Florida Drinking Water Operator "B" Practice Test

True or False: Longer contact times are required to disinfect water at lower temperatures.

1. True

2. False

3. It depends on the disinfectant

4. None of the above

The correct answer is: True

The statement that longer contact times are required to disinfect water at lower temperatures is indeed true. Disinfection is a process that often relies on maintaining appropriate temperatures; as the water temperature decreases, the effectiveness of certain disinfectants, like chlorine and chloramine, can be reduced. This is due to the slower kinetics of the disinfection process at lower temperatures, which leads to a slower reaction rate between the disinfectant and microorganisms present in the water. As a result, achieving the same level of microbial inactivation requires extending the contact time between the disinfectant and the water. This ensures that the disinfectant has adequate time to penetrate and kill or inactivate the pathogens effectively. Understanding this principle is crucial for water operators to ensure the safety and quality of the drinking water supplied to the community, especially during colder seasons or in cooler climates. This concept is foundational for assessing operational procedures within water treatment facilities, emphasizing the need for adjustments in treatment methods based on water temperature to guarantee compliance with health regulations and standards.