# Calculations

## Pressure Converter

Here, the pressures in different scales can be converted.

Just enter the value, unit and confirm using 'OK '.

Metric: | 1 | Pa | Pascal |

10⋅10^{-6} | bar | Bar | |

0.01 | hPa | Hectopascal (Millibar) | |

0.008 | Torr | Torr | |

10.197⋅10^{-6} | at | Technical atmosphere | |

9.869⋅10^{-6} | atm | Atmosphere | |

Anglo-American: | 145.037⋅10^{-6} | psi | Pound-force per square inch |

## Pressure:

**Metric system:** In SI system, the unit of pressure is the Pascal (Pa), named after the French physicist Blaise Pascal. One Pascal is defined as the pressure caused by a force of one Newton on an area of one square metre. Another common unit is the bar, which corresponds to 10000 Pa. The name is derived from the Greek word barys. In daily use, especially in describing the air-pressure, the unit hectopascal, equal to one millibar is used (1 hPa = 100 Pa = 1 mbar).

A unit that is frequently used in the USA today is the Torr, named after the Italian physicist Evangelista Torricelli. One Torr is defined as the 760th part of the atmosphere, which is approximately equal to the pressure, caused by millimetre of mercury. In daily life this unit is found mainly in blood pressure measurement.

A rarely used unit is the technical atmosphere (at = 98066.5 Pa), which is defined by the pressure in 10 m deep water.
In contrast to this, the physical atmosphere (atm = 101325 Pa) is defined by the average air pressure at sea level.

**Anglo-American system:** In Anglophone countries the unit 'pound-force per square inch' is used: (1 psi = 6894.757 Pa) One psi is the pressure exerted by the weight-force of one pound on an area of one square inch.