Gametitle-FO1.pngGametitle-FO2.pngGametitle-FO3.pngGametitle-FNV.pngGametitle-FOT.pngGametitle-FOBOS.pngGametitle-VB.pngGametitle-FB.pngPenny Arcade.gif

Vault-Tec advert and in-game town map of Vault 13

Inside Vault 101

A Vault is a type of subterranean installation designed by Vault-Tec. Officially, they were designed for the sole purpose of sheltering up to one thousand dwellers from a nuclear holocaust. But in reality, they were actually used as a secret experiment for the government.


Commissioned by the United States government as part of Project Safehouse, Vault-Tec built 122[1] such Vaults over the country. However, when the storm of nuclear war came in 2077, the Vaults were sealed without many of their dwellers due to the Cry Wolf effect training drills had on the populace.

The first Vault was built in Los Angeles, intended to demonstrate the viability of such a facility. The demonstration Vault was built beneath the city, within its limits and unlike other Vaults, wasn't part of the experiment. Most Vaults were completed by 2063, except for Vault 13, which was the last one to be completed.


The Vaults were one of the most expensive shelters in the pre-War world, as according to the Vault Dweller's Survival Guide for Vault 13 (otherwise known as the Fallout manual), the intended budget for that particular installation was 400 billion dollars, and by the end of its construction reached 645 billion (although it should be mentioned that this is likely a price inflated to modern day prices; there are advertisements for vehicles in Fallout 3 loading screen slides with prices saying "'Only' $1,000,000," leading to the assumption that the 645 billion dollar price tag would not be comparable to modern day prices). The Vaults were located in various locations, and little information is available as to why those particular sites were chosen, although the most logical conclusion is that they were simply located away from predicted nuclear strike priority targets. As such, very few of them have reinforced entry shafts.

Each Vault was designed to hold one thousand occupants at any given time, although hot bunking was required at maximum capacity, and equipped with all facilities and supplies needed by them to survive in isolation for the designated time. According to the Vault 101 PA System, the life support system could work for over 900 years without failure. The facilities and supplies included complete construction equipment, hydro-agricultural farms, a water purification system, defensive weaponry to equip 10 men, communication systems and surface monitors, social, and entertainment files (for total duration). Waste management was conducted by burning trash on scheduled "burning days". Larger incinerator receptacles were used for the destruction of human corpses. In addition, some Vaults received one or two G.E.C.K.s, intended to help the inhabitants repopulate the post-nuclear world after the All Clear signal is sent following the conclusion of the social experiment.

Different types of power sources were utilized for the Vaults. Vault 13 relied primarily on geothermal energy, with backup power available from a General Atomics Nuclear Power generator, and could sustain one thousand inhabitants for two hundred years. Vault 8 on the other hand, relied on an inefficent nuclear reactor[2], which, while enough for Vault City to emerge, could only support a relatively small, highly advanced settlement, and in 2241 was nearing its capacity, after which further growth would be impossible.

All vault dwellers wear blue-and-yellow jumpsuits, although the design varied between different Vaults. The typical vault dweller living in a properly maintained Vault could expect to live an average of 92.3 years[3].

Needless to say, most Vaults in the experiment failed and had results completely different than those advertised, such as the creation of Super Mutants. Even those who exited successful Vaults seem to suffer from xenophobia and agoraphobia, or fears of strangers and open places; notable examples would be Michael Angelo, who doesn't dare leave the Strip even for inspiration, the Boomers who shoot artillery at anything that comes close to them, and the Vault 101 citizens, who still don't exit the Vault even after the Lone Wanderer opens its door (if he chooses to do so.) Notable exceptions would be the Vault Dweller, the Lone Wanderer and Butch DeLoria.

It should be noted that due to scaling, the size of Vaults in games shouldn't be taken at face value - none of the Vaults which can be entered in the series have enough space or facilities to actually house 1000 people (or rather 500, as hot bunking system is in effect at maximum capacity). However, many doors within in-game vaults are inaccessible, which allows for the possibility that the vault is far larger than the areas the player can access.



