Which backflow preventor type is described for the pedicure chair hazard?

• A. Reduced pressure principle
• B. Double check valve
• C. Atmospheric vacuum breaker
• D. Any of the above

Answer: (A)

The main idea here is choosing a backflow prevention device that can protect drinking water from a cross-connection created by a pedicure chair, where chemicals and contaminated water can be drawn back into the supply if pressure changes occur. In a pedicure chair setup, you want a device that guards against both backsiphonage and backpressure, because either condition could pull hazardous substances into the potable supply.

The best choice is the reduced pressure principle backflow preventer. It contains two check valves and a pressure-relief valve that vents to atmosphere if downstream pressure rises above upstream pressure. That configuration provides the highest level of protection for high-hazard cross-connections, such as those involving chemical disinfectants or wastewater in a pedicure chair, and it remains effective even when system pressures fluctuate. It’s typically required by code for installations where there’s a real risk of contamination.

A double check valve offers protection, but it’s considered less protective for high-hazard cross-connections and may not be sufficient for situations with potential chemical backflow. An atmospheric vacuum breaker protects against backsiphonage only and cannot handle backpressure; it also has installation limitations and can fail if vents clog or if there’s continuous pressure on the supply. Therefore, for the pedicure chair hazard, the reduced pressure principle device is the appropriate, most protective choice.