Action
Notice of proposed rulemaking (NPRM).
Summary
This document proposes upgraded flammability standards for thermal/acoustic insulation materials typically installed behind interior panels in transport category airplanes, by adopting new flammability test methods and criteria that specifically address flame propagation and entry of an external fire into the airplane (burnthrough) under realistic fire scenarios. This proposed rule change is considered necessary because the current standards do not realistically address situations in which thermal/acoustic insulation materials may contribute to the propagation of a fire. The proposed standards are intended to reduce the incidence and severity of cabin fires, particularly those ignited in inaccessible areas where thermal/ acoustic insulation materials are typically installed. In addition, these proposed standards are also intended to provide an increased level of safety with respect to post-crash fires by delaying the entry of such a fire into the cabin, thereby providing additional time for evacuation and enhancing survivability. These new standards, in addition to being proposed for new type designs, are also proposed for newly manufactured airplanes entering part 121 service. Additionally, the proposed flame propagation standards are also proposed for newly manufactured airplanes entering parts 91, 125, and 135 service.