Water Distribution Grade 1 Certification Practice Exam

Which statement is true about a double check valve backflow assembly?

1. It is designed to stop backsiphonage of all hazards

2. It protects against low hazardous backflow

3. A double check valve is not designed to stop backsiphonage of a health hazard

4. It automatically self-tests for faults

The correct answer is: A double check valve is not designed to stop backsiphonage of a health hazard

The concept of a double check valve backflow assembly is crucial in understanding its purpose and functionality in water distribution systems. This assembly is specifically designed to prevent the backflow of water into the supply line, but it has limitations based on the type of hazards it can manage. The statement that a double check valve is not designed to stop backsiphonage of a health hazard accurately reflects its intended use. Double check valve assemblies are effective for preventing backflow resulting from low-hazard situations, such as those typically found in commercial or residential applications where non-potable water may enter the potable water system. However, in instances involving potential health hazards, such as chemicals or biological contaminants, a double check valve does not provide adequate protection. This is because it lacks the features needed to handle high-risk situations effectively, which are instead managed by assemblies like Reduced Pressure Zone (RPZ) devices that are meant for high-hazard circumstances. Therefore, the correct choice regarding the capabilities of a double check valve assembly is that it is indeed not equipped to prevent backsiphonage of health hazards, emphasizing the importance of using the appropriate backflow prevention device based on the risk level associated with the specific application.