Pressure Measuring Devices Pressure Pressure is the force acting per unit area and it is expressed mathematically as pressure equal to the force divided by the area and the unit of pressure is newton per meter squared and newton per meter squared is also called pascal. And common types of pressure are atmospheric pressure, absolute pressure, vacuum pressure, gauge pressure. Common units of pressure are pascal, kilogram per square centimeter, bar, pound per square inch or psi, mmh2o, mmhg, inh2o, inhg. P = Force(F)/ Area(A) , pascal (N/m²) Pressure measuring devices Pressure measuring instruments are barometer, manometer, pressure tube, diaphragm pressure gauge 1. Barometer A barometer is a device that measures atmospheric pressure and common types of barometers are digital barometers, water barometers and mercury barometers. 1. Digital Barometer Digital barometer is the most common barometer for measuring pressure and Digital barometer is used for micro chip or IC to measure air press