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DOOM 3 Hints

Where can I get the access card for the door in Environmental Monitoring?

  • 1 of 4: There's another door on the same level, and it's unlocked. Try it.
  • 2 of 4: Go around and climb up the ladder to get to the Thermal Regulation Pump area.
  • 3 of 4: Once you're on the bottom floor of the pump area, jump over some pipes to get to an alcove with some ammo.
  • 4 of 4: From there, crawl under a large pipe to find J. Katayama and the keycard you're after.