What does CT stand for in water disinfection?

The correct answer is Contact Time, which is crucial in the context of water disinfection processes. CT is a product of the concentration of the disinfectant (like chlorine) and the time it is in contact with the water being treated. This parameter is essential because it determines the effectiveness of the disinfection process. The greater the concentration of the disinfectant and the duration of time that it is allowed to interact with pathogens in the water, the more effectively those pathogens can be inactivated.

In practical terms, when a water treatment facility monitors or adjusts the amount of disinfectant used or the duration of its application, they are manipulating the CT value to ensure adequate disinfection. Insufficient CT can result in incomplete pathogen removal, which poses a risk to public health. This concept underscores why understanding and optimizing contact time is vital for achieving safe drinking water standards.