What is the maximum level of free chlorine permitted in a pool?

The maximum level of free chlorine permitted in a pool is typically set at 10 parts per million (ppm). This level is considered safe for swimmers while still effectively disinfecting the water and preventing the growth of harmful microorganisms. Chlorine plays a crucial role in maintaining water quality; however, excessive levels can lead to skin and eye irritation for swimmers, as well as impact the water's chemical balance.

Regulatory agencies and guidelines, such as those set by the Centers for Disease Control and Prevention (CDC) and the Environmental Protection Agency (EPA), recommend keeping free chlorine levels within this range to ensure both safety and public health. Keeping the free chlorine below or around this threshold allows for effective sanitation without adverse effects on users.