Features of evaluation drift effect during Key Comparison COOMET.EM-K5

Abstract

Results of pilot laboratory and participating laboratories which are measuring the same travelling standard during Key Comparison must be most similar. However, this may not always be possible, because the travelling standard which is sent in turn to all participating laboratories is not always perfectly stable. So that it is necessary to take into account the drift effect of the travelling standard. The article describes some problems concerning the evaluation drift effect of travelling standard and its further influence on evaluation key comparison reference value during Key Comparison. The procedure for evaluation drift effect when its model can be linear or not linear was presented. Comparative analysis of the proposed procedures for evaluation drift effect is applied to the Key Comparison of Power COOMET.EM-K5 was done.