Cross Connection Practice Exam

What is the primary purpose of an Atmospheric Vacuum Breaker in plumbing systems?

1. To maintain water pressure

2. To prevent back siphonage

3. To regulate water temperature

4. To control water flow rate

The correct answer is: To prevent back siphonage

The primary purpose of an Atmospheric Vacuum Breaker is to prevent back siphonage in plumbing systems. Back siphonage occurs when there is a drop in water pressure within the system, which can cause contaminated water to be drawn back into the clean water supply. The Atmospheric Vacuum Breaker functions by allowing air to enter the system when a negative pressure is created, closing off the potential pathway for contamination. This mechanism ensures that the potable water supply remains protected, effectively preventing any harmful substances from entering the drinking water system due to negative pressure situations. Other choices revolve around aspects that do not directly relate to back siphonage. Maintaining water pressure is essential for the function of plumbing but does not address the specific issue of preventing contamination through back siphonage. Regulating water temperature and controlling the water flow rate also serve different plumbing functions that are not the primary focus of an Atmospheric Vacuum Breaker.