From Halopedia, the Halo wiki
Building 41 is a red-level secured building in Chawla Base. Its only entrance is a set of heavy steel doors, similar to a bank vault. It contains a clean room lab, used in 2552 by Major Standish's men to study the Deep-Space Artifact. In order to prevent corrosion and electrical arcing, the lab was filled with argon, forcing the scientists to wear vacsuits. In October 2552 the members of Team Jersey infiltrated the building and its lab in order to deactivate the artifact. Upon completing their mission the Durga used a Scorpion tank to blow a hole in the building's walls, allowing all of the members of Team Jersey to escape, with the exception of Rani Sobeck, who was apprehended.
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