If the natural fluoride content of raw water is variable, how often should it be measured?

• A. Weekly
• B. Once a month
• C. Every day
• D. Once a year

Answer: (C)

When the natural fluoride content of raw water is variable, it is crucial to measure it every day. Regular measurement is necessary because fluoride levels can fluctuate due to various factors, including changes in water sources, seasonal variations, and anthropogenic influences such as agricultural runoff or industrial discharges. Daily monitoring ensures that the water treatment facility can quickly adapt treatment processes to maintain water quality standards and comply with health regulations.

By measuring fluoride levels daily, operators can detect any significant changes in concentration, allowing for timely adjustments in treatment protocols. This approach helps to ensure that the water remains safe for consumption and meets public health guidelines. Regular daily measurements enhance the ability to respond to fluctuations and ensure consistent water quality, thus preventing potential health risks associated with excessive fluoride levels.