Wastewater Operator Level 1 Practice Test

Access More Questions

If you double the contact time while keeping chlorine concentration constant, what happens to CT and disinfection effectiveness?

CT doubles; disinfection effectiveness decreases CT doubles; disinfection effectiveness remains the same CT doubles; disinfection effectiveness increases CT increases; disinfection effectiveness decreases

Correct Answer:

CT doubles; disinfection effectiveness increases

Explanation:

Disinfection dose is the product CT, where C is chlorine concentration and T is contact time. If you keep chlorine concentration the same and double the contact time, CT becomes twice as large. A higher CT delivers more disinfection dose to microorganisms, so disinfection effectiveness increases (within practical limits of the system and chemistry).

Access more questions from this quiz

Continue to Wastewater Operator Level 1 Practice Test for more practice questions and the full quiz experience.

Access More Questions