An increasing number of new vehicles also are equipped with safety devices referred to as side airbags or SIPS, side impact protection systems. These airbags may be located in the outboard edge of the seat back, in the door, the pillars in front of and behind the front doors or in the roof rail above the door. Seat and door-mounted systems all provide thoracic protection.
Some models have airbags which extend upwards to also provide head protection.
Two types, known as inflatable tubular structures and inflatable curtains, are designed to reduce the chance of head injury and to help keep the head and body inside the vehicle. Most side airbag systems are designed for front seating positions, but some vehicles also utilize side airbag technologies in rear seating positions. A few vehicles also utilize inflatable curtains to help keep the head and body inside the vehicle in rollover crashes. While side airbags are smaller and use less propellant than front airbags, they deploy very rapidly. Occupants should never rest against a side airbag module.