R 408.10681 Artificial lighting.

Rule 681. (1) A means of egress shall be illuminated by artificial lighting at places and for periods of time required to maintain the illumination to values not less than 1.0 footcandles measured at the floor. Illumination shall be so arranged that the failure of any single lighting unit, such as the burning out of an electric bulb, will not leave the area in darkness. (2) Artificial lighting shall be from a source of reasonable reliability, such as a public utility service. A battery operated electric light or any type of portable lamp or lantern shall not be used for primary exit illumination. Luminescent, fluorescent, or reflective material shall not be used as a substitute for required illumination.