What is the maximum residual disinfectant limit for chloramine?

The maximum residual disinfectant limit for chloramine is established to ensure safe drinking water while effectively controlling pathogens. In North Carolina, and in accordance with the Environmental Protection Agency (EPA) guidelines, the limit is set at 4 ppm for total chlorine, which encompasses chloramines as a form of disinfectant. However, specifically for chloramine, the limit is 3 ppm, which aligns with the understanding of chloramine as a regulated disinfectant by states following federal standards.

This limit is significant because chloramines, which are formed by combining chlorine with ammonia, are used in water treatment as a secondary disinfectant. They are less volatile than chlorine and are effective at preventing the regrowth of bacteria in the distribution system. Ensuring that levels do not exceed the established limit protects public health while maintaining the efficacy of water treatment processes.