The airgap used in plumbing must be how many times the diameter of the pipe but not less than 1 inch?

The air gap in plumbing is an essential safety feature that prevents backflow, which can contaminate the potable water supply. The regulation stating that the air gap must be at least two times the diameter of the pipe, with a minimum distance of 1 inch, is based on established plumbing codes that promote adequate separation between wastewater and clean water sources. This distance helps ensure that in the event of a backflow incident, there is sufficient space to prevent any contaminants from entering the potable water system.

Having the air gap set at two times the diameter of the pipe strikes a balance between safety and practicality, minimizing the risk of potential health hazards while also considering space and installation feasibility in both residential and commercial plumbing systems. The regulation aims to establish a uniform standard that plumbers and builders can follow, contributing to the overall health and safety of water supply systems.