Comparison of Standards for Testing Electrical Dishwashers or Dishwashing Detergents

Abstract

This study presents an overview of four international test standards for domestic dishwashers or dishwashing detergents: the European (EN 50242), the North American (AHAM), the Australian (AS/NZS) and IKW standard. All four standards were used to test five different dishwashers and two kinds of dishwashing detergents under standardised laboratory conditions to see if they deliver comparable results. Furthermore the practicability and selectivity of the different soiling and evaluation procedures were assessed. Additionally to a general comparison of the four standards, the focus lay on the soil egg yolk. The study shows that the general ranking between the dishwashers is similar, but the cleaning results of the individual soils and the performance levels differ a lot. Only the IKW soils are suitable to make a clear distinction between the detergents. Whereas the machines can be – more or less – distinguished with all standards except AS/NZS standard. Possible reasons for the varying results can be found in the different amounts of soil, the preparation methods or the cleaning performance evaluation, which shows the importance of designing accurate testing procedures for dishwashing.