What does "pressure differential" signify in backflow prevention?

Pressure differential in the context of backflow prevention is crucial because it refers to the difference in pressure between the potable (drinking water) system and the non-potable (wastewater or other contaminated sources) system. This difference is significant because it helps to establish a protective barrier against potential backflow, which occurs when water flows in the opposite direction due to pressure changes.

When the pressure in the non-potable system is higher than that of the potable system, there is a risk that contaminated water could enter the safe drinking water supply. Thus, backflow prevention devices are designed to maintain a lower pressure in the potable water system to prevent any unwanted backflow of hazardous substances.

Understanding this pressure differential is vital for maintaining water safety and compliance with health regulations, ensuring that drinking water remains uncontaminated.