The entrance houses the Vault's only connection to the outside world - the airlock. (With the exception of Vault 19 and Vault 87)

A Vault computer

Closed from the inside by a reinforced high-security door and from the outside by a massive, gear-shaped four-foot thick vault door (which Three Dog claimed "weighs, like, thirteen tons"), it's the only means of entering or leaving the Vault, although secondary entrances or exits may have existed in some Vaults. Vault 87 had two additional entrances reachable through Lamplight Caverns. Security codes are required to both leave and enter the Vault, and they are usually only known to a handful of people within the facility. Most vaults have a console located on both sides of the entrance, which opens the Vault door via a lever. Passwords were entered into the console likely through the speaker or via some sort of wired connection from a Pip-Boy.

The automated narrator of the the Vault-Tec vault demonstration in Washington DC's Museum of Technology states that the doors had a projected 2% failure rate in case of a direct hit by a nuclear missile. So far, the only known vault to have been hit directly (or very nearly) by a nuclear weapon is Vault 87. According to the terminal of Vault 87's overseer, the blast caused the vault's main door to completely and utterly fail, apparently damaging it "beyond repair." Though this could be considered merely a one-in-a-million freak accident and falls with that extremely small "2%", it is more likely an indicator that Vault-Tec's failure rates were completely fabricated.

Vault 15 townmap

Most Vaults use a Seal-N-Safe Vault Door Model No. 343[4] to secure the airlock, however, some older Vaults (such as Vault 101) use a different, more crude blast door model. Vault 8, the control Vault, had also a second, much larger, blast door built, that secured the entry hallway leading to the entrance to the Vault.

In addition, the Entrance level also houses the Emergency Medical Lab complete with an Auto-Doc. A Vault medic was required to be present at the EML 24 hours a day. The lab had the equipment to treat nearly all injuries and illnesses, ranging from simple bruises to irradiation.

Living Quarters

Standard pre-War design of the living quarters was that of a single room with a sanitary annex. 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. A standard level had 20,000 square feet of usable area.

The lights used in the Vaults used Simu-Sun technology, making it feel just like the outdoors, with only a fraction of a sunburn risk. The lights in Vault 101 were kept on all the time to prevent a Radroach infestation.

New Entertainertrons were used to play holotapes, and used as a slide projector in the classroom of Vault 101.

Command Center

Vault 13 Overseer Command Post

A Secret Vault Command Post

Heart of the Vault, the command center was where the Overseer's seat was located. 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 arms were stockpiled. A security guard was posted in the command center at all times, to ensure that the armaments are properly secured, and handed out only to people possessing the proper clearance from the Overseer.

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 and information, a meeting room for the dwellers and the primary store room, where the most important supplies would be stored.

The Overseer is also able to see anyone inside the Vault with the Eye-on-you cameras.

Equipped with dual 5mm miniguns in some Vaults, the Overseer's command post can be considered the last line of defense in case the Vault security is breached.

In Secret Vault, there are several command posts for the various locations. The command posts mainly contain buttons to control things like locking of doors and laser protection.


  • Vault 29 (Van Buren) was outfitted with a ZAX AI, which replaced the Overseer.
  • Vault 12 had its Overseer's room sealed due to the fact that the main door of the vault was doomed never to close.
  • East Coast Vaults (87, 92, 101, 106, 108, 112) use a different, older door mechanism (as evidenced by extensive rusting and meager safety precautions). The East Coast Vaults employ an opening mechanism that is contained entirely within the Vault itself, pulling the door inwards and simply rolling it to one side. The doors seen on West Coast Vaults, however, pull the seal outwards and use an external clamp to slide it aside.
  • East Coast Vaults lack storage rooms in the Overseer's office; they are instead located near the Atrium.
  • The Vault-Tec Secret Vault had an entirely different layout than other vaults.

True purpose

Officially, the Vaults were nuclear shelters designed to protect the American population from nuclear holocaust. However, with a population of almost 400 million by 2077, the U.S. would need nearly 400,000 Vaults the size of Vault 13, while Vault-Tec was commissioned to build only 122 such Vaults. The government, and Vault-Tec, never really believed an actual nuclear war would occur; the real reason for the existence of these Vaults was to run experiments on pre-selected segments of the population to see how they react to the stresses of isolation and how successfully they recolonize Earth after the Vault opens.

