In an impact of sufficient severity, the airbag sensing system detects that the vehicle is in a crash. For both the frontal and side impact airbags, the sensing system triggers a release of gas from the inflator, which inflates the airbag. The inflator, airbag and related hardware are all part of the airbag modules inside the steering wheel, instrument panel and the side of the front seatbacks and behind the rear seatbacks closest to the door.