Airworthiness Directives; Puritan Bennett Aero Systems Company Series 174290 Constant Flow Airline Portable Oxygen Masks, Part Numbers 174290-14, 174290-24, 174290-34, 174290-44, and 174290-54

This amendment adopts a new airworthiness directive (AD) that applies to Puritan Bennett Aero Systems Company (Puritan Bennett) Series 174290 Constant Flow Airline Portable Oxygen Masks, Part Numbers 174290-14, 174290-24, 174290-34, 174290-44, and 174290-54, that are utilized on aircraft. This action requires replacing any Series 174290 Constant Flow Airline Portable Oxygen Masks, Part Numbers 174290-14, 174290-24, 174290-34, 174290-44, and 174290-54, that have a manufacturing date between September 1992 to August 1996 with an FAA- approved mask that incorporates a part number not covered by this AD. These masks have a connector with an orifice that could restrict more than half of the oxygen flow to the passenger. This oxygen mask is mainly used for emergency medical action or emergency decompression procedures during flight. The actions specified by this AD are intended to prevent restricted oxygen flow, which, if not corrected, could cause serious injury to a passenger in need of emergency or first aid oxygen during flight.