On an approved pressure vacuum breaker assembly, where are the shut off valves located?

The placement of shutoff valves in an approved pressure vacuum breaker assembly serves crucial operational and maintenance functions. Having shutoff valves at both the inlet and outlet of all assemblies allows for effective isolation of the assembly during testing or repair without disrupting the entire water supply system. This design feature is essential for ensuring that the backflow prevention mechanism can be maintained or replaced while minimizing service interruptions.

Including shutoff valves at both locations also helps maintain pressure and prevents contamination from entering the potable water supply during maintenance activities, which aligns with backflow prevention regulations and best practices in cross-connection control. The presence of these valves ensures that the assembly can be tested appropriately, which is a core aspect of ensuring compliance with safety standards.

Other options do not provide a comprehensive solution for operational flexibility and safety, as they limit the ability to isolate the assembly effectively for maintenance or repairs. This understanding reinforces the importance of proper installation and adherence to codes concerning backflow prevention systems.