If there is no chlorine ______ at a faucet, what should you do?

Flushing longer at a faucet when there is no chlorine detected is the correct approach because it helps ensure that the water being sampled is representative of the water quality coming from the entire distribution system. Chlorine is a critical indicator of disinfection efficacy, and its absence may suggest that the water has not been adequately treated or has stagnated in the system. By flushing for an extended period, you allow fresh water to flow from the main supply, which is more likely to contain the appropriate chlorine residual and reflect the actual disinfection state of the water. This step is essential for accurate sampling, as it reduces the impact of any stagnant water that might have chlorine levels significantly lower than what is expected in the distribution system.