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Despite the fact that dishwashers have been optimised in recent decades in response to policy requirements, consumers still use more energy and water than necessary. This has been deeply investigated by two research groups with complementary approaches and published in this journal. When translating these scientific findings into recommendations, it is essential to ensure that these recommendations can be easily integrated into consumers’ everyday lives and do not lead to significant failures or disappointments that result in compensatory behaviours among consumers and consume even more resources. In this context, the authors suggest the introduction of a ‘short eco’ programme, which is just as economical as the ‘eco’ programme, but, achieves similar cleaning results in a much shorter time when using a high-performance detergent. This would overcome one of the biggest limitations that consumers currently have when using the ‘eco’ programme. The authors discuss the possible consequences of this proposal and invite readers for comments.

Routine household tasks, such as laundry or dishwashing, are complex socio-technical systems in which a variety of factors and actors interact, including manufacturers, technologies, regulators, consumer practices, cultural norms and infrastructures. A deep understanding of these socio-technical systems is necessary to find the right recommendations on how to optimise this system in order to achieve relevant savings in resource consumption without requiring a complete renewal of the infrastructure installed. In our case, we focus on automatic dishwashing in the United Kingdom and try to find out what an optimised consumer use of the dishwashers installed can look like and how many savings can be achieved. Accordingly, we modelled the base of dishwashers installed and conducted a consumer survey on dishwasher usage behaviour in sufficient detail to understand the interplay between the various factors. By simulating a change in usage behaviour, we find a potential energy saving of 21.3 % simply by following basic rules for selecting the appropriate programmes without the risk of a loss of performance.

The laundry process is energy-intensive and an important target for reducing residential environmental impacts. Category life-cycle analysis (LCA) studies show the primary environmental impact is due to the energy consumed during the use phase, mainly for heating water. However, doing the laundry is a complex socio-technical system, where addressing sustainability requires not only technical levers but also an understanding of users’ habits, practices, and belief systems. This study investigates if and how consumers change their laundry habits and product satisfaction when using a technically lower-performing eco-brand detergent compared to a heavy duty high-performance detergent. These represent two distinct sustainable innovation strategies within the detergent industry, i) high-performance detergents formulated to provide excellent cleaning performance at lower wash temperatures and ii) eco-brand detergents optimized for a lower ingredient footprint but reducing cleaning performance. It is hypothesized that consumers may compensate in ways detrimental to the overall sustainability of the laundry lifecycle. The results showed significantly lower consumer satisfaction with the eco-brand performance which led to compensatory behavior including increased detergent dosing and higher wash temperatures. This study confirms the importance of detergent cleaning performance for sustainable consumer habit changes regarding lower wash temperatures.

Automatic dishwashers combine capital, energy, and water to provide a relevant household service, namely dishwashing. Consumer behaviour in using the automatic dishwasher influences to a great extend the environmental impact of such a device. But what simple and intuitive recommendation can be given to consumers to save energy and water while maintaining the cleaning performance? This task is investigated by modelling the resource consumption for automatic dishwashers in six European countries by considering the installed base of automatic dishwashers and recently surveyed consumer programme selection behavior. Using this model, a simulation is performed on how three simple recommendations on the programme selection would affect the overall consumption. As a result, more than 20% of the consumed energy can be saved by following these simple recommendations. To facilitate consumers’ actual adoption of the recommendations, this publication presents effective communication measures based on the science of consumer behaviour.

Automatic dishwashing has been optimised in manifold ways during the last decades: new dishwashing devices (e.g. optimised for best class in energy labelling) and innovative dishwashing detergents (e.g. with advanced enzyme technologies). However, the usage of the automatic dishwasher in consumers’ home may not be adequate to gain all the benefits from these developments. Little is known about the actual consumer behaviour with automatic dishwashing. This was tried to solve by performing a survey on the consumer behaviour on automatic dishwashing in Germany, Italy, Spain, Poland, Hungary and Turkey covering large parts of Europe. The results show that the ‘eco’-programme is getting more importance in programme selection. However, feedback on the soil level of the dish items put into this programme and the observed duration of the programme show that the potential of the ‘eco’-programme is not fully utilised by consumers. Besides this, the survey delivers relevant details on differences which may help to understand the needs and wishes of consumers in those countries.

Automatic dishwashing is an example of a complex socio-technical system with an interplay between a variety of factors and participants, including manufacturers, technology, regulators, consumer practices, cultural norms and infrastructure. Understanding this system is a prerequisite to find the right levers to optimise it. In this context, automatic dishwashing in Australia is studied by modelling the installed base of dishwashers in Australian households and recording the consumer usage of dishwashers in detail in a representative way. The information from both combined allows one to estimate the actual average use of resources (energy, water) and programme duration of dishwashers. Analysing the consumer behaviour opens the way to find optimisations of the consumer behaviour which would allow a saving of resources (more than 20 % on electrical energy) without deteriorating the performance and practical use of the dishwashers. Moreover, the comparison of the Australian socio-technical system around automatic dishwashers with the European system allows one to find a possible saving of another 20 % on energy caused by differences in the regulatory framework for those appliances.

