(1) Every owner of a building which contains a stairway or passage designed to be used by more than one tenant shall install and maintain a lighting system capable of producing illumination at any one point of not less than 50 lux on all such stairways or passages

(2) Lights on landings and on other parts of such a stairway and in a passage shall be kept on through-out the hours of darkness, or a any time when the illumination would otherwise fall below 50 lux, or switches shall be provided and so arranged that the light may be switched on above or below each flight of stairs or at either end of the passage.

(3) Where passageways and stairways are only artificially lit they shall be provided with emergency lighting of not less than 20lux at floor level.