Narrative:

While working a through trip, 1 hour on the ground, inbound pilots and passenger had left the aircraft but the inbound flight attendants were still on the aircraft and were going to work the outbound trip. While in the cockpit a flight attendant was using the 1ST observer oxygen and the crew oxygen was down to 1480 psi. She said that she had been feeling ill on the flight coming in and the pilots had been letting her use the crew oxygen. I left for 10 or 15 mins and when I returned the oxygen had dropped to 1430 psi. I told her to stop using it which she did. 2 other flight attendants seemed angry and surprised that I would tell her to stop. They argued that all B757's had poor air. They insisted that often while working the B757's, they felt bad in the cabin and would go to the cockpit to use oxygen and that the inbound pilots had given them permission to use it, and that if they used the portable oxygen bottles, they would then have to make log items to replace the bottles. While she was using the oxygen on the ground it dropped from 1480 psi to 1430 psi. If I had seen that drop and was unaware of her having used the oxygen, we would have had to take the aircraft OTS to look for an oxygen leak. Also it was almost down below our minimum dispatch pressure. There would have probably been a delay if I had had to service the oxygen since the service port is in the forward cargo pit and the ramp was in the middle of loading. At any rate if what they were telling me is true, that the flight crew's frequently use the emergency oxygen when there really isn't an emergency, there is a problem that should be looked into.

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Original NASA ASRS Text

Title: A B757-200 WHILE PARKED ON GATE A TECHNICIAN NOTES DEPLETION OF CREW OXYGEN AND DISCOVERS CABIN ATTENDANT USING CREW OXYGEN.

Narrative: WHILE WORKING A THROUGH TRIP, 1 HR ON THE GND, INBOUND PLTS AND PAX HAD LEFT THE ACFT BUT THE INBOUND FLT ATTENDANTS WERE STILL ON THE ACFT AND WERE GOING TO WORK THE OUTBOUND TRIP. WHILE IN THE COCKPIT A FLT ATTENDANT WAS USING THE 1ST OBSERVER OXYGEN AND THE CREW OXYGEN WAS DOWN TO 1480 PSI. SHE SAID THAT SHE HAD BEEN FEELING ILL ON THE FLT COMING IN AND THE PLTS HAD BEEN LETTING HER USE THE CREW OXYGEN. I LEFT FOR 10 OR 15 MINS AND WHEN I RETURNED THE OXYGEN HAD DROPPED TO 1430 PSI. I TOLD HER TO STOP USING IT WHICH SHE DID. 2 OTHER FLT ATTENDANTS SEEMED ANGRY AND SURPRISED THAT I WOULD TELL HER TO STOP. THEY ARGUED THAT ALL B757'S HAD POOR AIR. THEY INSISTED THAT OFTEN WHILE WORKING THE B757'S, THEY FELT BAD IN THE CABIN AND WOULD GO TO THE COCKPIT TO USE OXYGEN AND THAT THE INBOUND PLTS HAD GIVEN THEM PERMISSION TO USE IT, AND THAT IF THEY USED THE PORTABLE OXYGEN BOTTLES, THEY WOULD THEN HAVE TO MAKE LOG ITEMS TO REPLACE THE BOTTLES. WHILE SHE WAS USING THE OXYGEN ON THE GND IT DROPPED FROM 1480 PSI TO 1430 PSI. IF I HAD SEEN THAT DROP AND WAS UNAWARE OF HER HAVING USED THE OXYGEN, WE WOULD HAVE HAD TO TAKE THE ACFT OTS TO LOOK FOR AN OXYGEN LEAK. ALSO IT WAS ALMOST DOWN BELOW OUR MINIMUM DISPATCH PRESSURE. THERE WOULD HAVE PROBABLY BEEN A DELAY IF I HAD HAD TO SVC THE OXYGEN SINCE THE SVC PORT IS IN THE FORWARD CARGO PIT AND THE RAMP WAS IN THE MIDDLE OF LOADING. AT ANY RATE IF WHAT THEY WERE TELLING ME IS TRUE, THAT THE FLC'S FREQUENTLY USE THE EMER OXYGEN WHEN THERE REALLY ISN'T AN EMER, THERE IS A PROB THAT SHOULD BE LOOKED INTO.

Data retrieved from NASA's ASRS site as of July 2007 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.