What does a pressure regulating device typically do?

A pressure regulating device's primary role is to control water pressure within a plumbing system. In fire protection systems, such as standpipes, it is crucial to manage the pressure to ensure that fire hoses receive a consistent flow without excessive pressure, which could cause damage or make the equipment difficult to handle.

By keeping the pressure at a predetermined level, the device helps ensure that firefighters can operate the system more effectively and safely. In contrast, while restricting water flow might be a secondary effect of managing pressure, that is not the main function of a pressure regulating device. Preventing contamination involves different mechanisms such as backflow preventers, while maintaining water temperature relies on other systems entirely. Thus, the answer underscores the importance of pressure control in a fire protection context.