What is an example of a potential backpressure plumbing connection?

A process water line is an example of a potential backpressure plumbing connection because it often involves the use of water that is pressurized for specific industrial or mechanical applications. In situations where pressure is generated, such as in a process water line that connects to equipment or systems that utilize pumps, there is a risk of backpressure being created. This can lead to the contamination of potable water sources if there is a cross-connection through which the backpressure can force non-potable water back into the public supply.

In contrast, other options present less risk of creating backpressure conditions. For instance, while a water heater line can potentially have pressure, it is typically designed with safety measures to prevent backflow events. A drainage system generally does not create backpressure; instead, it relies on gravity to transport wastewater away. Similarly, a shower supply line primarily delivers water under normal household pressure without adding significant risks associated with backpressure conditions. Thus, the process water line stands out as a clear example where backpressure could indeed be a concern.