Interpreting a Laboratory Quality Control Report
Michael Doucet (ALS Canada Ltd.)

Many water and wastewater operators are quite experienced in receiving analytical results and interpreting if they pass a particular guideline or criteria, or not. However, many operators may not understand what laboratory processes are involved in evaluating the quality of the results prior to issuing the report. ALS is an international testing firm with locations in Dartmouth and Fredericton. ALS will present on what components of the laboratory results operators should be reviewing to evaluate if the results meet their internal quality requirements. ALS will primarily speak to common quality control type samples that often include method blanks, duplicates, laboratory control samples, matrix spikes surrogates and reference material. ALS will include the purpose of the sample, how the laboratory uses the data, and how the operator should be considering these results. ALS will also discuss data quality objectives and compliance ’– how does the laboratory typically manage quality control results that fall outside the control limits. ALS will also review other important quality control items that are evaluated for compliance like adherence to analysis holding time that is specific for each analysis, the type of bottle the sample was collected in, and quality control sample frequency.