Pressure
Convert millimetre of mercury (mmHg) to kilopascal (kPa). Pressure is force per unit area. Process engineers move constantly between SI (kPa, bar) and US (psi) units, and between absolute and gauge.
1 mmHg = 0.1333224 kPa
To convert millimetre of mercury to kilopascal, multiply the mmHg value by 0.1333224. To go the other way, divide by 0.1333224 (or multiply by 7.500616).
| mmHg | kPa |
|---|---|
| 1 | 0.1333224 |
| 2 | 0.2666448 |
| 5 | 0.6666119 |
| 10 | 1.333224 |
| 25 | 3.33306 |
| 50 | 6.666119 |
| 100 | 13.33224 |
| 250 | 33.3306 |
| 500 | 66.66119 |
| 1000 | 133.3224 |
Line and vessel ratings, pump discharge heads, and relief set points are all specified in pressure units — usually psi or barg in the field and kPa in calculations.
Always track whether a value is absolute or gauge: 0 barg equals about 101.3 kPa absolute, and mixing the two is a common and costly error.
Worked example. A pressure of 7500.616 mmHg is 1000 kPa.
Multiply the value in mmHg by 0.1333224 to get kPa. For example, 10 mmHg = 1.333224 kPa.
1 mmHg equals 0.1333224 kPa.
Line and vessel ratings, pump discharge heads, and relief set points are all specified in pressure units — usually psi or barg in the field and kPa in calculations.