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Procedures for Detection and Quantitation
Federal Advisory Committee on Detection and Quantitation for Uses in Clean Water Act Programs
Meeting #11
Batch Verification
The Technical Work Group held two meetings as authorized by the Committee at the September 19-21 Committee meeting. The Work Group discussed batch verification and developed language intended to fit into the DQFAC Single Laboratory Procedure v 2.4 in section 2.2 under ongoing verification. Please refer to the language shown below.
This language, and the Technical Work Group's discussion around it, is meant to be presented at the December 5-6 FACDQ meeting as requested by the Committee. It is expected that the portion of time devoted to this item will be short because there is no action needed by the Committee and the Committee's need to focus on finalization of the Final Report.
While no vote or action is expected to be taken by the Committee, the meeting summary will document the discussion.
2.2. Optionally, perform a statistical process control evaluation of the available data base of method blanks and DL check samples to determine rates of false positives and false negatives. Such checks should be performed on a minimum of 7 values and preferably 20 or more values. If the false positive rate or false negative rate indicates an on-going problem (e.g., either exceeds 5%), re-evaluate the DL and/or QL as appropriate.