Pressure is usually measured, either as absolute pressure (psia), or relative to atmospheric pressure (psig).
Such measurements are called gauge pressure. An example of this is the air pressure in a car tire, which might be said to be "35 psi," but is actually 35 psi above
atmospheric pressure. Since atmospheric pressure at sea level is about 14.7 psia, the absolute pressure in the tire is therefore about 49.7 psi.
Atmospheric pressure is the pressure exerted by the air around us. The pressure varies both with altitude, and weather patterns.
Standard atmospheric pressure at sea level is defined as 1 atmosphere equal to 760 millimeters of mercury (760 Torr) and 101,325 Pascals.
29 117/127 inches of mercury 29.92 inHg 14.6959 psia or 0 psig (pounds-force per square inch, absolute or gauge lbf/in 2
The total pressure exerted on a system, equal to the gauge pressure plus atmospheric pressure. (psia)
The pressure of a system measured by a gauge, which excludes atmospheric pressure. (psig)
PTC Metrology will notify you by email when your instrument is due for recalibration, in accordance with the period of validity that your quality system specifies.
Please register your instrument today.
Our certificate number 1896.01 from A2LA also covers calibration of: