Every sector of the Mars station contains an Oxygen Generator to produce the atmosphere necessary for human habitation, and every Generator requires an intact Oxygen Filter and Power to function.

At the start of the game, only two of the station's Oxygen Generators remain functional - the ones in the Prison and Central Control sections. Producing and installing fresh Oxygen Filters, and restoring power to sectors, will both slow the spread of infection in an area and allow West to visit the area without requiring a personal oxygen supply.