How many service connections upstream must be resampled if a micro test fails?

When a micro test fails, the protocol typically requires greater scrutiny to identify potential sources of contamination and ensure water safety. Resampling is an essential step in this process, and the number of service connections to be resampled is guided by established standards.

Choosing to resample five service connections is based on the need to thoroughly investigate the extent of the issue. Sampling a larger number of connections increases the likelihood of detecting contaminants that may not be present in a single sample. It provides a broader representation of the water quality and assesses the potential reaches of contamination upstream of the test site. This practice helps ensure that the water supply remains safe for consumers and that any problems are resolved effectively.

The guidelines set forth by regulatory agencies help ensure that adequate measures are taken to protect public health, emphasizing the importance of the resampling process when a micro test indicates a failure.