Summary
We propose to adopt a new airworthiness directive (AD) for certain Zodiac Aerotechnics oxygen mask regulators. This proposed AD was prompted by reports that certain silicon harness inflation hoses, installed on certain flight crew quick donning mask harnesses, have shown an unusually high premature rupture rate. This proposed AD would require inspection and replacement of oxygen mask regulator harness inflation hoses. We are proposing this AD to address the unsafe condition on these products.