Abstract
KAN proficiency testing program on the bottled drinking water conducted on 2004 was participated by 46 testing laboratories. Participant laboratories were asked to test the sample for nitrat, nitrit, ammonium, sulphate Cl, Cn, F, F, Fe, Mn, Pb, Cu, Cd, As and Hg contents. Proficiency testing sample were prepared by provider, which also conduct homogeinity test for the Hg and Cu contents of the sample. As the sample was judged to be homogen, they sent to participant laboratory in 2 packs identified as sample KAN A and KAN B. Laboratory testing results were analyzed by statistical method, started on homogeinity of data, Dixon test and Z-score. The evaluation results shows that only sulphate, Cl, F, Fe and Cu contents could be analyzed among the other 14 parameters, which is could not be evaluated because of the in homogeinity of data provided by the laboratories. The inhomogeinity of data was caused by insufficiency of laboratory’s personnel and equipments. The evaluation of proficiency testing results for sulphate, Cl, F, Fe and Cu contents show only 1 satisfactory result among 5 accredited participants, and 9 satisfactory results among 39 non-accredited participants. The conclusion is based on the Z-score analysis of the evaluated parameters.
Keywords
proficiency testing, testing laboratory, bottled drinking water, parameter to be tested
References
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