What type of plumbing device can help stop backflow?

An Atmospheric Vacuum Breaker (AVB) is designed specifically to prevent backflow in plumbing systems, which is a critical measure for maintaining safe water quality. When water pressure drops in a system, there is a risk that contaminants can enter the clean water supply through backflow. The AVB functions by breaking the vacuum that could otherwise draw water back into the supply line, ensuring that the flow of water only goes in the intended direction.

In contrast, other devices mentioned do not serve the same purpose. A sediment trap is used to collect solids and prevent them from clogging drainage systems. A pressure relief valve is designed to release pressure in a system to prevent damage, and while it plays an important role in safety, it does not prevent backflow. A water meter measures the flow of water but does not prevent contaminants from re-entering the water supply. Thus, the AVB is the correct choice for effectively stopping backflow.