What is the name of the backflow preventor required for the pedicure chair hazard?

• A. Atmospheric vacuum breaker
• B. Double check valve
• C. Reduced pressure principle backflow preventor
• D. Check valve

Answer: (C)

The main idea is preventing contamination of the potable water supply when there’s a high-hazard cross-connection, like a pedicure spa where used water and disinfectants could backflow into the clean water line. A reduced pressure principle backflow preventor provides the strongest protection for these situations. It uses two check valves plus a relief valve that vents to atmosphere if pressure on the supply side drops, creating a low-pressure zone that stops any backflow from the spa or its chemicals from reaching the drinking water. This combination protects against both backpressure and back-siphonage, which is essential for health-sensitive installations like pedicure chairs.

Atmospheric vacuum breakers aren’t reliable under continuous pressure and can’t protect against backflow when the supply is pressurized, so they’re not appropriate for this hazard. A double check valve offers some protection but is not considered sufficient for high-hazard cross-connections found in spa equipment. A single check valve alone can be bypassed or overwhelmed and doesn’t provide the required safeguard against backflow in this context.