Yellow pass key - The Glow, level 1, on D. Allen's corpse. For use of the first elevator.
Red pass key - The Glow, level 2, on a burnt corpse in the northeast corner. Used for the 2nd elevator.
Blue pass key - The Glow, level 4, on the burnt corpse of Charles Ringhold. For use on the 3rd elevator, access Level 5.
Red pass key - Found in Gecko's nuclear power plant, on a shelf in the room adjacent to both the yellow- and blue pass key rooms. Used to unlock part of the power plant.
Yellow pass key - In Gecko's nuclear power plant, room near the supply room. Also found in a locker in Percy's house in the Gecko junkyard. Also used to unlock part of the power plant.
Blue pass key - In Gecko's nuclear power plant, on a shelf in the room next to the yellow pass key. Can also be stolen from Dr. Schreber's desk in his lab at Navarro underground; it can either be taken while in sneak mode or after he is killed. Used to unlock the utility tunnel leading to the imprisoned Xarn.
Red and yellow pass key is carried by a ghoul near the supply room.