Quality control of the laboratory environment

A laboratory performing U and Pu analysis for safeguarding of legal limit compliance has to demonstrate the utmost care to avoid any sources of cross-contamination and source deterioration during sample handling to satisfy the customers' requirements. An example is given, from the IAEA Safeguards Laboratory in Seibersdorf, how a clean room is designed to accommodate the TIMS facilities for U and Pu analysis in the femto- or attomole range. Continuous blank monitoring and particle counts are mandatory to ensure absence of any accidental sources of contamination. (author)