Pascal (unit)

The pascal (symbol: Pa) is the SI derived unit of pressure used to quantify internal pressure, stress, Young's modulus, and ultimate tensile strength. The unit, named after Blaise Pascal, is defined as one newton per square metre[1] and is equivalent to 10 barye (Ba) in the CGS system. The unit of measurement called standard atmosphere (atm) is defined as 101,325 Pa.[2]

pascal
A pressure gauge reading in psi (red scale) and kPa (black scale)
General information
Unit systemSI unit
Unit ofPressure or stress
SymbolPa
Named afterBlaise Pascal
Derivation1 Pa = 1 N/m2
Conversions
1 Pa in ...... is equal to ...
   SI base units:   kgm−1s−2
   US customary units:   1.45038×10−4 psi
   atmosphere:   9.86923×10−6 atm
   bar:   10−5 bar
   barye (CGS unit)   10 Ba

Common multiple units of the pascal are the hectopascal (1 hPa = 100 Pa), which is equal to one millibar, and the kilopascal (1 kPa = 1000 Pa), which is equal to one centibar. Meteorological observations typically report atmospheric pressure in hectopascals per the recommendation of the World Meteorological Organization. Reports in the United States typically use inches of mercury[3] or millibars,[4][5] in Canada these reports are given in kilopascals.[6]