Are there different types of backflow prevention devices?

There are two types of backflow prevention devices for premise isolation:

Reduced Pressure Pricipal Assembly (RP) devices - these are used for any type of cross-connection or potential cross-connection involving water that has additives or substances, that, under any concentration, can create a danger to health.

Double Check Valve Assembly (DCVA) devices - used on connections that have a low probability of becoming a high or severe hazard.