During heavy use, what is the recommended concentration of free available chlorine for spas and hot tubs?

The recommended concentration of free available chlorine for spas and hot tubs during heavy use is 3.0-5.0 ppm. This range is important to ensure effective disinfection and oxidation of contaminants that are more prevalent when multiple users are in the water.

Heavy use can lead to an increased introduction of organic material, such as sweat, hair, and other body oils, as well as potential waterborne pathogens. Maintaining a chlorine level in this range helps to manage these challenges effectively by ensuring that chlorine is adequately available to sanitize the water, preventing any potential outbreaks of illness and ensuring a safe bathing environment.

Furthermore, higher chlorine levels are beneficial in offsetting the chemical demands brought on by bather load, allowing the sanitizer to remain effective throughout the day. Thus, keeping the free available chlorine in this specific concentration range is vital for protecting the health and safety of spa users.