What minimum number of performance audit samples must certified labs analyze annually?

Certified labs are required to analyze a minimum of one performance audit sample annually. This requirement is essential for maintaining the lab's accreditation status and ensuring that the lab's testing methods and equipment are functioning properly. Conducting at least one performance audit sample allows for the evaluation of the lab's precision and accuracy in testing, providing confidence in the results that they report.

Performance audits help to identify any potential issues in laboratory practices or equipment that could affect the integrity of water testing results. By analyzing a minimum of one sample, the laboratory can demonstrate its capability to produce reliable and valid data, which is crucial for protecting public health and ensuring compliance with water quality regulations.

While higher numbers of performance audit samples can enhance the verification process, the minimum requirement set by regulations is one sample per year. This ensures that labs are regularly assessed without imposing overly burdensome requirements that could hinder their operations.