|Julkaisusarja ja numero:||7/2018|| |
|Kustantaja:||Suomen ympäristökeskus|| |
|Tekijät:||Mirja Leivuori, Riitta Koivikko, Timo Sara-Aho, Teemu Näykki, Keijo Tervonen, Sari Lanteri, Ritva Väisänen and Markku Ilmakunnas|| |
Proftest SYKE carried out the proficiency test (PT) for elemental analysis of waste waters and sludge in October 2017 (MET 10/2017). The measurands for the synthetic samples were: Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, V, and Zn. These measurands were also analysed from the waste water samples as well as measurands B, Ba, Ca, Mg, Mo, Sb, Sn, Sr, and Stot. In addition to the aforementioned, also measurands Ntot, Ptot, and dry weight were analysed from the sludge sample. In total 26 laboratories participated in the PT. In this proficiency test 91 % of the results were satisfactory when deviation of 5 – 30 % from the assigned value was accepted.
Basically, either the metrologically traceable concentration, calculated concentration, the robust mean, mean or median of the results reported by the participant was used as the assigned value for measurands. The evaluation of the performance of the participants was carried out using z scores. In some cases the evaluation of the performance was not possible e.g. due to the low number of the participants or the high deviation of reported results. There, when possible, D% scores were calculated. Warm thanks to all the participants of this proficiency test.