scope:

Covers low- and medium-voltage signs (excluding exit signs for cinemas, etc.) irrespective of the lamp employed, and high-voltage luminous-discharge-tube installations for external or internal use on circuits up to and including 5 kV to earth. Not lamps and auxiliaries operating below high voltage. Construction (wood and metal letters, emblems or devices, backing, glass panels, drainage, ventilation), electrical apparatus (transformers , inductors, resistors, flashers, capacitors), wiring, and construc tion and testing of cables. Suppression devices for radio interference caused by flasher signs, and testing for non-flammability are appended.