This standard provides conversion factors for units of measurement for a number of quantities, which are, or have been, in general use in engineering, industry and trade. The subjects covered are, broadly, metrology, mechanics and heat; the standard does not deal with purely electrical units.
NOTE 1 SI units are normally recommended. However, in certain circumstances use of particular units is required by legislation.
NOTE 2 Electrical and light units are given in BS 5775-5 and in BS 5775-6, respectively.
NOTE 3 A commentary on imperial and metric systems of measurement and units is given in Annex A.