Initiate Vault Decontamination

Initiate Vault Decontamination is a main quest in Fallout: Brotherhood of Steel. It is given to the Initiate on level 4 of the Vault-Tec Corporate Vault Laboratories.

Quick walkthrough
Get to the emergency decontamination center and activate the vault decontamination sequence to kill the giant blob.

Detailed walkthrough
Patty failed to activate the emergency decontamination procedure and asks the Initiate to do this. Activate the switch next to Patty and enter the emergency room. There is a blob mouth here which must be dealt with (Oh Shit! (Part 2)).

Flipping the switch on the machine behind the blob mouth activates the decontamination sequence and starts a 120-second countdown, before a nuclear device will destroy the entire vault. Take the monorail next to the save point to get to Level 1 of the laboratories. From there, proceed to the other end of the platform and reach another monorail. Once activated, the escape is complete and a cutscene will play.