Airbags are safety restraint devices, they utilize an accelerometer or impact sensors on a vehicle to deploy during an impact situation. Upon inflation, they restrain the vehicle occupant and reduce movement and injury during an accident. Airbags are made of a fabric bag designed to rapidly inflate typically with a pyrotechnic device during a collision. Some airbags may instead utilize a cylinder of compressed air instead of a pyrotechnic. Vehicles may have multiple airbags both in front of the occupants as well as on the sides of them to reduce injury for a side collision. Airbags are not intended to be a primary restraint like seat-belts but instead are a secondary restraint or supplemental restraint device.
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