608.15.1 Protection by air gap.
PC § 608.15.1
Openings and outlets shall be protected by an air gap between the opening and the fixture flood level rim as specified in Table 608.15.1. Openings and outlets equipped for hose connection shall be protected by means other than an air gap. Table 608.15.1Minimum Required Air Gaps FixtureMinimum Air GapAway from a Wall a(inches)Close to a Wall(inches)Lavatories and other fixtures with effective openings not greater than 1/2 inch in diameter1 1 1/2 Sinks, laundry trays, gooseneck back faucets and other fixtures with effective openings not greater than 3/4 inch in diameter1 1/2 2 1/2 Over-rim bath fillers and other fixtures with effective openings not greater than 1 inch in diameter2 3 Drinking water fountains, single orifice not greater than 7/16 inch in diameter or multiple orifices with a total area of 0.150 square inch (area of circle 7/16 inch in diameter)1 1 1/2 Effective openings greater than 1 inchTwo times the diameter of the effective opening Three times the diameter of the effective opening For SI: 1 inch = 25.4 mm, 1 square inch = 645 mm2. a. Applicable where walls or obstructions are spaced from the nearest inside-edge of the spout opening a distance greater than three times the diameter of the effective opening for a single wall, or a distance greater than four times the diameter of the effective opening for two intersecting walls.
