Narrative:

On feb/mon/03, I was called to flight operations. The captain reported that oxygen pressure dropped 200 psi when testing the masks. I went down to the forward cargo bin, accessed the oxygen bottle and found the shutoff valve nearly closed. I would say between 1/8 and 1/4 turn open. I opened the valve fully, then closed 1/4 turn per maintenance manual. All system checked normal per maintenance manual. Maintenance performed.

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Original NASA ASRS Text

Title: A B737-700 CREW OXYGEN BOTTLE WAS RPTED AS DROPPING 200 LBS WHEN TESTED. RPTR FOUND SHUTOFF VALVE ON 02 BOTTLE IMPROPERLY ADJUSTED.

Narrative: ON FEB/MON/03, I WAS CALLED TO FLT OPS. THE CAPT RPTED THAT OXYGEN PRESSURE DROPPED 200 PSI WHEN TESTING THE MASKS. I WENT DOWN TO THE FORWARD CARGO BIN, ACCESSED THE OXYGEN BOTTLE AND FOUND THE SHUTOFF VALVE NEARLY CLOSED. I WOULD SAY BTWN 1/8 AND 1/4 TURN OPEN. I OPENED THE VALVE FULLY, THEN CLOSED 1/4 TURN PER MAINT MANUAL. ALL SYS CHKED NORMAL PER MAINT MANUAL. MAINT PERFORMED.

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.