Forensic Airbag Examination

In many traffic accidents each year, the probative question is which occupant of a vehicle was driving at the time of the crash.    

There are several methods for determining this issue, one of which is an examination of the injuries and clothing of the vehicle’s occupants for airbag deployment evidence.   

Most airbags use a solid-propellant type of material that produces a hot gas to inflate the airbags. The gasses in the airbags leave the inflator at a temperature as hot as 600°C. The hot gas escapes through the vent holes after deployment and also may leak through the stitching seams in the front of the airbag and singe the skin or clothing of the occupants.  Since driver and passenger airbags are constructed differently, the singe patterns on the occupants can be compared to the stitch pattern of the airbag to determine which occupant was driving the vehicle at the time of a crash.

Chemicals utilized as lubricants in some airbags can also transfer to the occupant.  Other trace evidence such as hairs, fibers and make-up can also transfer from the driver or passenger to the surface of the deployed airbags.

DNA testing of the airbag can also prove useful although, due to the nature of traffic crashes and the possibility of contamination by the injured and medical personnel, the analysis of singe patterns provide the best evidence of driver identity.

We utilize state of the art techniques such as scanning electron microscopy and photo-stereomicroscopy to document airbag singe patterns and employ a forensic DNA specialist to advise clients on DNA examination issues.