Standard Atmosphere

The unit "1 Standard Atmosphere" is defined as the pressure equivalent to that exerted by a 760 mm column of mercury at 0^oC (32^oF) at sea level, and at standard gravity (32.174 ft/sec2). Atmospheric pressure is the weight of a column of air per area unit as measured from the top of the atmosphere to the reference point being measured. Atmospheric pressure decreases as altitude increases.

Equivalents to 1 atmosphere are as follows:

     76 centimetres (760 mm) of mercury

     29.921 inches of mercury

     10.3322 metres of water

     406.782 inches of water

     33.899 feet of water

     14.696 pounds-force per square inch

     2,116.2 pounds-force per square foot

     1.033 kilograms-force per square centimetre

     101.325 kilopascals