Pressure is an important parameter in instrumentation.

The unit of pressure commonly used in the industry is the bar.

One bar equals 100000 Pascal. One pascal equals one Newton per sq. meter.

One bar is also equal to 1.01 kg/cm ^{2} .

Sometimes, differential pressure is measured in mm of water column,

The formula for converting pressure from mm.h2o to bar is as follows

Pressure in bar_{ }= 9.806648601 � 10^{-5} � Pressure in H_{2}o