Measurement Units of Vacuum Data
The units pascal [Pa], kilopascal [kPa], bar [bar] and millibar [mbar] are most widely used in vacuum technology as units for pressure. The units are converted as follows:
0.001 bar = 0.1 kPa = 1 mbar = 100 Pa
On this website, all absolute pressure values are given in bar or mbar, all relative values in %. The % value is typical for a relative indication of the efficiency of a vacuum generator. Other units are used internationally. Some of them are included in the following table.
Vacuum/pressure conversion table
| bar | N/cm2 | kPa | atm, kp/cm2 | mm H2O | Torr; mm Hg | in Hg | |
|---|---|---|---|---|---|---|---|
| bar | 1.00000 | 10.00000 | 100.0000 | 1.01970 | 10,197.00 | 750.0600 | 29.5400 |
| N/cm2 | 0.10000 | 1.00000 | 10.0000 | 0.10190 | 1,019.70 | 75.0060 | 2.9540 |
| kPa | 0.01000 | 0.10000 | 1.0000 | 0.01020 | 101.97 | 7.5006 | 0.2954 |
| atm, kp/cm2 | 0.98070 | 9.80700 | 98.0700 | 1.00000 | 10,332.00 | 735.5600 | 28.9700 |
| mm H2O | 0.00010 | 0.00100 | 0.0100 | 0.00009 | 1.00 | 0.0740 | 0.0030 |
| Torr; mm Hg | 0.00133 | 0.01333 | 0.1333 | 0.00136 | 13.60 | 1.0000 | 0.0394 |
| in Hg | 0.03380 | 0.33850 | 3.8850 | 0.03446 | 345.40 | 25.2500 | 1.0000 |
