The Vault - Fallout Wiki

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The Vault - Fallout Wiki
The Vault - Fallout Wiki
Mentioned-only character
Karl Oslow
Biography and appearance
AffiliationMass Fusion
RoleFounder and CEO
Dialogue FileKarl Oslow's dialogue
Mentioned inFallout 4

Karl Oslow was the founder of Mass Fusion and its CEO until the Great War.


Before starting Mass Fusion, Oslow was a Poseidon Energy scientist. For six years, 2037 to 2043, he worked for the megacorporation, perfecting their technology, only to see it sold to the military and used to hurt people. He left the company in 2043, to create his own, clean company.[1] Its flagship product would be energy, provided through Oslow's Cleanpower Initiative. By 2053 his research efforts bore fruit, as the first "fusion" distribution boxes and sources of power entered the market. Through cunning and dedication, Oslow eventually cornered the energy market in Massachusetts, becoming the primary power provider for the state by 2070.[2][3]

One small problem with Oslow's Cleanpower was that it was power, but it wasn't clean. The junction boxes and plutonium wells were all fundamentally fission-based, provided with lead shielding to protect the users from irradiation. Unfortunately, imperfect shielding was all too common and radiation poisoning was a real risk among consumers. The company, of course, vehemently denied these accusations.[4] It wasn't until 2066 and the unveiling of the first power armor fusion cell[5] that the company truly started providing fusion power, but even then, legacy infrastructure was too commonplace to be cheaply replaced. Mass Fusion continued to operate containment facilities[6] and dumping grounds in rural Massachusetts, hiding the radioactive waste from prying eyes.[7]

In the meantime, Oslow worked with Noel Chandrich to create a true fusion reactor. What originally started as a civilian project quickly turned to military applications as jingoism awoke in Oslow. He clashed with Chandrich over his contacts with the military and the intention to hand the beryllium agitator over to them for use in weapons of war. Most importantly, Oslow forced the project to accelerate, ignoring problems with shielding. As Oslow fumed, Kathy Hathaway discovered a breakthrough in June: Graphene could help resolve the shielding issues.[8] Her composite alloy allowed Chandrich to get the agitator online[9] and on July 29, the switch was thrown.[10]

Chandrich advised Oslow to reconsider deepening his ties with the military, but the CEO's mind was made up.[1] After verifying that the reactor does, indeed, work as advertised, Oslow fired Chandrich at the beginning September.[11]

To cripple his career, Oslow ensured a binding non-compete agreement was signed and froze his pension and contracts to boot. Truly, he became what he most despised: A jingoist capitalist. Just like Poseidon.[12]


Karl Oslow is mentioned only in Fallout 4.


