WHAT IS GAUGE PRESSURE?

Gauge pressure is the pressure measured relative to the ambient atmospheric pressure. Gauge pressure can be measured using a diaphragm sensor, where one side of the diaphragm is exposed to the pressure media that is to be measured, while the other side is exposed to the ambient atmospheric pressure.

When measuring gauge pressure, it should be noted that the measured gauge pressure will change with variations in barometric pressure due to changes in weather patterns, unless the measuring point is itself exposed to ambient atmospheric pressure.

In vacuum applications, gauge pressure measurement and control can be used to accurately ventilate a vacuum chamber to atmospheric pressure and prevent particulate contamination when opening to the atmosphere. Such practice is also used in semiconductor load lock applications.