Dishwashing with modern automatic dishwashers saves resources. Their efficiency is enhanced continuously, to reach even lower water and energy consumption values. But it is mainly manual dishwashing, with varying techniques, that is being conducted across the world. Mostly they have one thing in common though: very high water consumption. A research team of the Institute of Agricultural Engineering at the University of Bonn has developed recommendations on how to save resources when washing dishes manually. These recommendations focus on dishwashing in two sinks: One with warm water, for soaking and cleaning, and one with cold water for rinsing. To make it more efficient (with respect to time, water, detergent and energy) and more hygienic dishes shall be collected throughout the day and get dried without a towel.
In preparation for this dissertation a pre-study was run to gain insight into the common dishwashing techniques of housewives in nine different countries (Latin America, Europe and Asia). The results show clear discrepancies between the dishwashing recommendations and the currently common behaviour. But how do housewives rate the recommendations, when they are asked to apply the rules in spite of that and what is their experience and/or understanding of their benefits within this process? This was assessed by running a fieldwork study with housewives in Indonesia, Thailand and Argentina. Throughout a test period of one week housewives were asked to apply the optimized dishwashing recommendations, the so called “Best Practice Tips” (a final set of nine rules). The documentation of the application in a diary combined with the feedback given afterwards shows: The rules are applicable but the housewives criticize the extra effort. In Argentina this extra effort is lowest, as they have warm tap water and a sink available. But there is a lack of space for arranging a second one. In Indonesia and Thailand, the water needs to be heated in a kettle and two basins must be arranged. This leads to uncomfortable working positions on the ground floor in many cases. Therefore, the recommendation to make use of two sinks was seen as an obstacle when it comes to application of the Best Practice Tips in all visited countries. This recommendation can’t be changed when reworking the Best Practice Tips, as it is essential for water saving. Thus, this thesis shows obstacles when it comes to implementation of the Best Practice Tips in daily life. The experienced discomfort during application needs to be justified with good counter arguments. Further application studies could compare the effect of different arguments, for example sustainability, costs, time consumption and hygiene.


Moderne automatische Geschirrspülmaschinen reinigen Geschirr ressourcensparend. In der Realität wird das Geschirr jedoch in großen Teilen der Welt manuell gereinigt und dabei auf verschiedenste Reinigungstechniken zurückgegriffen. Diese haben zumeist eins gemeinsam: Es wird sehr viel Wasser verbraucht. Ein Forschungsteam des Instituts für Landtechnik an der Universität Bonn hat in Labor- und Feldversuchen eine wassersparende Handspültechnik entwickelt. Die Spülempfehlungen heben das Spülen in zwei Becken als zentralen Kern hervor.
Im Rahmen dieser Dissertation wurde zunächst eine Vorstudie durchgeführt, die eine Beschreibung von aktuellen Spültechniken erlaubt. Es zeigte sich: Die Spülempfehlungen stehen größtenteils im Widerspruch zu den aktuellen Spültechniken. Doch wären die Hausfrauen dennoch bereit diese Empfehlungen umzusetzen, wenn sie diese ausprobieren und die Vorteile verstehen oder erleben würden? Dies wurde in einer Feldstudie mit Hausfrauen in Indonesien, Thailand und Argentinien erprobt. Über eine Woche hinweg wandten die Hausfrauen die optimierten Spülempfehlungen, die sogenannten Best Practice Tips an. Die Dokumentation der Anwendung und das danach gegebene Feedback zeigen, dass die Regeln anwendbar sind, die Hausfrauen die Anwendung jedoch häufig als aufwendiger ansehen.

Schlagwörter: Sustainability; Dishwashing; Intervention Study

Schriftenreihe der Haushaltstechnik Bonn