For which duration must the chlorine concentration be maintained after a fecal incident involving solid stools?

After a fecal incident involving solid stools, the chlorine concentration must be maintained at the recommended level for 25 minutes to effectively disinfect the water. This duration ensures that the chlorine can adequately inactivate pathogens that may be present in the feces.

Solid fecal matter can harbor a variety of harmful pathogens, including bacteria and viruses, which can pose serious health risks to swimmers if not properly managed. The 25-minute contact time at the specified chlorine concentration is based on guidelines that provide sufficient time for the chlorine to react with and eliminate these pathogens.

Chlorine levels must be adjusted to a higher concentration, typically around 2-5 parts per million (ppm), during this period to enhance the efficacy of disinfection. Maintaining this level for the full 25 minutes allows the chlorine to penetrate and neutralize microorganisms effectively, thereby helping to ensure the safety of the swimming environment post-incident.