Narrative:

I was called at home and told that company maintenance had disclosed that our flight had its oxygen shut off internally by maintenance. So I can tell you that on my usual pre-flight; I turned on the [crew oxygen] O2 with the cockpit switch. Pressed the 'push to test switch' on my mask and jump-seat mask next to mine; and both tested O.K. Having not needed to go the lavatory in flight; I could not tell that the O2 system wasn't working correctly. I have caught bad mask before; not working properly and had them replaced. Having been recently sick with the flu; I am reluctant to put a mask on to test it during these epidemic times.

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Original NASA ASRS Text

Title: Four pilots were informed the Crew Oxygen (O2) supply bottle handle on their A319 aircraft was found in the closed position by Maintenance. Flight crews did not notice any oxygen supply discrepancies after two days of flying.

Narrative: I was called at home and told that company Maintenance had disclosed that our flight had its oxygen shut off internally by Maintenance. So I can tell you that on my usual pre-flight; I turned on the [Crew oxygen] O2 with the cockpit switch. Pressed the 'Push to Test switch' on my mask and Jump-seat mask next to mine; and both tested O.K. Having not needed to go the Lavatory in flight; I could not tell that the O2 system wasn't working correctly. I have caught bad mask before; not working properly and had them replaced. Having been recently sick with the Flu; I am reluctant to put a mask on to test it during these epidemic times.

Data retrieved from NASA's ASRS site as of July 2013 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.