1.   And Irvine understood how the oxygen system worked.

2.   As power drained out of them, light, temperature control and the oxygen generation system were all shut down to save energy.

3.   Airlines use them in their emergency oxygen systems, but the FAA banned passenger airlines from carrying them as freight after the Valujet crash.

4.   French stocks worth a look include Intertechnique, a maker of oxygen systems, and Labinal, which makes aeronautical equipment.

5.   Last week, its oxygen system broke down, forcing the crew to breathe using canisters of air.

6.   Lee could not say why the oxygen system for the two men in the HumVee malfunctioned.

7.   More efficient oxygen systems became available for those needing it, and airlines began modifying their policies to provide for the disabled.

8.   Navy investigators acknowledged that the oxygen system could have failed.

9.   Oxygen generation systems aboard the Mir space station were operable again Tuesday, easing U.S. concerns that yet another problem on the beleaguered outpost might force its evacuation.

10.   That may explain why nobody bothered to announce the failure of the main oxygen system until Tuesday.