Daytime Lighting of Blacked-out Factories

Abstract

THE Industrial Health Research Board is at present investigating the effects of complete obscuration of daylight on health and output, and also the problem of securing the best artificial lighting during the hours of daylight. R. Maxted and J. Bertram, who have been associated with this work, have written an interesting account in the Electrical Times of June 6 of experiments in factory lighting, reproducing by artificial means the most desirable features of natural lighting. Normal modern practice, based on pre-War experience, dwells on the importance of adequate illumination levels and of limitation of glare. But war-time conditions have greatly accentuated defects which were tolerable under peace conditions of working. In addition, the blacking-out of windows and skylights has usually resulted in conditions such that the psychological effect is of a magnitude creating an entirely new factor. It is unavoidable that operatives are required to work longer hours. It is obviously vital to ensure that any sense of strain is not associated in their minds with factory conditions, which should clearly be designed to conserve both mental and physical reserves. No other factor is more potent psychologically than the lighting installation. Diagrams are given showing the objectionable tunnel effect produced when the natural skylights are blacked out. The absence of distracting dazzle and the avoidance of glare raise and maintain the output of the factories.