Which device is specifically designed to prevent back siphonage under continuous pressure?

The anti-siphon vacuum breaker (pressure type) is specifically designed to prevent back siphonage under conditions of continuous pressure. This device operates by creating an air gap that allows atmospheric pressure to interrupt any potential siphon action. It is crucial in situations where the potable water supply might be exposed to contaminants, as it effectively stops any backflow that could lead to contamination.

In contrast, a check valve primarily allows fluid to flow in one direction but does not create the necessary air gap to troubleshoot issues caused by back siphonage. It is typically used to prevent reverse flow but may not prevent back siphonage effectively if there is a drop in the water supply pressure.

A pressure relief valve is designed to relieve excess pressure in a system to prevent over-pressurization, and while it serves an important function in maintaining system integrity, it does not prevent back siphonage.

Similarly, a backwater valve is used to prevent flooding by stopping backflow from the sewer system into a building, but it does not address the issue of back siphonage related to potable water. Each of these other devices addresses different aspects of plumbing safety and functionality but does not specifically target back siphonage prevention in a continuous pressure scenario like the anti-siph