In a water sampling scenario, what action should be taken if the second sample shows low results?

In a water sampling scenario, if the second sample shows low lead results, letting the water run cold before re-sampling is a prudent action. This step is important because lead can leach into the water due to plumbing materials when water has been sitting stagnant in pipes. By allowing the water to run for a short time before collecting a sample, it ensures that any lead that may have accumulated in the tap is flushed out, allowing the sample to reflect the actual lead level in the water supply more accurately.

This method is a common practice in lead testing to get a clearer picture of the water quality. Not only does it help mitigate any potential inaccuracies caused by stagnant water, but it also ensures the sample reflects the water that is actually being consumed rather than water that has had time to sit in contact with plumbing materials.