Backflow Prevention Practice Exam

A hose-bibb connection is required to have a permanently installed ____?

1. Atmospheric vacuum breaker

2. Backflow preventer

3. Pressure vacuum breaker

4. Shut-off valve

The correct answer is: Atmospheric vacuum breaker

A hose-bibb connection requires a permanently installed atmospheric vacuum breaker to prevent backflow. This device is designed to protect the drinking water supply from contamination due to siphoning, which can occur when there is a sudden drop in water pressure. In scenarios where a hose is connected to a water supply, if the water in the hose is inadvertently siphoned back into the plumbing system—perhaps due to a break in the line or a sudden drop in pressure—the vacuum breaker allows air to enter the system, thereby interrupting the siphon effect and preventing any potentially contaminated water from flowing back into the potable water supply. While other options may seem appealing in certain contexts, they do not specifically meet the requirement for a hose-bibb connection. A backflow preventer can refer to various types of devices, but typically a hose-bibb does not require a type that may be more complex or appropriate in other settings. A pressure vacuum breaker is useful in different situations involving irrigation systems or certain plumbing setups, but not all hose bibb connections necessitate it. Lastly, a shut-off valve, while an important component for controlling flow, does not serve the primary function of preventing backflow. Hence, the atmospheric vacuum breaker is the most appropriate choice for ensuring safety at hose