Accident studies in the UK have identified a number of instances where the door latch has been activated following a side impact, allowing rhe door to open and the occupant to be ejected. The latch activation occurs in cars having a pull rod linkage connecting the latch and interior release handle, through disturbance of the linkage following an impact by the occupant's shoulder or upper arm on the door inner panel.

An investigation into the phenomenon was conducted by MIRA and tests carried out which successfully reproduced this effect in the laboratory. It is proposed that this would be useful in predicting the behaviour of a vehicle door system as a development or legislative tool.

The test comprises an impact on the door's inside surface at 24.1 km/h (15 mile/h) by a resilient bodyform of 36 kg (80 lb) mass, reproducing the shape of the upper torso and shoulder.

In addition, a number of design changes to the door structure and linkage arrangement have been proposed to alleviate the problem.