The air gap between the faucet and sink overflow rim should be how many times the diameter of the supply pipe?

The correct answer reflects a crucial principle in plumbing and public health protection. An air gap is a physical separation between the end of a water supply pipe and the overflow rim of a receptacle, such as a sink. This design prevents any backflow of contaminated water into the potable water supply.

The requirement for the air gap is that it must be at least one and a half times the diameter of the supply pipe. This specification is based on ensuring that there is an adequate separation to protect against back siphonage or backflow, which can lead to contamination of drinking water with harmful pathogens and chemicals. The one and a half times ratio is a widely accepted standard that addresses the risk factors associated with pressure changes within the plumbing system.

Establishing this air gap not only complies with sanitation regulations but also enhances public health safety by preventing water contamination effectively. Understanding and implementing such standards is essential for environmental health specialists to maintain safe environmental conditions and ensure the safety of the water supply.