875—93.6 (89) Water gages.
	 93.6(1) Miniature power boilers for operation with a definite water level shall be equipped with a glass water gage for determining the water level. The lowest permissible water level for vertical boilers shall be at a point one-third of the height of the shell above the bottom head or tube sheet. When the boiler is equipped with an internal furnace, the water level shall not be less than one-third of the length of the tubes above the top of the furnace tube sheet. In the case of small boilers operated in a closed system where there is insufficient space for the usual glass water gage, water level indicators of the glass bull’s eye type may be used.
	 93.6(2) Miniature power boilers shall have the lowest visible part of the water gage glass located at least 1 inch above the lowest permissible water level specified by the manufacturer.
[ARC 8283B, IAB 11/18/09, effective 1/1/10]