Bar (unit)

A bar is a unit of pressure, nearly identical to the atmosphere. One bar is equal to 100 kilopascals.

Starfleet space suits measure oxygen pressure in millibars. 

Comparative list of pressures

 * 1,000 millibars = 1 bar:


 * The computer warned Tom Paris that his space suit was leaking, informing him that the oxygen level was dropping from 114 millibars to 93 millibars before B'Elanna Torres connected to his suit to share her oxygen.


 * While Paris and Torres shared their oxygen, the level dropped from 104 millibars, to 87 millibars, and finally to 71 millibars, before they were rescued by USS Voyager.


 * While traveling to orbit in an mag-lev carriage, Neelix noted that while at an altitude of 800 meters, the carriage was traveling at a velocity thirty kilometers per hour and the internal atmospheric pressure was at 700 millibars.


 * The atmosphere at the surface of an unnamed planet which was home to a species of rock creatures was recorded at 800 millibars.


 * Capped deuterium well heads were under 5,000 millibars of pressure.