maneuvers. The corporation was eager to determine whether seat design could help minimize the likelihood of passengers sliding off seats and initiated a review of existing forward facing seats. The review examined seats of different designs within the corporate fleet plus a prototype seat. Without the advantage of seat compartmentalization, passive restraints or seat belts to reduce occupant movement during harsh maneuvers or in a collision, seat design in the first forward facing position should consider characteristics that provide passive restraint for the occupant. Tests using a weighted body form and three common clothing fabrics set against each seat cushion found a surprisingly wide range of friction values.

Accident investigations and empirical information are used to evaluate the performance of the occupant's seatback for frontal and rear impact collisions. The role of the seatback is to prevent rear seat objects from intruding into the occupant's space (frontal impacts) and to keep the occupant from moving rearward out of this zone (rear impacts). Trends in the dynamic performance of the seatback are identified and are discussed relative to the current government safety standards. The results indicate that bucket seats could be improved to better protect the occupant during collisions. The strength requirements in present standards appears to be inadequate to protect the occupant from seatback collapse during a modest collision. These standards only consider the effects of the seat's mass and do not account for inertial loading of the occupant or any other externally applied impulsive loads.