Proftest SYKE carried out the proficiency test in cooperation with KVVY Tutkimus Oy for the laboratories conducting leaching tests for solid waste material in May-June 2020. The results of the two stage batch leaching test (EN 12457-3) for samples of treated slag from waste combustion were compared and evaluated. The tested measurands were metals (As, Ba, Cd, Cr, Cu, Hg, Mo, Ni, Pb, Sb, Se, V, Zn), Cl-, F-, SO42-, DOC, pH, conductivity, and TDS. In total, 13 participants joined in the proficiency test.

In this proficiency test either the robust mean or the median of the results reported by the participants was used as the assigned value. The results were evaluated both with z and En scores. When deviation of 10–35 % or 0.3-0.4 pH units was accepted from the assigned value, 85 % of the results evaluated with z scores were satisfactory. Of the results evaluated with En scores, 80 % were satisfactory.

Warm thanks to all the participants of this proficiency test!