How long should FAC remain above 50 PPM during super chlorination?

During super chlorination, maintaining a free available chlorine (FAC) level above 50 parts per million (PPM) is crucial for effectively disinfecting water and ensuring that harmful pathogens are eliminated. The recommended duration for keeping the FAC above 50 PPM is four hours. This extended period allows enough time for the chlorine to react with any contaminants, including bacteria, viruses, and organic matter in the water, maximizing the disinfection process.

A shorter duration may not adequately ensure that all contaminants are effectively killed off or inactivated, potentially leading to unsafe water conditions. Thus, keeping the FAC above the required threshold for four hours not only adheres to safety protocols but also ensures compliance with water treatment standards to protect public health.