Emb-135 first officer experiences an oxygen lo press annunciation at FL280. An emergency is declared...

Narrative:

Preflight indicated normal oxygen operation; and a pressure of about 1;900 psi. At cruise at FL280; we got an oxygen lo press annunciation. We declared an emergency; and as per checklist we descended to 10;000 feet. We decided it was safest to divert to ZZZ; as it was the closest airport from our descent. Dispatch was informed; and concurred with our choice of declaring an emergency and diverting to ZZZ. Dispatch informed us we were over maximum landing weight and needed to burn off fuel before landing. We were vectored by approach at 10 thousand feet in the northern vicinity of the airport until we did not exceed maximum landing weight. The weather was VFR; the approach and landing were normal and without incident. During the post flight inspection we found the 'oxygen disc' had burst in flight; causing the loss of oxygen.

Original NASA ASRS Text

Title: EMB-135 First Officer experiences an OXYGEN LO PRESS annunciation at FL280. An emergency is declared and descent initiated with diversion to a suitable alternate. Post flight reveals that the oxygen blow out disc had burst in flight.

Narrative: Preflight indicated normal oxygen operation; and a pressure of about 1;900 PSI. At cruise at FL280; we got an OXYGEN LO PRESS annunciation. We declared an emergency; and as per checklist we descended to 10;000 feet. We decided it was safest to divert to ZZZ; as it was the closest airport from our descent. Dispatch was informed; and concurred with our choice of declaring an emergency and diverting to ZZZ. Dispatch informed us we were over maximum landing weight and needed to burn off fuel before landing. We were vectored by Approach at 10 thousand feet in the northern vicinity of the airport until we did not exceed maximum landing weight. The weather was VFR; the approach and landing were normal and without incident. During the post flight inspection we found the 'oxygen disc' had burst in flight; causing the loss of oxygen.

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.

Attributes
ACN	1136144
Time
Date	201312
Local Time Of Day	0001-0600
Place
Locale Reference	ZZZ.ARTCC
State Reference	US
Aircraft 1
Make Model Name	EMB ERJ 135 ER/LR
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Flight Plan	IFR
Component
Aircraft Component	Oxygen System/Crew
Person 1
Function	First Officer Pilot Not Flying
Events
Anomaly	Aircraft Equipment Problem Critical

Emb-135 first officer experiences an oxygen lo press annunciation at FL280. An emergency is declared and descent initiated with diversion to a suitable alternate. Post flight reveals that the oxygen blow out disc had burst in flight.