GWWI Water Lab Analyst Practice Exam 2025 – Comprehensive All-in-One Guide to Success!

Accurate bacterial testing in water is influenced by multiple factors, and both temperature of the water sample and pH levels play significant roles.

Temperature is critical because it affects the metabolism and growth rates of bacteria. If the water sample is too cold, it may hinder bacterial growth to the point where the test yields false negatives, as the bacteria might not multiply adequately within the incubation period. Conversely, excessively high temperatures can kill bacteria or alter their behavior, also leading to inaccurate results.

pH levels are equally important, as they can directly impact bacterial survival and growth. Different bacterial species thrive within specific pH ranges, and if the pH of the sample is outside of the preferred range, it can stress or inhibit bacterial populations, yielding misleading test results. For instance, certain pathogenic bacteria may decline in numbers in acidic or basic conditions, affecting detection.

Given that both temperature and pH significantly influence bacterial viability and growth dynamics, the correct choice is indeed that both factors affect the accuracy of bacterial testing in water. This emphasizes the need for careful control and consideration of these variables when conducting such tests to ensure reliable results.