A B737-300 at top of climb at FL350 diverted due to loss of crew emergency oxygen pressure.

Attributes
ACN	528259
Time
Date	200110
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	msl single value : 35000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zzz.artcc
Operator	common carrier : air carrier
Make Model Name	B737-300
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : cfi pilot : atp
Experience	flight time last 90 days : 150 flight time total : 10900 flight time type : 2000
ASRS Report	528259
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	aircraft equipment problem : critical maintenance problem : improper documentation maintenance problem : improper maintenance non adherence : published procedure non adherence : far
Independent Detector	other flight crewa other flight crewb
Resolutory Action	flight crew : diverted to another airport
Consequence	other
Supplementary
Problem Areas	Maintenance Human Performance Aircraft
Primary Problem	Maintenance Human Performance

Narrative:

After having the crew oxygen bottle changed in ZZZ, the oxygen psi was about 1800 psi. After departing ZZZ for ZZZ1 and after leveling off at FL350, we noticed that the crew oxygen was now indicating zero. We decided to make a cautionary landing in ZZZ3 for repairs. We were told by maintenance that there must be a leak somewhere in the system.

Original NASA ASRS Text

Title: A B737-300 AT TOP OF CLB AT FL350 DIVERTED DUE TO LOSS OF CREW EMER OXYGEN PRESSURE.

Narrative: AFTER HAVING THE CREW OXYGEN BOTTLE CHANGED IN ZZZ, THE OXYGEN PSI WAS ABOUT 1800 PSI. AFTER DEPARTING ZZZ FOR ZZZ1 AND AFTER LEVELING OFF AT FL350, WE NOTICED THAT THE CREW OXYGEN WAS NOW INDICATING ZERO. WE DECIDED TO MAKE A CAUTIONARY LNDG IN ZZZ3 FOR REPAIRS. WE WERE TOLD BY MAINT THAT THERE MUST BE A LEAK SOMEWHERE IN THE SYS.

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.