1.1 This recommendation applies to the following two types of standard cells used as electromotive force (e.m.f.) references, viz.: — saturated standard cells; — unsaturated standard cells. 1.2 This recommendation does not apply to : — cells used as international or national standards of e.m.f.; — assemblies consisting of a temperature-controlled enclosure containing one or more standard cells; — sources of e.m.f. intended to supply a current.