SI unit of pressure and stress
(Redirected from HPa)
The pascal (symbol: Pa) is the SI derived unit of pressure or stress. It is a measure of perpendicular force per unit area i.e. equal to one newton per square meter. In everyday life, the pascal is maybe best known from meteorological air-pressure reports, where it happens in the form of hectopascal (1 hPa = 100 Pa). In other cases, the kilopascal is more commonly used, for example on bicycle tire labels. One hectopascal corresponds to 0.1 and one kilopascal to about 1% of atmospheric pressure (near sea level).
It is named after the French mathematician and physicist, Blaise Pascal.
- ↑ World Meteorological Organization: Manual on the Global Observing System – Volume I, Section 22.214.171.124: "The hectopascal (hPa), equal to 100 pascals (Pa), shall be the unit in which pressures are reported for meteorological purposes."
- ↑ ISO 5775: Bicycle tyres and rims