B737-700
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 91
Human-Machine Interface
Aircraft Equipment Problem Critical
General Maintenance Action
Aircraft; Company Policy; Procedure
At about two hours into our three-hour flight; the First Officer needed to leave the cockpit to use the lavatory. I took my oxygen mask out the holder; cleaned it; and noticed that there seemed to be a small leak in one of the inflatable straps. A logbook entry was made to replace the mask. My concern is how often these masks are checked out of the aircraft container by Maintenance. I believe these masks should be fully checked (out of the container) each day.
When the First Officer left the cockpit for a break a B-737NG Captain donned his O2 mask and discovered a leak in the self inflating harness. The Captain expressed concern as to the frequency of operational inspection of the masks.