  1. 1.0 1.1 Mass Fusion building terminals; Executive Research Lab Terminal, Personal IntraMail 07-30-77: "To: K. Oslow
    From: N. Chandrich, Research Lead
    As per your instructions, the Beryllium Agitator has been installed in our primary reactor on sub-level 01. I've also increased security on all of the keyreaders in the building, so you'll need your executive keycard handy if you want to use any of the elevators.
    I'd like to go on official record that I am opposed to accelerating the project's schedule. I find it disturbing that current events (e.g. global unrest) hasn't had an effect on your decision. While I realize your recent contact with the U.S. Military may be making it difficult to follow a rational course of action, I strongly urge you to reconsider.
    I thought this is exactly why you left Poseidon, Karl."
  2. Mass Fusion building terminals; Customer Service Terminal, Company History: "In the spring of 2043, Karl Oslow dared to dream of limitless power being supplied to countless homes from a single power plant. After spending six years years cutting his teeth as an electrical engineer with Poseidon Energy, Mr. Oslow decided he'd had enough with traditional methods of energy distribution and founded Mass Fusion to begin realizing his vision.
    After only a decade of research, Mass Fusion's Cleanpower Initiative transitioned from dream to reality and the switches were thrown. The people of Boston embraced this new technology, and by 2070, Mass Fusion became the primary power provider for all of Massachusetts. Now, as we look to the future, Mass Fusion hopes to bring ten more power plants online in the next several decades.
    To open a new account and begin enjoying the benefits of your nuclear tomorrow, please see one of our Mass Fusion Customer Service Representatives today!"
  3. Fallout 4 loading screen hints: "Before the Great War, Mass Fusion was Boston's premiere utility, providing power to all of Massachusetts."
  4. Mass Fusion building terminals; Customer Service Terminal, I'm Feeling Sick: "Many individuals assume that the fusion distribution box in their home may present a danger to its occupants. While the device gives off a trace amount of radiation, we can assure you that it's completely safe. If you're experiencing the following symptoms, we give you our word you that they are in no way related to our Cleanpower technology: Nausea, vomiting, diarrhea, headache, fever, dizziness and disorientation, weakness, fatigue, hair loss, poor wound healing, low blood pressure, skin flaking or burns."
  5. Fallout Bible 0: "2066 Summer Adding further insult to the Chinese-American relations, the first crude fusion cell is unveiled, one of the results of the Power Armor project. Devices designed for the fusion cell begin to be manufactured. Incorporating fusion power into the general US infrastructure begins, but the process is too slow to supply power to the regions that need it. Nearly thirteen years later, few sections of the United States were supplied with fusion power."
  6. Fallout 4 Vault Dweller's Survival Guide Collector's Edition p.281: "[2.13] Mass Fusion Containment Shed
    Mass Fusion is the leader in the safe handling and disposal of radioactive waste. Except here the place is overrun with Feral Ghouls and spilled barrels. Check the outside balcony for a cooler (Novice). Inspect the supervisor’s terminal (Novice) to unlock the security door. Check the secure area for a toolbox (Novice) and a gate to a steamer trunk."
    (Fallout 4 Vault Dweller's Survival Guide Map)
  7. Fallout 4 Vault Dweller's Survival Guide Collector's Edition p.355: "[5.06] Mass Fusion Disposal Site
    This was the property of Mass Fusion and used as a disposal site for coolants and other liquids. As much of the poisons were buried at this site, pressure has built up and the irradiated pools around the shores of the lake have bubbling gasses. Be wise: Wear radioactive protective gear at all times. Be perceptive: Locate the steamer trunk in the treehouse to the northeast. Be extra perceptive: There’s a Mini Nuke inside the large tire by the yellow digging machine."
    (Fallout 4 Vault Dweller's Survival Guide Map)
  8. Mass Fusion building terminals; Product Development Terminal, Research Intramail 06-20-77: "To: K. Hathaway, Materials Division
    From: N. Chandrich, Research Lead
    Kathy, I just wanted to let you know that your work on the Agitator has been invaluable. The shielding has always been a problem, but the use of graphene in the alloy was a stroke of genius. I just wanted to let you know that I'll be recommending you for a promotion this year. Good work."
  9. Mass Fusion building terminals; Product Development Terminal, Research Intramail 07-22-77: "To: K. Hathaway, Materials Division
    From: N. Chandrich, Research Lead
    Kathy, would it be possible to get a full sheet of your composite alloy within the next week? Karl's pressuring me to get the Beryllium Agitator online by the end of the month or "heads are going to roll." If you run into any problems, let me know."
  10. Mass Fusion building terminals; Product Development Terminal, Research Intramail 07-29-77: "To: K. Hathaway, Materials Division
    From: N. Chandrich, Research Lead
    You're a miracle worker, Kathy! The graphene composite shielding was the last component holding us back from getting the Agitator online, and you got it done in less than a week. I don't know how I could have done this without you! Another job well done. Keep this up and you'll be a development lead in no time."
  11. Mass Fusion building terminals; Executive Research Lab Terminal, Personal IntraMail 08-29-77: "To: K. Oslow
    From: N. Chandrich, Research Lead
    I've been monitoring the reactor for weeks now, and the Beryllium Agitator is running at peak efficiency. In fact, I've only detected an EM spectrum decay of less than a thousandth of a percent. If you were hoping for a stable plasma reaction, it looks like you've found it. Congratulations. Perhaps you and the military should open a bottle of champagne together."
  12. Mass Fusion building terminals; Executive Research Lab Terminal, Personal IntraMail 09-05-77: "To: K. Oslow
    From: T. Reisenbaur, HR Coordinator
    As of this morning, Dr. Noel Chandrich was escorted from the building, and his contract with Mass Fusion has been terminated. His terminal's memory has been wiped, and all of his research transferred to our mainframe. Dr. Chandrich has been made aware that any attempt to seek employment at a rival nuclear power company will result in a lawsuit. As per his contract, his pension and benefits are now frozen. If there's anything else you need from HR, please let me know."