The Enclave, responsible for the experiment (officially known as the "Societal Preservation Program"), considered themselves prime candidates for recolonizing the world after a nuclear holocaust and to this end commissioned the construction of their own shelters, isolated from the Vault network. The purpose of the Vault experiments was to help prepare the Enclave for either re-colonizing Earth or colonizing another planet if Earth turned out to be uninhabitable.

The total number of vaults is a government secret and has been lost; there were the aforementioned "public" vaults, which numbered 122 and an undisclosed number of "private" vaults. Information on whether Vault-Tec was an international corporation and were there vaults made by them in other parts of the world, or were they strictly U.S. based, cannot be released due to Vault-Tec and US Government regulations[5]

Of the 122 Vaults, only 17 were control, meaning that only 17 were made to public expectations, all others were designed to include a social experiment, sometimes with a select few of the inhabitants observing the occupants.

The few Vaults that survived intact for more than 80 years came to serve another, unanticipated purpose: they were an excellent source of pure human stock, uncontaminated by the mutated airborne strain of FEV and prime candidates for conversion into super mutants.


In terms of providing safety and security for their inhabitants, most of the Vaults were complete failures. However, as noted in the Penny Arcade Comic, the Vaults were never really intended to save anyone. There was simply not enough time, money or resources to build enough shelters to house more than a fraction of the population. While the "control vaults" did function as advertised and open on schedule, most were actually intended to explore and observe how societies adapt (or fail to adapt) to various challenges and restrictions. These social experiments were performed on live and mostly unaware subjects, monitored by Vault-Tec researchers in separate facilities, and undertaken at the behest of what would become the Enclave as part of a massive feasibility study of how to best re-colonize a barren Earth or, if necessary, other planets.

Most of the Vaults seen in the games were non-viable 200 or even a mere 80 years after the War. While Vault 13 might have lasted until its scheduled opening date of 2277, the unplanned failure of the Water Chip forced the Overseer's hand and set subsequent events in motion. If Vault 101 was truly intended to stay closed "forever", its failure was inevitable; the only question was how long, and what form the change or disaster would take. Many other Vaults were abandoned because of unlivable conditions, or saw the residents driven violently insane by the procedures inflicted on them. Some of these continue to pose a hazard to the unwary who wander in from outside, looking for loot or a place of safety.

Despite all of this, the experiment may be considered a success in terms of the data collected... data that was much more important to the Vault-Tec and Enclave scientists than a few hundred thousand lives, most of whom would have died anyway if not for the Vaults.

List of known Vaults

Designation Description/Fate Location Appearances
LA Vault The Vault-Tec demonstration Vault. It was not part of the experiment, and was the Master's Vault under the Cathedral in Fallout. Southern California, near Los Angeles (Cathedral) Fallout
Vault 3 A control Vault designed to open after 20 years, but kept closed longer due to the wishes of the vault inhabitants. However, an unplanned water leak forced the occupants to open in hopes of trading with the outside. Unfortunately, all of the vault's residents were massacred by a group of raiders known as the Fiends shortly after they opened the vault door. Mojave Wasteland Fallout: New Vegas
Vault 6 Unknown. Mount St. Helens, Washington Fallout Extreme


