Evaluation of Door Latch Response to Vertical Loading Conditions

Field research has consistently demonstrated that the risk of occupant death or serious injury in motor vehicle crashes is significantly reduced when occupants are retained within the vehicle.[1][2] The injury prevention benefits of passenger vehicle door systems require that they remain closed during collisions. Federal Motor Vehicle Safety Standards (FMVSS) and SAE Recommended Practices set forth door latch performance requirements to “minimize the likelihood of occupants being thrown from the vehicle as a result of impact”. Currently, there is not a vertical latch strength requirement for hinged side doors in FMVSS 206. A recent study has raised concerns about latch performance in response to vertical loading conditions. In order to investigate door latch performance in response to vertical loading conditions, the latch must be evaluated using techniques more representative of loading conditions in real world accidents.

This study investigates side door latch performance in full vehicle and door system component testing as opposed to the component-only fixture testing outlined in FMVSS 206. Both full vehicle and door system testing showed that the tested side door latches managed forces that were substantially higher than any loads required by FMVSS 206 when subjected to purely vertical loading.