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Officially, the vaults were nuclear shelters designed to protect the American population from nuclear holocaust. Apart from that, the level also contained the computer core (with the vault's AI monitoring the shelter 24/7), housing data processing units, a library playing an important role in educating vault dwellers, a common meeting room, and the primary store room, where the most important supplies would be stored. A security guard was posted in the command center at all times, to ensure that the armaments were properly secured and handed out only to people possessing the proper clearance from the overseer. The operations center, apart from the seat of power, included the computer lab, where the water purification system was located, and an armory, where the vault's weapons, ammunitions and armor were stockpiled. Heart of the vault, the command center was where the overseer's seat was located. A standard level had 20,000 square feet of usable area. Vault 13 had one hundred living quarters, and at maximum capacity, ten people would be assigned to a single living quarter, in a hot- bunking system. Standard pre-War design of the living quarters was that of a single room with a sanitary annex. The entrance also containes consoles and Emergency Medical Labs, and can only be opened via security codes. For most vaults this the only means of entering or leaving. It is closed from the inside by a reinforced high-security door and from the outside by a massive, gear-shaped, four-foot thick vault door. The entrance houses the Vault's only connection to the outside world - the airlock. The vaults of the West Coast differ from those constructed in the vicinity of Washington, DC and the Mojave area, for example. The vaults are all very similar in their basic functions, but sometimes were constructed according to different designs. But in reality, they were used as a secret experiment for the government.
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Officially, they were designed for the sole purpose of sheltering up to one thousand dwellers from a nuclear holocaust. A Vault is a type of subterranean installation designed by Vault-Tec.
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