Chlorine Monitoring

When chlorine is added to the water system, codes require that systems monitor the amount of chlorine added and the levels of chlorine in the system. Common terms associated with monitoring chlorine levels are:

• Residual- Chlorine level after the initial reaction
• Dosage- Amount of chlorine per gallon or unit
• Chlorine Demand- Amount of chlorine needed to react
• Free Chlorine Residual- Amount of chlorine available after the demand
• Combined Chlorine Residual- Amount of chlorine used
• Total Chlorine Residual- Total of free and combined chlorine