What is Total Chlorine?

Total chlorine is defined as the sum of free chlorine and combined chlorine. Free chlorine refers to the chlorine available in the water to disinfect and kill pathogens, while combined chlorine consists of chloramines, which are formed when chlorine reacts with nitrogenous compounds in the water, such as organic matter or ammonia.

Understanding total chlorine is important for water treatment operators because it provides a complete picture of the chlorine present in the water system and its effectiveness as a disinfectant. Monitoring total chlorine levels helps operators ensure that the water meets safety standards for public consumption and is adequately treated for pathogen control.

The other options do not accurately define total chlorine. The total chlorine dosage added to water does not account for what remains in the system after reactions have taken place. The chlorine remaining after treatment is not a comprehensive measure of all forms of chlorine present. Lastly, while the level of chlorine in treated wastewater can reflect chlorine presence, it does not address the definitions of free and combined chlorine crucial for defining total chlorine.