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mmHg - Millimetres of Mercury at 0 deg C Pressure Unit
Millimeters of Mercury at a temperature of zero degrees Celsius is a small Metric pressure unit which is derived from the hydrostatic pressure generated by a 1 mm tall column of mercury liquid. 1 Millimeter of Mercury equals 133.322 Pascals.
The mmHg pressure unit is mostly used in medical industry particularly for measuring blood pressure where tradionally a liquid manometer was used as part of blood pressure testing equipment. Electronic means of measuring blood pressure are now more commonplace but the units continues to be used by the medical profession.
The pressure that is generated by a fixed height of mercury which will vary depending on the ambient temperature and local gravity, therefore it is not an absolute pressure conversion and the preferred reference values of temperature and density can vary from country to country. The conversion factors listed below are derived from mercury with a density of 13,595.1 kg/m³ and a local gravity of 9.80665 m/s².
Please use the table below to find conversion factors in other units for 1 Millimetre of Mercury.
To convert into mmHg from other pressure units please follow the relevant link below.
Multiple calculations can be conducted easily using our online pressure conversion tool.
See how mmHg is calculated from SI units or check the various forms of writing mmHg.
| 0.00133322 | bar |
| 0.0193368 | psi |
| 1.33322 | mbar |
| 133.322 | N/m² |
| 133.322 | Pa |
| 1.33322 | hPa |
| 0.133322 | kPa |
| 0.000133322 | MPa |
| 0.00135951 | kg/cm² |
| 13.5951 | mmH2O 4°C (39.2°F) |
| 1.35951 | cmH2O 4°C (39.2°F) |
| 0.0135951 | mH2O 4°C (39.2°F) |
| 0.535240 | inH2O 4°C (39.2°F) |
| 0.0446033 | ftH2O 4°C (39.2°F) |
| 1 | mmHg 0°C (32°F) |
| 0.1 | cmHg 0°C (32°F) |
| 0.0393701 | inHg 0°C (32°F) |
| 1.000000 | Torr |
| 1000.000 | mTorr |
| 0.00131579 | atm |
| 0.00135951 | at |
| 1333.22 | dyn/cm² |
| 0.309388 | oz/in² |
| 1000 | µHg 0°C (32°F) |
| 0.00000863249 | tsi (uk, long) |
| 0.00000966839 | tsi (usa, short) |
| 0.00139225 | tsf (usa, short) |
| 2.78450 | psf |
| 1.35951 | g/cm² |
Please note that the conversion factors above are accurate to 6 significant figures.
Formula
Pressure = Force / Area
Force = Mass x Acceleration
Mass = Density x Volume
Volume = Area x Height
Acceleration = Distance / (Second x Second)
SI Units
Mass: Kilogram (kg)
Distance: Metre (m)
Time: Second (s)
Force: Newton (N)
Pressure: Pascal (Pa)
Input Values
Density = Mercury Density at 0degC = 13595.1 kg/m³
Area = 1 m²
Height = 1 mm = 0.001 m
Acceleration = Standard Gravity = 9.80665 m/s²
Calculation
1 mmHg Mass = 13595.1 kg/m³ x 1 m² x 0.001 m = 13.5951 kg
1 mmHg Force = 13.5951 kg x 9.80665 m/s² = 133.3223874 N
1 mmHg Pressure = 133.3223874 N / 1 m² = 133.3223874 Pa
These are the different versions used for identifying mmHg that you may find elsewhere.
Millimetres of Mercury
Millimeters of Mercury
Millimetres of Mercury Column
Millimeters of Mercury Column
mmHg
mm Hg
Site Last Updated: 09/02/12
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