|For the similar item in Fallout 76, see Decontamination shower.|
The decontamination arch is a settlement object that, when powered and switched on, removes all radiation from the player character when they pass through it. It can be constructed at any friendly settlement, and requires two units of power to function. Its built-in switch can be used to activate and deactivate it, so it does not require an external switch.
Fiber optics (6)
Decontamination arch (1)
Even though the arch is supposed to remove all radiation, it actually removes all but 1 point of radiation, so when your health points are viewed in the stats window it shows health at (Max HP - 1)/(Max HP).[verified]