AD FAA-2013-0453

These special conditions are issued for the Boeing Model 717- 200 series airplanes. These airplanes will have a novel or unusual design feature associated with seats with inflatable lapbelts. The applicable airworthiness regulations do not contain adequate or appropriate safety standards for this design feature. These special conditions contain the additional safety standards that the Administrator considers necessary to establish a level of safety equivalent to that established by the existing airworthiness standards.