British Standard Specification (BS/ARP 20) for: Methods for Providing Even Illumination of Low Intensity (0.02 Foot-Candles)

This Specification has been prepared under the aegis of a Joint Committee of the Illuminating Engineering Society and the Home Office (A.R.P. Department), by a Sub-Committee of the Society. It forms one of a series of Specifications issued by the B.S.I. at the request of the Air Raid Precautions Department of the Home Office.