Pressure calibration requires the output reading of the instrument being calibrated to be compared with the output reading of a reference standard instrument when the same pressure is applied to both.

It is important as it promotes efficiency and safety while ensuring standardisation. The sensor you are using for that information should be calibrated to guarantee the pressure measurement is accurate and falls within the tolerance you deem acceptable if you need to know the pressure of a process or environmental state. If not, you can't be sure the accuracy of the pressure reading is good enough for your needs.