2-33seat-mounted side impact androof-rail airbags, deployment isdetermined by the location andseverity of the side impact. In arollover event, roof-rail airbagdeployment is determined by thedirection of the roll.What Makes an AirbagInflate?In a deployment event, the sensingsystem sends an electrical signaltriggering a release of gas from theinflator. Gas from the inflator fills theairbag causing the bag to break outof the cover and deploy. The inflator,the airbag, and related hardware areall part of the airbag module.Frontal airbag modules are locatedinside the steering wheel andinstrument panel. For vehicles withseat-mounted side impact airbags,there are airbag modules in the sideof the front seatbacks closest to thedoor. For vehicles with roof-railairbags, there are airbag modules inthe ceiling of the vehicle, near theside windows that have occupantseating positions.How Does an AirbagRestrain?In moderate to severe frontal or nearfrontal collisions, even beltedoccupants can contact the steeringwheel or the instrument panel. Inmoderate to severe side collisions,even belted occupants can contactthe inside of the vehicle.Airbags supplement the protectionprovided by safety belts. Frontalairbags distribute the force of theimpact more evenly over theoccupant's upper body, stopping theoccupant more gradually.Seat-mounted side impact androof-rail airbags distribute the forceof the impact more evenly over theoccupant's upper body.Rollover capable roof-rail airbags aredesigned to help contain the headand chest of occupants in theoutboard seating positions in the firstand second rows. The rollovercapable roof-rail airbags aredesigned to help reduce the risk offull or partial ejection in rolloverevents, although no system canprevent all such ejections.But airbags would not help in manytypes of collisions, primarily becausethe occupant's motion is not towardthose airbags. See When Should anAirbag Inflate? on page 2-31 formore information.Airbags should never be regarded asanything more than a supplement tosafety belts.srx.book Page 33 Monday, June 8, 2009 8:28 AM
