The design criteria for structures or ‘hardware’ installed on the sides of roadways requires suitable vehicle, occupant, and structural behaviour. The response of the roadside hardware and vehicle are measured or directly observed during proof-of-compliance crash tests. However, the occupant safety is currently inferred from the recorded vehicle dynamics and assessed using a simplified, lumped mass model of the occupant. Thresholds for these predicted occupant kinematics determine the suitability of the roadside equipment. The present risk assessment procedure is compared to a multi-body mathematical representation of the occupant motion for similar crash conditions. The purpose of the study is to identify the effectiveness and potential shortcomings of the current approach.