In Fallout, people become ghouls when they receive a massive non‑lethal dose of radiation that mutates their bodies instead of killing them, often leaving them hairless, decayed-looking, but functionally immortal.

What a ghoul is

  • Ghouls are humans (and occasionally other creatures) who survived heavy radiation and were transformed rather than dying.
  • They usually gain extremely long lifespans, resistance or immunity to further radiation, and, in many cases, accelerated healing.

How ghoulification happens (lore)

In general Fallout lore (games + TV show):

  • The core requirement is intense radiation exposure delivered in a way that doesn’t immediately kill the subject; a fatal dose still just results in death.
  • This can happen in different ways: direct blast from nukes, long-term exposure in highly irradiated zones, or experimental radioactive chemicals/drugs that combine radiation with other compounds.

Over time, the skin sloughs away, hair is lost, and the person ends up with the classic “rotting but alive” look, while remaining conscious and often mentally intact.

In Fallout 76 (playable ghoul)

If you’re asking “how do you become a ghoul in Fallout” as a player, the only mainline game that lets you do this directly is Fallout 76 with the ghoulification update:

  • You must reach level 50, which unlocks the main quest “The Leap of Faith” in your log.
  • This quest leads you to a character named Leamon Price and then to Parthenia, a ghoul scientist who offers a ghoulification procedure tied to irradiated ore from Emmett Mountain.

After finishing “The Leap of Faith,” you unlock “A Fresh Pair of Genes,” where Parthenia offers to turn you into a ghoul:

  1. Agree to undergo the procedure in her lab.
  1. Use the inhaler device she sets up, then walk into the nearby missile silo area, where your character succumbs to controlled radiation poisoning.
  1. You wake up as a ghoul and can customize your new ghoul appearance before returning to normal play.

Effects of becoming a ghoul (76)

When you ghoulify your character in Fallout 76:

  • You gain ghoul traits like using radiation as a positive resource (healing and powering you up instead of just damaging you), while still needing to watch for other forms of damage.
  • NPCs and some factions will react differently, and certain areas or interactions may require disguises to be treated like a normal human.

Lore vs “rules” for becoming a ghoul

Fans often note there is no strict, universally consistent “formula” for ghoulification across every game and story:

  • Some characters become ghouls after surviving the Great War’s initial blasts; others gradually change from long-term radiation exposure or experiments with radioactive chemicals.
  • Community discussions generally agree on one key point: radiation is always the essential ingredient, while the exact dose, timing, and conditions vary from case to case.

TL;DR: In Fallout lore, you become a ghoul by surviving a huge but not instantly fatal dose of radiation, and in Fallout 76 specifically you unlock and complete the “Leap of Faith” and “A Fresh Pair of Genes” quests at level 50 to turn your player character into a ghoul.

Information gathered from public forums or data available on the internet and portrayed here.