4715.1910 IDENTIFICATION OF POTABLE AND NONPOTABLE WATER.
In all buildings where dual water distribution systems, one potable water and other nonpotable water, are installed, each system shall be identified, either by color marking or metal tags.
When color marking is used, potable water lines should be painted green and nonpotable water lines should be painted yellow. This requirement may be met by painting three-inch-wide bands green or yellow at intervals of not more than 25 feet and at points where piping passes through walls, floors, or roofs in which case the bands shall be applied to the piping on both sides of the walls and both above and below the floor or roof. Points of outlets for nonpotable water shall be marked with a tag or color coded.
When tags are used, potable water lines shall be identified by three-inch-diameter metal tags bearing the legend "SAFE WATER" in letters not less than one-half inch in height.
Nonpotable water lines shall be identified by firmly attached metal tags having the shape of a four-inch equilateral triangle bearing the legend "NONPOTABLE WATER" in letters not less than 7/16 inch in height.
As in the use of color bands, tags shall be attached to pipes at intervals of not more than 25 feet, and, at either side of points where pipes pass through walls and above and below points where pipes pass through floors or roofs.