Occupant restraint system located in the rear passenger compartment of a vehicle

The passenger restraint system has a side airbag module (7) next to the side of the back seat facing the side body and covered by an elastically deformable cover (11) which is an integral part of a side member (9) of the back seat. The cover can be made of foam with its own covering and can be detachably fixed on the side body or side trim (12).