28. Hygrometer not to be affixed to wall, etc., unless protected by wood.
(1)No hygrometer shall be affixed to a wall, pillar or other surface unless protected therefrom by wood or other non-conducting,material at least half an inch in thickness and distant at least one inch from the bulb of each thermometer.(2)No hygrometer shall be affixed at a height of more than 5 feet 6 inches from the floor to the top of thermometer stem or in the direct draughts from a fan window, or ventilating opening.
