ABSTRACT
This chapter briefly presents an overview of the importance of reference materials while focusing on how to perform meaningful testing in their absence by using alternative techniques such as the production of in-house reference materials and participation in quality assurance (QA) programs. Participation in QA programs allows laboratories to demonstrate accuracy-based performance and assess and improve measurement accuracy, precision, and comparability using certified reference materials, non-certified reference materials, or other test materials. Discussion and evaluation of the sample preparation and analytical methods used by different laboratories is a major focus of QA programs, and extensive final reports are distributed to the participants to discuss approaches to improve performance. In general, participation in any type of interlaboratory comparison can be beneficial to a laboratory and improve overall performance and confidence in measurements, which in turn increases the confidence in testing of routine samples for ensuring product safety.
