What is the role of a pressure vacuum breaker in an irrigation system?

A pressure vacuum breaker plays a crucial role in maintaining the safety and integrity of an irrigation system by preventing back-siphonage into the potable water supply. Back-siphonage occurs when there’s a drop in water pressure that can draw water from the irrigation system back into the main water supply, potentially introducing contaminants into clean drinking water.

The vacuum breaker works by automatically opening to allow air into the system when the pressure drops, thus breaking the siphon effect and stopping any contaminated water from being drawn back. This functionality is essential for safeguarding public health and complying with plumbing codes, which mandate protection against cross-connections to avoid contamination of potable water.

In contrast, the other options relate to functions that are not within the scope of a pressure vacuum breaker's purpose. For instance, increasing water pressure or filtering contaminants does not align with the primary function of preventing back-siphonage. This illustrates the importance of understanding the specific roles of components within an irrigation system to ensure proper installation and compliance with safety standards.