Relating the Strength Capabilities of Children to the Design of School Bus Emergency Roof Hatches

Abstract

School bus emergency exits are regulated by the Federal Motor Vehicle Safety Standard (FMVSS) No. 217 which does not consider the strength capabilities of children. The purpose of this study was to evaluate the strength capabilities of children to determine the optimal force specifications required to operate school bus emergency escape roof hatches. Force exertions were measured using test apparatuses built to replicate the operating mechanisms of the emergency escape roof hatch on a school bus. Force and torque exertions of 33 subjects in the first grade were measured using an emergency escape roof hatch knob. Forty two percent of the measured maximum push force exertions on the emergency escape hatch knob were less than the 89 newton minimum force requirement specified by FMVSS No. 217. Matching the operational requirements of emergency exits to the strength capabilities of children can help improve the overall effectiveness of the emergency evacuation system.

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