Barrer

Barrer is a non-SI unit of gas permeability (specifically, gas permeability) used in the membrane technology and contact lens industry. It is named after Richard Barrer.

${\displaystyle {\rm {{1}\ barrer={10^{-10}}{\frac {cm_{STP}^{3}\cdot cm}{cm^{2}\cdot s\cdot cmHg}}}}}$

Here the 'cm³_STP' is standard cubic centimeter, which is a unit of amount of gas rather than a unit of volume. It represents the amount of gas molecules or moles that would occupy one cubic centimeter at standard temperature and pressure, as calculated via the ideal gas law.

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