Vacuum

A vacuum was an area that was virtually empty of matter. The most commonly known was that of space. Most life forms could not survive in a vacuum for very long.

There were, however, those who were able to survive in the vacuum of space indefinitely or for extended periods of time. These included:
 * Time Lords, for limited periods (DW: Four to Doomsday, TARDIS)
 * Daleks (DW: The Parting of the Ways)
 * Cybermen (DW: The Moonbase)
 * Olympians (DWM: The Life Bringer)
 * Sensorites (DW: The Sensorites)
 * Wirrn, for amounts of years (DW: The Ark in Space)
 * Toby Zed, whilst possessed by the Beast (DW: The Impossible Planet)
 * Star Whales (DW: The Beast Below)
 * Ahab (K9TV: The Bounty Hunter)

Individuals killed by exposure to vacuum

 * Katarina (DW: The Daleks' Master Plan)
 * Kirksen (DW: The Daleks' Master Plan)
 * Varan (DW: The Mutants)
 * Lynda Moss (DW: The Parting of the Ways)
 * Scooti Manista (DW: The Impossible Planet)
 * Chief Steward (DW: Voyage of the Damned)