What is the maximum allowable cyanuric acid level in a spa?

The maximum allowable cyanuric acid level in a spa is 40 mg/L. This limit is set to ensure effective management of chlorine's stability in disinfecting the water while preventing potential issues associated with very high concentrations of cyanuric acid. Cyanuric acid acts as a stabilizer for chlorine, which helps in protecting it from degradation due to sunlight. However, excessive levels can lead to decreased chlorine effectiveness, making it harder to maintain proper disinfection levels.

Having a limit of 40 mg/L helps ensure that spas can effectively utilize chlorine without the negative effects of high cyanuric acid levels. This is important for maintaining water quality, protecting the health of bathers, and ensuring compliance with health safety regulations.