What is combined chlorine defined as?

Combined chlorine is defined as the amount of chlorine present in the water that has reacted with organic matter and other substances, resulting in chloramines. It is critical for pool water quality management and sanitation. The measurement of total chlorine includes both free chlorine, which is the chlorine available to disinfect and kill pathogens, and combined chlorine, which is already bound with impurities.

Understanding this distinction is essential in pool maintenance; while free chlorine is effective for sanitization, combined chlorine can indicate that the chlorine is being utilized up from contaminants, leading to reduced effectiveness in maintaining water quality. Therefore, recognizing combined chlorine as the component that is included in the total chlorine measurement reinforces why it is defined in relation to both total and free chlorine values. This understanding is integral for pool operators in managing chemical balances to ensure swimmer safety and comfort.