Side airbags are of low-volume type and are positioned in the outer seat-back bolster of each front seat to protect the occupant's chest. The chest is the area most prone to injury in a side-on collision.
OPDS determines the size and position of the passenger, and prevents deployment whenever it could cause head or neck injuries. It also alerts the driver by a warning light when the passenger's position is unsuitable for side airbag deployment. The passenger's seat-back incorporates six position sensors running from top to bottom. These determine the height and position of the occupant. A further sensor is incorporated into the left-hand seat-back bolster, this determines the lateral position of the occupant. Monitored on a continuous basis, signals from these sensors allow OPDS to determine the passenger's seated position. In a side-on collision OPDS can then calculate if it is safe to deploy the side airbag or not.