Millimetre of mercury mmHg
About the Millimetre of mercury
The conventional millimetre of mercury is the pressure of a 1 mm column of mercury of standard density under standard gravity, defined as 133.322387415 pascals. It remains the standard unit for blood pressure worldwide, so a reading of 120/80 is in mmHg. It is almost identical to the torr.
Related Units
Standard atmosphere
atm101,325 Pa (exact)
The standard atmosphere is exactly 101,325 pascals, roughly average sea-level air pressure. It was historically the...
Torr
Torr101,325/760 Pa ≈ 133.322 Pa
The torr is exactly 1/760 of a standard atmosphere, about 133.322 pascals. It is named after Evangelista Torricelli...
Pascal
Pa1 Pa = 1 N/m² = 1 kg·m⁻¹·s⁻²
The pascal is a pressure of one newton per square metre, named after Blaise Pascal. It is a small unit: standard...
Bar
bar1 bar = 100,000 Pa (exact)
The bar equals 100 kilopascals, close to but slightly less than one standard atmosphere of 101,325 Pa. Its submultiple...