Logo of the Physikalisch-Technische Bundesanstalt


Working Group 3.33

Realisation of the pressure scale

On the basis of the laws of physics, standard devices used for the realisation of the pressure scale allow pressure values to be determined from:

  • measured values of SI base units such as length, mass, temperature;
  • values of material constants, such as density, expansion coefficients;
  • natural constants such as acceleration due to local gravity;
  • measured values of influencing quantities such as air pressure and ambient temperature.

Standard devices for the realisation of the pressure scale are validated within the scope of international comparisons between national metrology institutes (Opens external link in new windowinfo).

Survey of the measuring ranges of standard instruments

Standard device

Measuring range

Pressure mode






Mercury precision manometer

180 kPa




Diving bell manometer

4 kPa




Pressure balance with digital display

7 kPa




Pressure balance

5 kPa

7 MPa
80 MPa




Twin pressure balance for differential pressure measurement in gases

80 MPa
pline: 80 MPa




Liquid column for differential pressure measurement in gases; manometric liquid: Water

10 kPa
pline: 14 MPa




Pressure balance; oil operated

0,2 MPa

1 GPa





1,4 GPa





The international admitted measurements are published in the database of International Bureau of Weights and Measures (Opens external link in new windowBIPM).