Which type of irrigation assembly is required for chemicals?

The correct choice for irrigation assembly required for chemicals is the Reduced Pressure Prevention Assembly. This assembly is specifically designed to protect the potable water supply from contamination by chemicals or pollutants that may be present in the irrigation system.

The Reduced Pressure Prevention Assembly operates by maintaining a lower pressure in the drinking water supply compared to the water in the irrigation system. This pressure differential prevents any backflow of potentially contaminated water into the drinking water supply. It includes two shutoff valves, a pressure differential relief valve, and test cocks to ensure proper functioning and compliance with safety standards.

In contrast, other types of assemblies have different applications and may not provide the same level of protection. For example, a Spill-Resistant Vacuum Breaker is primarily used to prevent back-siphonage but does not adequately protect against back pressure conditions that could occur with chemical usage. An Atmospheric Vacuum Breaker is also designed to prevent back-siphonage, but it may not be suitable for situations involving chemicals due to its inability to handle back pressure effectively. The Double Check Valve Assembly is used for moderate risk backflow situations, but it does not provide the same level of assurance as the Reduced Pressure Prevention Assembly when it comes to preventing contamination from chemicals.

Therefore, the Reduced Pressure