34 and 40 further provides inflation gas to deploy air bag 46 air bag assembly 44 may also include a so called cold gas inflator 148 taking the place of inflator tube 48 inflator 148 would generate gas upon receiving high pressure gas from gas genenerator 36 but does not require a separate firing line thus for an embodiment of system 10 using cold gas inflator 148 gas pressure from gas source 36 initiates the release of inflation gas such a configuration provides the benefit that gas source 36 does not need to have the gas generation capacity or proximity to air bag 46 to provide rapid inflation of the air bag yet preserves the benefit of using a single firing line 52 to inflate the air bag and provide belt pretensioning in a preferred embodiment of the present invention each of the aforementioned components including seat belt webbing 12 retractors 24 and 28 and air bag assembly 44 are mounted to seat 22 thus when the seat is moved fore and aft to adjust to various occupants sizes each of these components moves with the occupant as mentioned previously a fundamental benefit of the system in accordance with this invention is the use of a common gas source 36 and its associated firing line 52 to provide both seat belt pretensioning functions and side impact air bag inflation various alternative configurations of the restraint assembly in accordance with this invention may be implemented while implementing the novel features of the present invention for example lap belt retractor 28 may be eliminated in favor of a fixed lap.