A B737-800 first officer oxygen mask harness failed in flight after the mask was removed from storag...

Attributes
ACN	966741
Time
Date	201108
Local Time Of Day	0601-1200
Place
Locale Reference	ZZZ.ARTCC
State Reference	US
Environment
Light	Daylight
Aircraft 1
Make Model Name	B737-800
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Route In Use	Oceanic
Flight Plan	IFR
Component
Aircraft Component	Oxygen System/Crew
Person 1
Function	Pilot Not Flying Captain
Qualification	Flight Crew Air Transport Pilot (ATP)
Person 2
Function	First Officer Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Aircraft Equipment Problem Critical

Narrative:

This incident occurred in cruise flight at FL370; just beyond the half way point to our destination. The first officer had removed his oxygen mask from its storage compartment and inflated the harness in preparation for donning the mask; when the harness burst internally. The mask would not inflate and was no longer usable. Exercising captain's emergency authority; I instructed the first officer to remove his O2 mask from its storage compartment and we would replace it with the O2 mask from the first observer's seat; as that seat was unoccupied. After donning my oxygen mask; he left his seat to retrieve the observer's mask and then installed it at the first officer mask location. He tested the new mask for proper operation including the microphone and we continued the flight to destination.

Original NASA ASRS Text

Title: A B737-800 First Officer oxygen mask harness failed in flight after the mask was removed from storage. The mask was swapped with the observer's seat mask.

Narrative: This incident occurred in cruise flight at FL370; just beyond the half way point to our destination. The First Officer had removed his oxygen mask from its storage compartment and inflated the harness in preparation for donning the mask; when the harness burst internally. The mask would not inflate and was no longer usable. Exercising Captain's Emergency Authority; I instructed the First Officer to remove his O2 mask from its storage compartment and we would replace it with the O2 mask from the First Observer's seat; as that seat was unoccupied. After donning my oxygen mask; he left his seat to retrieve the Observer's mask and then installed it at the First Officer mask location. He tested the new mask for proper operation including the microphone and we continued the flight to destination.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

A B737-800 first officer oxygen mask harness failed in flight after the mask was removed from storage. The mask was swapped with the observer's seat mask.