Vault 8 A control Vault, intended to open and recolonize the surface after 10 years and is equipped with a GECK. Vault City is the result. Northern Nevada
(Vault City)
Fallout 2
Vault 11 This Vault was a social experiment testing human nature - most specifically the ability to sacrifice oneself for others, and the ability to place ideals above one's own life. Mojave Wasteland Fallout: New Vegas
Vault 12 In order to study the effects of radiation on the selected population, the Vault Door was designed not to close. This is the Necropolis Vault and a large population of ghouls was the result. Bakersfield
Vault 13 Intended to stay closed for 200 years as a study of prolonged isolation, the broken water chip forced the Overseer to improvise and use the Vault Dweller as a pawn. Later study of the Vault 13 records by the Enclave led them to their current plan to end the war. Southern California Fallout
Fallout 2
Vault 15 Intended to stay closed for 50 years and include people of radically diverse ideologies. Gathered from what you hear from Aradesh in Fallout, he has quite a bit of multicultural flavoring to his speech. The birthplace of three raider groups and Shady Sands (later to become the NCR). Southern California Fallout
Fallout 2
Vault 17 The Vault was raided in 2154 and its inhabitants taken prisoner by the Master's Army. They were subsequently turned into Super Mutants. Unknown Fallout: New Vegas (mentioned-only)
Vault 19 The Vault was segregated into two groups, 'Red' and 'Blue'. The groups lived in separate sections of the vault and the inhabitants may have been chosen due to pre-existing paranoia. Mojave Wasteland Fallout: New Vegas
Vault 21 This Vault's purpose was gambling, reinforced by having only compulsive gamblers admitted as Vault residents, and with all conflicts within the Vault to be resolved through gambling. It is one of the few non-control vaults that didn't end in failure. Mojave Wasteland (New Vegas) Fallout: New Vegas
Vault 22 Apparently a Vault designed with agriculture as its primary purpose. Successful experiments where executed in creating strains of plants that could grow under artificial light. However, an experiment on pest control involving a genetically-manufactured spore annihilated the Vault's inhabitants. Mojave Wasteland Fallout: New Vegas
Vault 24 Unknown, any information in existence is based off cut content for a Vault suit. Unknown
(Mojave Wasteland?)
Fallout: New Vegas
(cut content)
Vault 27 This Vault would be overcrowded deliberately. 2000 people would be assigned to enter, double the total sustainable amount. Unknown Fallout Bible only
Vault 29 No one in this Vault was over the age of 15 when they entered. Parents were redirected to other Vaults on purpose. Harold is believed to have come from this Vault. Colorado Fallout Bible (first mentioned)
Van Buren
Vault 34 The armory was overstocked with weapons and ammo and not provided with a lock. The Boomers, the weapon-crazy inhabitants of Nellis Air Force Base, descend from the inhabitants of this Vault. Mojave Wasteland Fallout Bible (first mentioned)
Fallout: New Vegas
Vault 36 The food extruders were designed to produce only a thin, watery gruel. Unknown Fallout Bible only
Vault 39 Unknown. Abilene, Texas Fallout: Brotherhood of Steel 2


Vault 42 No light bulbs of more than 40 watts were provided. Unknown Fallout Bible only
Vault 43 Populated by twenty men, ten women, and one panther. Unknown Penny Arcade


Vault 53 Most of the equipment was designed to break down every few months. While repairable, the breakdowns were intended to stress the inhabitants unduly. Unknown Fallout Bible and Possibly on Vault-Tec east coast computers
Vault 55 All entertainment tapes were removed. Unknown Fallout Bible only
Vault 56 All entertainment tapes were removed except those of one particularly bad comic actor. Sociologists predicted failure before Vault 55. Unknown Fallout Bible only
Vault 68 Of the one thousand people who entered, there was only one woman. Unknown Fallout Bible
and possibly in conversation with President Richardson.
Vault 69 Of the one thousand people who entered, there was only one man. Unknown Fallout Bible (first mentioned)
Penny Arcade
Van Buren concept art
and possibly in conversation with President Richardson.
Vault 70 All jumpsuit extruders fail after 6 months. Most of the inhabitants were Mormons. The city of New Canaan was founded by the vault dwellers after they left the vault. Salt Lake City, Utah Fallout Bible 0

Van Buren

Vault 74 A very small vault consisting only of the Overseer's office, atrium, clinic, and quarters (blocked). Capital Wasteland Fallout 3 modding tutorial[9]
Vault 76 This Vault was designed as a control group for the vault experiment like Vault 8, intended to open and re-colonize the surface after 20 years. Unknown
(Capital Wasteland?)
Mentioned in Fallout 3
Vault 77 Populated by one man and a crate full of puppets. In Fallout 3 a vault 77 jumpsuit is acquirable at Paradise Falls. Unknown Penny Arcade
Vault 87 A Forced Evolutionary Virus research facility Capital Wasteland Fallout 3
Vault 92 Populated largely by renowned musicians, this vault was a test bed for a white noise-based system for implanting combat-oriented posthypnotic suggestions. Capital Wasteland Fallout 3
Vault 100 Unknown Mentioned in Fallout 3 game files with a unused Vault 100 jumpsuit icon. Fallout 3
Vault 101 Evaluation of performance of an omnipotent Overseer in a closed community Capital Wasteland Fallout 3
Vault 106 Psychoactive drugs were released into the air filtration system 10 days after the door was sealed. Capital Wasteland Fallout Bible (first mention)
Fallout 3
Vault 108 The vault houses a cloning lab and all (surviving) residents are clones of one man called Gary. Capital Wasteland Fallout 3
Vault 112 Home of Tranquility Lane virtual reality simulator. Capital Wasteland Fallout 3
Unfinished Vault A fenced construction place in a small cave north from Vaults 13 and 15. Northern California Fallout 2
Vault 0 A special Vault designed to "monitor and control" other Vaults. Cheyenne Mountain (Colorado) Fallout Tactics


