Micron or Micrometre of Mercury is a very small pressure unit which is derived from the pressure due to gravity that is generated by a 1 micrometer (1/1000mm) column of liquid mercury. 1 micron of mercury of mercury at zero degrees Celsius equals 0.133322 pascals.

The main use for micrometers of mercury is to measure high vacuum.

The micron of Hg pressure unit is treated as being equal to 1 millitorr, however although the mtorr is a fixed value, the mercury measurement can vary slightly around the world depending what is assumed for the density of mercury and local gravity.

For more information on how Mercury units are derived, please go to our mmHg web page.

Pick a pressure unit conversion factor from the list below for the equivalent value of 1 micron Hg.

Click one one of the units below to find the conversion value to microns of Hg.

Generate many different unit conversions and values of micrometres of Hg using our webpage pressure converter.

View the derivation of µHg from SI units or check a pressure unit against the various ways of describing µHg.

**Low pressure measurement products**

- Solvent compatible +/-100mWG dp transmitter with PTFE seals
- 20 Pa DP range 0-10V output air pressure sensor for building management use
- Using 25 mbar DP sensor on vacuum below 0.2 bar absolute
- 100 mbar gauge range 0-5 volts output stainless steel pressure sensor

## Conversion Factors

- 0.00000133322 bar
- 0.0000193368 psi
- 0.00133322 mbar
- 0.133322 N/m²
- 0.133322 Pa
- 0.00133322 hPa
- 0.000133322 kPa
- 0.000000133322 MPa
- 0.00000135951 kg/cm²
- 0.0135951 mmH2O 4°C (39.2°F)
- 0.00135951 cmH2O 4°C (39.2°F)
- 0.0000135951 mH2O 4°C (39.2°F)
- 0.000535240 inH2O 4°C (39.2°F)
- 0.0000446033 ftH2O 4°C (39.2°F)
- 0.001 mmHg 0°C (32°F)
- 0.0001 cmHg 0°C (32°F)
- 0.0000393701 inHg 0°C (32°F)
- 0.001000000 Torr
- 1.000000 mTorr
- 0.00000131579 atm
- 0.00000135951 at
- 1.33322 dyn/cm²
- 0.000309388 oz/in²
- 1 µHg 0°C (32°F)
- 0.00000000863249 tsi (uk, long)
- 0.00000000966839 tsi (usa, short)
- 0.00000139225 tsf (usa, short)
- 0.00278450 psf
- 0.00135951 g/cm²

*Please note that the conversion factors above are accurate to 6 significant figures.*

**Low pressure measurement products**

- -10 to +10 inH2O Air Pressure Sensor for Ventilation & Extraction
- 100 Pa bi-directional range differential air pressure transmitter
- 30 ounces per square inch range pressure gauge with built-in logger
- -20 to 20 inH2O g compound range 0-10Vdc output air pressure sensor for oem use

## Derivation

The calculation below shows how the pressure unit microns of mercury (µHg) is derived from SI Units.

#### Formula

- Pressure = Force / Area
- Force = Mass x Acceleration
- Mass = Density x Volume
- Volume = Area x Height
- Acceleration = Distance / (Time x Time)

#### 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 µm = 0.000001 m
- Acceleration = Standard Gravity = 9.80665 m/s²

#### Calculation

- 1 µHg Mass = 13595.1 kg/m³ x 1 m² x 0.000001 m = 0.0135951 kg
- 1 µHg Force = 0.0135951 kg x 9.80665 m/s² = 0.1333223874 N
- 1 µHg Pressure = 0.1333223874 N / 1 m² = 0.1333223874 Pa

**Low pressure measurement products**

- PrimAtü 10 Low Cost Low Range Differential Air Pressure Transducer
- Low Differential Pressure Transmitters
- 1.5 inWG differential pressure transducer to control positive pressure inside a building
- 100 Pa bi-directional range differential air pressure transmitter

## Alternate Descriptions

These are the different versions used for identifying mmHg that you may find elsewhere.

- Micron of Mercury
- Microns of Mercury
- Micrometre of Mercury
- Micrometer of Mercury
- Micron of Mercury Column
- Microns of Mercury Column
- Micrometre of Mercury Column
- Micrometer of Mercury Column
- µHg
- µ Hg
- µmHg
- µm Hg
- micron Hg
- micronHg

**Low pressure measurement products**

- Digital sensor for leakage monitoring at 1 kilopascal on a PC
- 10 psig 4-20mA out submersible freshwater pressure sensor for underwater structure research
- XMD Process Plant DP Cell Differential Pressure Transmitter
- 0-50 mbarg 4-20 mA output natural gas monitoring pressure sensor

## Measurement Unit Related Terms

More pages related to measurement unit technical terms.

- at – Technical Atmosphere Pressure Unit
- atm – Standard Atmosphere Pressure Unit
- bar Pressure Unit
- cmH2O – Centimetres of Water Column at 4 deg C Pressure Unit
- cmHg – Centimetres of Mercury at 0 deg C Pressure Unit
- daPa – Dekapascal Pressure Unit
- dyn/cm² – Dyne per Square Centimetre Pressure Unit
- ftH2O – Feet of Water Column at 4 deg C Pressure Unit
- g – Acceleration due to Gravity
- g/cm² – Grams per Square Centimetre Pressure Unit
- hPa – Hectopascal Pressure Unit
- inH2O – Inches of Water Column at 4 deg C Pressure Unit
- inHg – Inches of Mercury at 0 degrees C Pressure Unit
- kg/cm² – Kilogram per Square Centimetre Pressure Unit
- kg/mm² – Kilogram per Square Millimetre Pressure Unit
- kPa – Kilopascal Pressure Unit
- ksi – Kilopounds per Square Inch Pressure Unit
- mbar – Millibar Pressure Unit
- mH2O – Metres of Water Gauge at 4 deg C Pressure Unit
- mmH2O – Millimetres of Water Column at 4 deg C Pressure Unit
- mmHg – Millimetres of Mercury at 0 deg C Pressure Unit
- MPa – Megapascal Pressure Unit
- mPa – Millipascal Pressure Unit
- mTorr – Millitorr Pressure Unit
- N/cm² – Newton per Square Centimetre Pressure Unit
- N/m2 – Newton per Square Metre Pressure Unit
- N/mm² – Newton per Square Millimetre Pressure Unit
- oz/in² – Ounce per Square Inch Pressure Unit
- Pa – Pascal Pressure Unit
- Pressure
- Pressure Units
- psf – Pounds per Square Foot Pressure Unit
- psi – Pounds per Square Inch Pressure Unit
- Specific Gravity
- Torr Pressure Unit
- tsf – Tons per Square Foot (USA, Short) Pressure Unit
- tsi – Tons per Square Inch (UK, Long) Pressure Unit
- tsi – Tons per Square Inch (USA, Short) Pressure Unit
- Water Density