Which scenario triggers backflow protection for a pedicure chair?

Which scenario triggers backflow protection for a pedicure chair?

• A. Water inlet below flush level rim
• B. Water inlet above flush level rim
• C. Pedicure chair water inlet with no spray hose
• D. Exterior faucet

Answer: (A)

Backflow protection is triggered when the pedicure chair’s water inlet sits below the flush level rim. If the inlet is lower than that rim, a drop in supply pressure or a surge can pull water from the chair back into the potable supply through the inlet, creating a backflow pathway. The height relative to the rim is what governs the risk, so when the inlet is below the rim, a backflow-prevention device or an air gap is needed to stop reverse flow. If the inlet is above the rim, siphoning back into the supply isn’t practically possible under normal conditions, so backflow protection isn’t required for that configuration. The presence or absence of a spray hose or an exterior faucet doesn’t change this fundamental height-related risk.

Backflow protection is triggered when the pedicure chair’s water inlet sits below the flush level rim. If the inlet is lower than that rim, a drop in supply pressure or a surge can pull water from the chair back into the potable supply through the inlet, creating a backflow pathway. The height relative to the rim is what governs the risk, so when the inlet is below the rim, a backflow-prevention device or an air gap is needed to stop reverse flow. If the inlet is above the rim, siphoning back into the supply isn’t practically possible under normal conditions, so backflow protection isn’t required for that configuration. The presence or absence of a spray hose or an exterior faucet doesn’t change this fundamental height-related risk.