3717-1-05.1(D) / Backflow prevention - air gap.
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. OBSERVED: Drain line from Ultra force hot water heater in sewage line which creates a cross connection which could contaminate the water supply & cause a foodborne illness. Remove cross connection.
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). Correct By: 16-Oct-2017