BS 559:1955

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.