| | ISA | Getting a grip on humidity |
 | | If we consider air, this means the total atmospheric pressure of 1.013 bars (14.7 pounds per square inch absolute) is the sum of the partial pressures of all its constituents: nitrogen, oxygen, water vapor, argon, carbon dioxide, and various other gases in trace amounts. |
 | | If saturation vapor pressure has occurred in air or a gas mixture, introducing additional water vapor requires that an equal amount of water vapor condense out of the mixture as a liquid or solid. |
 | | Vapor pressure tables also enable one to look up the saturation vapor pressure for any temperature, and of course there are a number of water vapor calculation programs available for PCs. |
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