Air and Water Pollution Control (AWPC) Exam 1 Practice

UV disinfection uses ultraviolet light (UV-C) to inactivate microorganisms by damaging their genetic material. It’s very effective against a wide range of pathogens when the water is clear, but turbidity and colored substances in water absorb and scatter UV light, causing shielding of organisms and a loss of disinfection effectiveness. Because the system runs on electrical power to operate the lamps and maintain the dose, it inherently requires energy. Unlike chemical methods, UV leaves no residual disinfectant in the water, which is another practical consideration. So UV fits as the option that is effective yet sensitive to turbidity and energy-dependent.