An air gap and a reduced pressure principle assembly (RP) are both acceptable for high-hazard protection. What is one key advantage of an air gap over an RP assembly?

Giải thích

An air gap is a fixed physical separation with no moving parts, so it cannot mechanically fail or foul the way an RP can, which is its key reliability advantage. However, an air gap breaks pressure entirely, so it cannot maintain downstream pressure or function as a pressurized in-line device, and it is the RP, not the air gap, that requires periodic testing.