Scattered throughout the world of Rapture, Vita Chambers will revive you if you are ever killed by the denizens of Rapture. Note that when revived, enemies will retain the amount of health you left them with before dying. Vita Chambers are usually found whenever you reach a new area of Rapture that is cut off or separate from the previous area covered by another Vita Chamber.
You can choose whether to disable them or not. If killed when the Vita Chambers are disabled you will not be revived but instead will need to load your last saved game to continue.
There are two trophies that are obtainable if you complete the game without the devices: "A Man Chooses" (complete the game on Hard difficulty without using a Vita Chamber) and "I Chose The Impossible" (complete the game on Survivor difficulty without using a Vita Chamber).
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