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Lighting in submarines.

Since the Second World War, the standard night-time illumination in RN submarine control rooms and adjacent spaces has been red lighting, because of its perceived advantage in dark adaption. Red light is, however, unpopular and has been shown to be detrimental to the performance of other control room tasks. In recent years evidence has emerged from the United States and other Navies that the advantage of red lighting over white lighting in terms of dark adaptation is insignificant at very low intensities. In this paper the research literature is reviewed and the findings related to current lighting practice in RN submarines. At the low levels of control room night illumination, there is minimal practical difference in the time taken for the periscope operator to dark adapt between red and white lighting. In view of the benefits to morale and performance offered by low level white lighting, it should replace red lighting for night use in submarine control rooms.