What must be done to ensure a proper indication of water quality during sample testing?

What must be done to ensure a proper indication of water quality during sample testing?

• A. Change the sample bottles regularly
• B. Use distilled water for dilution
• C. Use treated bottles to dechlorinate the sample
• D. Test samples immediately after collection

Answer: (C)

To ensure a proper indication of water quality during sample testing, using treated bottles to dechlorinate the sample is important. Chlorine is a common disinfectant used in municipal water systems and can significantly affect the accuracy of certain water quality tests, particularly those measuring microbial life. If chlorine is present in the sample, it could inhibit the growth of microorganisms that are to be tested, leading to false negatives or inconclusive results. Therefore, treating the sample bottles to remove chlorine helps ensure that the test results accurately reflect the actual water quality. Other methods mentioned, while they may seem reasonable, do not directly address the concerns of chlorine interference. Regularly changing sample bottles may help prevent contamination, but it does not specifically deal with chlorine dechlorination. Using distilled water for dilution is relevant for maintaining water quality, but does not address the specific issue of chlorine in the sample. Testing samples immediately after collection is crucial for obtaining fresh data, but does not resolve any pre-existing chlorine problems that might already affect the sample before testing.

To ensure a proper indication of water quality during sample testing, using treated bottles to dechlorinate the sample is important. Chlorine is a common disinfectant used in municipal water systems and can significantly affect the accuracy of certain water quality tests, particularly those measuring microbial life. If chlorine is present in the sample, it could inhibit the growth of microorganisms that are to be tested, leading to false negatives or inconclusive results. Therefore, treating the sample bottles to remove chlorine helps ensure that the test results accurately reflect the actual water quality.

Other methods mentioned, while they may seem reasonable, do not directly address the concerns of chlorine interference. Regularly changing sample bottles may help prevent contamination, but it does not specifically deal with chlorine dechlorination. Using distilled water for dilution is relevant for maintaining water quality, but does not address the specific issue of chlorine in the sample. Testing samples immediately after collection is crucial for obtaining fresh data, but does not resolve any pre-existing chlorine problems that might already affect the sample before testing.