Oxygen is a gaseous element common in the atmosphere of class M planets, although at relatively low levels (about 20% on Earth, for example).
Oxygen was vital for the survival of most carbon-based lifeforms. Some lifeforms, however, had adapted to go without oxygen for extended periods of time, such as Fantome from the Void, who had a very large lung capacity. (VOY: "The Void")
In 2259 of the alternate reality, Khan Noonien Singh reminded Spock that his crew did not require oxygen to survive as USS Enterprise's did, being kept in stasis, and it would involve merely cutting off their life support systems to kill them all. (Star Trek Into Darkness)
One of the tests given at Starfleet Academy involved working in an atmosphere that was oxygen deficient. Choriocytosis produced similar symptoms to the conditions of the test. (TAS: "The Pirates of Orion")
During a scan of Aldean DNA, Doctor Beverly Crusher was able to confirm that a drop in atmospheric O2 was not responsible for the Aldeans' sterility. (TNG: "When The Bough Breaks")
One species, the Benzites, could not breathe the oxygen-nitrogen atmosphere deemed "normal" by most Federation species. (TNG: "Coming of Age")
When Kira Nerys and Doctor Julian Bashir beamed aboard the Kobliad transport Reyab, Bashir noted that the vessel's O2 pressure levels were dropping. (DS9: "The Passenger")
In 2369, the runabout USS Ganges returned from a routine mission in the Gamma Quadrant to Deep Space 9 due to a power failure, their life support and oxygen levels dropped dangerously low. (DS9: "Q-Less")
After the alien probe "Pup" damaged most of the station's systems in 2369, a plasma fire occurred in a corridor in the habitat ring. Major Kira Nerys gave Lieutenant Jones the order to bring portable oxygen and something to treat plasma burns. (DS9: "The Forsaken")
Oxygen was also a critical component of life support functions aboard most space-going craft. In 2374, while playing a hypothetical game with the delusion Trajis Lo-Tarik, Seven of Nine asked him to imagine that the oxygen on the bridge of the USS Voyager had been depleted and then sealed it with a level 3 force field. Later, Seven cut power to all life support in order to maintain power to the ship's stasis units, and a delusion of Captain Kathryn Janeway commented that without heat and oxygen it was "Goodbye, Seven." (VOY: "One")
Materials containing oxygen[]
- carbon dioxide
- carbon monoxide
- clancium oxide
- deuterium oxide
- dilithium hydroxyl
- DNA
- ferric oxide
- hydroxyl
- iridium oxide
- methyl oxide
- nitrogen tetroxide
- nitrogen oxide
- nitrous oxide
- veridium oxide
- water