What does a double check valve backflow assembly provide effective protection from?

A double check valve backflow assembly is specifically designed to prevent the backflow of contaminated water into the clean water supply. By having two independent check valves, it creates a robust barrier against potential pollutants or toxic substances that could enter the drinking water system due to pressure changes or other influences. The assembly is particularly useful in scenarios where there is a risk of cross-connection between potable water and sources that may contain hazardous materials.

This focus on protecting against pollution is crucial in maintaining the quality and safety of the water supply, ensuring that harmful substances do not compromise public health. The other options, while related to water system management, do not directly pertain to the primary function of the double check valve backflow assembly.