Which two factors most impact the effectiveness of chlorination?

The effectiveness of chlorination is significantly influenced by the concentration of chlorine and the contact time. Concentration refers to the amount of chlorine present in the water, which directly affects its ability to disinfect and kill pathogens. Higher concentrations generally lead to more effective disinfection, as there are more active chlorine molecules available to react with and destroy microorganisms.

Contact time is equally important; it is the duration that chlorine remains in contact with the water. Effective disinfection requires adequate time for chlorine to interact with and inactivate pathogens. Insufficient contact time can result in incomplete disinfection, even if chlorine concentration is high; if the chlorine does not have enough time to react with the contaminants, it may not effectively reduce pathogen levels.

While factors like pH, temperature, and foreign substances can influence chlorination effectiveness, the primary determinants are the concentration of chlorine and the duration it is allowed to interact with the water. This makes the combination of these two factors critical for achieving optimal disinfection results.