Electrical (other than electronic) devices, not covered by British Standards for single-phase a.c. or d.c. circuits, declared voltage between conductors 30 volts a.c. or 50 volts d.c. up to 250 volts. Materials, construction, finish, terminals, connection to electricity supply, cord grip, conductors, safety requirements (inaccessiblity of live parts, provision for earthing, test requirements). Joint and junction boxes, switch sockets, tests. See also BS 3676.