Quality control in the low activity radioanalytical laboratory of the Environmental Division, DIEAM.CN of NUCLEBRAS Research Center - CDTN

The Environmental Engineering Division - DIEAM.CN of NUCLEBRAS research center - CTDN, is in charge of the routine work related to the analysis of environment samples collected at several NUCLEBRAS facilities. This paper presents the procedures used for quality control of the analyses performed at the Laboratory. The samples are initially verified and recorded as soon as they arrive at the Division. From then on, each aliquot and each analysis will be controlled using a follow-up sheet. Once a year, the operational conditions of the Lab couting systems are verified thoroughly. At that time, the systems are calibrated using certified radioactivity standards. Performance of the detectors is checked using control graphs, which can indicate the need for specific procedures to be followed such as maintenance, decontamination or recalibration. In order to reduce the risk of mistakes and to increase the capacity for global data evaluation, a microcomputer is used for processing the counting data and for editing a final report. (author)