Covers screwed conduit of the type referred to as Class B, and flexible conduit. It specifies materials, construction and protective coatings, and lays down dimensions and tolerances. Three categories of protection have been allowed for: heavy (galvanized), medium (zinc-coated), and light (painted or varnished). It includes requirements for rigid conduit fittings and flexible conduit connectors. Tests cover dimension, earth continuity, marking, mechanical properties and protective coatings. The Standard is generally in line with IEC requirements.