SI-TRACEABLE VALUES FOR CADMIUM CONCENTRATION IN THE WATER SAMPLES OFIMEP-6

The certification measurement for the cadmium concentration in the sam ples as performed by Isotope Dilution (ID) using inductively coupled P lasma Mass Spectrometry (ICP-MS) is described in framework of the Inte rnational Measurement Evaluation Programme (IMEP). By using a primary method of measurement (ID), making up a full uncertainty budget and us ing a sensitive technique (ICP-MS), reference values traceable to SI c an be obtained for this material. The uncertainty budget is performed in accordance with the ISO and EURACHEM guides on uncertainty. A compa rison is made with certification results of other experienced laborato ries also using primary methods where possible.