Single capillary systems can be used to provide gas mixtures where the minor component is in the range of volume fractions from 10-8 to 0,5.
The relative expanded uncertainty of this technique is less than ±2 % (k = 2) relative. This application is used in industrial gas mixing panels for the production of specific gas atmospheres.
Gas dividers can be used to divide gas mixtures prepared from gases or gas mixtures into controlled proportions by volume. These devices are capable of dilutions in the range of volume fractions from 0,000 5 to 0,9 of the primary gas concentration with a relative repeatability of better than 0,5 %.
Traceability of the gas mixtures produced by a gas divider is achieved by comparison of a mixture with gas mixtures related to national or international gas standards. An example is given in Annex A.