The compositions of gas mixtures are expressed in a number of different ways. These can change depending upon the mixture’s method of manufacture, the type of components within the mixture, the amount of each component, the process/analytical requirements, or simply the customer’s preference.
In each case the units of measure and the ratio of these units relative to each other are listed on the certificate provided by the manufacturer.
Gas mixtures are commonly certified using the following units of measure:
- mol Moles
- vol Volume
- mg/g/kg Miligrams/grams/kilograms