scope:

This International Standard specifies a method for the laboratory determination, using a glass hydrometer, of the density or relative density of crude petroleum products of mixtures of petroleum and non-petroleum products normally handled as liquids, and having a Reid vapour pressure of 1,8 bar (180kPa) or less, determined according to ISO 3007. Hydrometer readings are obtained at convenient temperatures, readings of density being reduced to 15 ° C or 20 ° C, and readings or relative density to 60 ° F, by means of international standard measurement tables. By means of these same tables, values determined in each of the two systems of measurement are convertible to equivalent values in the other, so that measurements may be made in the units of local convenience. The hydrometer method is most suitable for determinating the density of relative density of mobile transparent liquids. It can also be used for viscous oils by allowing sufficient time for the hydrometer to reach equilibrium or for opaque oils by employing a suitable meniscus correction.