Cross Connection Practice Exam

According to CAWWA guidelines, what is the minimum installation height for a Reduced Pressure Principle backflow preventer measured to the floor?

1. 600 mm (24)

2. 750 mm (30)

3. 900 mm (36)

4. 1,200 mm (48)

The correct answer is: 750 mm (30)

The minimum installation height for a Reduced Pressure Principle backflow preventer, as outlined by the California Association of Water Agencies (CAWWA) guidelines, is indeed 750 mm (30 inches) above the floor. This specific height is established to ensure that the backflow preventer functions effectively while maintaining accessibility for maintenance and inspection purposes. The regulated height reduces the risk of contaminants entering the potable water supply, as backflow preventers operate on the principle of creating a physical barrier to backflow, which could occur if there were a drop in system pressure. Elevating the device above a certain height helps alleviate potential risks associated with flooding or submersion that could compromise its function. Installing the backflow preventer at this minimum height also provides a sufficient air gap at the point of connection to mitigate any back-siphonage scenarios. By adhering to the recommended height, water system operators can confidently ensure the safety of the drinking water supply from possible pollutants.