What Makes an Airbag Inflate?In a deployment event, the sensing system sendsan electrical signal triggering a release of gas fromthe inflator. Gas from the inflator fills the airbagcausing the bag to break out of the cover and deploy.The inflator, the airbag, and related hardware areall part of the airbag module.Frontal airbag modules are located inside thesteering wheel and instrument panel. For vehicleswith roof-rail airbags, there are airbag modules inthe ceiling of the vehicle, near the side windowsthat have occupant seating positions.How Does an Airbag Restrain?In moderate to severe frontal or near frontal collisions,even belted occupants can contact the steeringwheel or the instrument panel. In moderate to severeside collisions, even belted occupants can contactthe inside of the vehicle.Airbags supplement the protection provided bysafety belts. Frontal airbags distribute the force of theimpact more evenly over the occupant’s upper body,stopping the occupant more gradually. Roof-rail airbagsdistribute the force of the impact more evenly overthe occupant’s upper body.Rollover capable roof-rail airbags are designed tohelp contain the head and chest of occupants in theoutboard seating positions in the first and second rows.The rollover capable roof-rail airbags are designed tohelp reduce the risk of full or partial ejection in rolloverevents, although no system can prevent all suchejections.But airbags would not help in many types ofcollisions, primarily because the occupant’s motionis not toward those airbags. See When Should anAirbag Inflate? on page 1-61 for more information.Airbags should never be regarded as anythingmore than a supplement to safety belts.1-63
