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 (info).
Survey of the measuring ranges of standard instruments
Standard device | Measuring range | Pressure mode | |||
from | to | pabs | pe | Δp | |
180 kPa | + | + | + | ||
4 kPa |
| + | + | ||
7 kPa | + | + |
| ||
5 kPa | 7 MPa | + | + |
| |
Twin pressure balance for differential pressure measurement in gases | 80 MPa |
|
| + | |
Liquid column for differential pressure measurement in gases; manometric liquid: Water | 10 kPa |
|
| + | |
Pressure balance; oil operated | 0,2 MPa | 1 GPa |
| + |
|
Manganin-Manometer | 1,4 GPa |
| + |
|
The international admitted measurements are published in the database of International Bureau of Weights and Measures (BIPM).