| 3717-1-05.1(D) Critical Observed the air gap between a plumbing fixture and a piece of equipment that was not sufficient to prevent back siphonage of contaminated water. Air gap insufficient at prep sink. To prevent contamination, an air gap between the water supply inlet and the flood level rim of the plumbing fixture, equipment, or nonfood equipment shall be at least twice the diameter of the water supply inlet and may not be less than one inch (25 millimeters).  |