Quality assurance considerations in chemical analysis

Quality Assurance (QA) for an analytical laboratory is an essential tool to ensure good comparability of data. In order to achieve this purpose, processes are monitored and performance problems are systematically solved. A variety of texts exists such as Good Laboratory Practice and the Quality Assurance Systems ISO 9001 and ISO 17025. However, these international standards provide only general rules to install and maintain a quality system. It remains the responsibility of the laboratory to define appropriate procedures to ensure that proper quality is achieved. Adherence to QA guidelines, participation in inter-laboratory studies, use of reference materials (RM) and certified reference materials (CRM) are all means of achieving good data quality for determinations.