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inHg - Inches of Mercury at 0 degrees C Pressure Unit
Inch of Mercury is a British and American unit of measure for pressure. 1 inch of Mercury at 0 degrees Celsius (32 deg F) equals 3386.39 Pascals. An inch of mercury at zero degrees Celsius is defined as the pressure exerted by a column of mercury with a density of 13,595.1 kg/m3 under the pull of gravity at 9.80665 m/s2.
The inHg pressure unit is not used so extensively in the UK anymore and has been mostly replaced by the metric units mmHg and mbar. However, inches of Mercury are still used extensively in the USA particularly for meteorological purposes when measuring atmospheric pressure.
Mercury has a very high density which made it a very practical liquid for use inside fluid filled columns for measuring pressure in the laboratory. However Mercury is now considered a hazardous substance and mercury manometers have been almost totally eliminated from laboratories for health and safety reasons.
Use the following conversion factors to convert from inHg to other pressure units or vice versa. To convert a reading in inHg to another unit multiply it by the relevant pressure conversion factor. To convert a reading in any pressure unit to inHg divide it by the relevant pressure conversion factor.
Alternatively convert from a inHg pressure value into another unit using the pressure unit converter.
Read how inHg is derived from SI units or verify a pressure unit is one of the various forms used for inHg.
| 0.0338639 | bar |
| 0.491154 | psi |
| 33.8639 | mbar |
| 3386.39 | N/m² |
| 3386.39 | Pa |
| 33.8639 | hPa |
| 3.38639 | kPa |
| 0.00338639 | MPa |
| 0.0345315 | kg/cm² |
| 345.315 | mmH2O 4°C (39.2°F) |
| 34.5315 | cmH2O 4°C (39.2°F) |
| 0.345315 | mH2O 4°C (39.2°F) |
| 13.5951 | inH2O 4°C (39.2°F) |
| 1.13292 | ftH2O 4°C (39.2°F) |
| 25.4000 | mmHg 0°C (32°F) |
| 2.54000 | cmHg 0°C (32°F) |
| 1 | inHg 0°C (32°F) |
| 25.4000 | Torr |
| 25400 | mTorr |
| 0.0334211 | atm |
| 0.0345315 | at |
| 33863.9 | dyn/cm² |
| 7.85847 | oz/in² |
| 25400.0 | µHg 0°C (32°F) |
| 0.000219265 | tsi (uk, long) |
| 0.000245577 | tsi (usa, short) |
| 0.0353631 | tsf (usa, short) |
| 70.7262 | psf |
| 34.5315 | 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 in = 0.0254 m
Acceleration = Standard Gravity = 9.80665 m/s²
Calculation
1 inHg Mass = 13595.1 kg/m³ x 1 m² x 0.0254 m = 345.31554 kg
1 inHg Force = 345.31554 kg x 9.80665 m/s² = 3386.38864 N
1 inHg Pressure = 3386.38864 N / 1 m² = 3386.38864 Pa
These are the different versions used for identifying inHg that you may find elsewhere.
Inches of Mercury
Inch of Mercury
Inches of Mercury Column
Inch of Mercury Column
inHg
in Hg
"Hg
" Hg
Site Last Updated: 07/02/12
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