608.16.1 Protection by Air Gap
Openings and outlets shall be protected by an air gap between the opening and the fixture flood level rim as specified in Table 608.16.1. Openings and outlets equipped for hose connection shall be protected by means other than an air gap.
MINIMUM REQUIRED AIR GAPS
|FIXTURE||MINIMUM AIR GAP|
|Away from a walla (inches)||Close to a wall (inches)|
|Lavatories and other fixtures with effective openings not greater than 1/2 inch |
|Sinks, laundry trays, gooseneck back faucets and other fixtures with effective |
openings not greater than 3/4 inch in diameter
|Over-rim bath fillers and other fixtures with effective openings not greater |
than 1 inch in diameter
|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 circle7/16 inch in diameter)
|Effective openings greater than 1 inch||Two times the diameter of the||Three times the diameter of|
For SI: 1 inch = 25.4 mm, 1 square inch = 645 mm2.