What is the main purpose of installing a backflow prevention device in a sprinkler system?

The main purpose of installing a backflow prevention device in a sprinkler system is to prevent contaminated water from entering the main supply. This is crucial in protecting the public water system from potential hazards, particularly in scenarios where water may flow backward due to changes in pressure. If there is a drop in pressure in the main supply, water from the sprinkler system—potentially containing chemicals or contaminants—could flow back into the public water supply, leading to health risks for the community. Backflow prevention devices maintain the integrity of the water supply by ensuring that water flows in one direction only, thereby safeguarding drinking water quality and aligning with health and safety regulations.

While other options mention aspects related to water flow and system pressure, they do not address the critical function of protecting the potable water source, which is the essence of why backflow prevention devices are mandated in many building codes and plumbing standards.