Secret Vault A secret Vault dedicated to protect high-members of Vault-Tec and used to research the latest technologies and the Forced Evolutionary Virus. Los Fallout: Brotherhood of Steel


Vault Prototype A small Vault-Tec facility used as the base of operations by the Brotherhood of Steel Texas Fallout: Brotherhood of Steel


Burkittsville Vault An unnamed Vault near Burkittsville mentioned in the Hamilton's Hideaway terminal entries. The inhabitants are cannibals, wear the skins of those they kill, and ambush people attempting to reach the Vault. Unknown. Fallout 3 cut content

Other installations using Vault-Tec technology


Behind the scenes

The vault experiment was an idea created by Tim Cain during the initial stages of Fallout 2 development.

Icon cut content.pngThe following is based on Fallout 2 cut content and has not been confirmed by canon sources.

Vault control room

The developers intended for the player to first encounter information about the Vault Experiment as they read the Vault 8 records in Fallout 2. They could discover a classified file (opened with a successful Science skill roll) explaining the purpose of Vault 8 was to be a "control Vault," designed to hold 1000 people and open at a designated time. This file was intended to foreshadow the discovery of the true and sinister purpose of the Vaults.

The player was also intended[13] to apply his Science skill to the central computer in Vault 13 to obtain a history of Vault 13, the Overseer's involvement in the Vault Dweller's expulsion, and even worse, the true purposes of the Vaults. The Overseer was conscious of the true purpose of the Vaults as social experiments on a grand scale, and consequently drove out the Vault Dweller because of fear he would ruin the experiment... or uncover it.

Icon cut content.pngEnd of information based on Fallout 2 cut content.


In the Vault-Tec Headquarters, a Vault door can be seen hanging from the ceiling to the right of the lobby. It is a copy of the Vault 101 door, right down to the number on the center.

There is another vault exhibit in Washington D.C. inside the Museum of Technology. The number on the door is 106. This one however, though containing the same materials for walls and lighting is only one corridor with vault doors at either side always kept open for the museum visitors to take the tour. Just like Vaults 87, 92, 106, and 108 the metal walls have rusted over time. It's safe to say this "vault" did not work as halfway through the corridor, a burnt skeleton of a janitor can be seen on the floor showing that they were killed by the bombs.


Most of the above comes from:


  1. Fallout Bible 0
  2. Dialogue with Liz, the Tap House bartender, who mentions that VC gets the uranium for their reactor from Broken Hills
  3. Vault 101 Announcement system: "Did you know - the average life expectancy of a resident in a properly maintained vault is 92.3 years?"
  4. from Fallout
  5. Interview with Chris Taylor at Vault 13.net
  6. The canceled Fallout Extreme is non-canon.
  7. The canceled Fallout: Brotherhood of Steel 2 is non-canon.
  8. Note that this comic, while official and created in cooperation with Emil Pagliarulo, has not been stated to be canon (nor non-canon).
  9. Vault 74 tutorial in the GECK wiki. This Vault is likely not canon, but is included on the list as the tutorial is official and made by a Bethesda designer.
  10. Fallout Tactics is not considered to be entirely canon and Vault 0 is not entirely consistent with the Vault Experiment, although there are possible explanations for the apparent inconsistency.
  11. 11.0 11.1 Fallout: Brotherhood of Steel is not canon.
  12. similar, but not the same descriptions as at Fallout Bible
  13. Fallout Bible 0
Vault-Tec vaults
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