Airworthiness Directives; Zodiac Aerotechnics (Formerly Intertechnique Aircraft Systems) Oxygen Mask Regulators

We are adopting a new airworthiness directive (AD) for certain Zodiac Aerotechnics (formerly Intertechnique Aircraft Systems) oxygen mask regulators. This AD was prompted by a report of a malfunctioning mask having an inflatable harness with a high premature rupture rate due to defective silicon. This AD requires inspecting and replacing defective harnesses with new or modified serviceable units. We are issuing this AD to detect and correct defective harnesses, which could lead, in case of a sudden depressurization event, to a harness rupture, thereby providing inadequate protection against hypoxia and possibly resulting in unconsciousness of the affected flightcrew member and consequent reduced control of the airplane.