Collision Research Ltd.

Restraint Systems
The restraint system should not only be looked at as the seat belt and air bag systems, but also the design of the seat bottom, seat back, and knee bolsters, along with the geometry of the roof, dashboard, steering wheel, floor pan, and overall occupant compartment.

We are routinely asked to provide the answers to three basic questions in restraint system cases:

  • Was the occupant wearing the restraint system?
  • If the occupant was unbelted, would the injuries sustained have been prevented or mitigated by usage of the restraint system?
  • Did the restraint system operate properly?


In providing answers to these questions, we evaluate crash Delta-V, Principle direction of force, crash pulse, and occupant motion. We answer these questions by performing forensic vehicle and restraint system inspections whereby we document things such as vehicular crush, restraint system webbing stretch, witness marks on seat belt hardware , occupant compartment interior contact points, occupant compartment intrusion, and fit checks in either the accident vehicle, or an exemplar with similar sized human surrogates. Forensic analysis of these types of cases also takes into account analysis of injuries sustained by all occupants, site geometry, occupant anthropometry, and deposition testimony when available.