Every day, dirty dishes and cutlery have to be cleaned in millions of households worldwide. From a scientific point of view, the question of “how” is particularly interesting, because everyday household chores hold great potential for saving resources. This review summarises the current state of knowledge about dishwashing. In general, electric dishwashing proves to be significantly more resource-efficient than manual dishwashing, with comparable or better cleaning results. However, the extent of this depends on consumer behaviour. Therefore, best practice tips (BPT) for manual and electric dishwashing as well as ideas for educating consumers are also collected in this review.

The current state of knowledge about hygiene (efficacy testing) in commercial dishwashers will be collated in this review. Therefore, studies about hygiene in commercial dishwashing are summarised and existing standards, guidelines and the legislative basis described. Finally, examples of information available from the market, for example, detergents are presented. The use of bioindicators contaminated with bovine albumin, mucin, corn starch and Enterococcus faeciumis widely established in studies, which was the basis for the introduction of standards. Standards prescribe minimum temperatures for cleaning and rinsing, and most of them provide microbiological testing methods. A worldwide standardized test method for hygiene in commercial dishwashers would guarantee the comparability of country-specific standards but procedures currently available would need great efforts to be unified. A definition of a specified hygiene target level on cleaned dish items would also be meaningful because a harmless level of microorganisms can be achieved with it regardless of the initial microbial count or the process used.

Near infrared (NIR) measurements have been used for several years to examine the processes taking place in the dishwasher during dishwashing. It is possible to differentiate between the soil components butterfat, oatmeal and egg-yolk and to determine their concentration in the dishwashing liquor quantitatively. Consequently, time-consuming dishwashing tests can be avoided by weighing the dishes. However, this method is also based on a small number of NIR measurements which are carried out intrusively during the dishwashing process, i.e. outside the dishwasher. These few NIR measurements make it difficult to investigate the dynamics of a dishwashing process. In this study, the development, testing and usage of a new online tracking measuring system is presented. The latter was used to perform 38 dishwashing processes, each containing 51 NIR spectra, to develop a calibration model using the partial least squares regression method with cross-validation. This new online tracking measuring system, based on the calibration, can determine the concentrations of three different soil components in the dishwashing liquor during automatic dishwashing. By recording the 51 spectra, it is possible to display a tracking curve for each soil component, i.e. the concentration courses of the dishwashing process over time. This results in a significantly better time resolution and it was possible to investigate the first dynamic part of the tracking curve, i.e. the beginning of the dishwashing process. This could lead to the opportunity to change the state of the dishwasher depending on the concentrations detected in the first step and, secondly, to a more environmentally friendly and cost-reducing dishwashing process.

Near infrared (NIR) measurements have been used for several years to examine the processes taking place in the dishwasher during dishwashing. It is possible to differentiate between the soil components butterfat, oatmeal and egg-yolk and to determine their concentration in the dishwashing liquor quantitatively. Consequently, time-consuming dishwashing tests can be avoided by weighing the dishes. However, this method is also based on a small number of NIR measurements which are carried out intrusively during the dishwashing process, i.e. outside the dishwasher. These few NIR measurements make it difficult to investigate the dynamics of a dishwashing process. In this study, the development, testing and usage of a new online tracking measuring system is presented. The latter was used to perform 38 dishwashing processes, each containing 51 NIR spectra, to develop a calibration model using the partial least squares regression method with cross-validation. This new online tracking measuring system, based on the calibration, can determine the concentrations of three different soil components in the dishwashing liquor during automatic dishwashing. By recording the 51 spectra, it is possible to display a tracking curve for each soil component, i.e. the concentration courses of the dishwashing process over time. This results in a significantly better time resolution and it was possible to investigate the first dynamic part of the tracking curve, i.e. the beginning of the dishwashing process. This could lead to the opportunity to change the state of the dishwasher depending on the concentrations detected in the first step and, secondly, to a more environmentally friendly and cost-reducing dishwashing process.

The requirements for commercial dishwashers differ fundamentally from those for domestic dishwashers. For commercial dishwashers, capacity and programme duration are the main factors. Accordingly, different designs are offered for the different types of requirement. Comprehensive data on the usage behaviour of commercial dishwashers is scarcely available. Within the framework of face-to-face interviews, 200 companies in Germany and Denmark were visited to record their user behaviour. With the help of the data obtained, not only errors in the usage behaviour were found, but also indications of unnecessarily high water and energy consumption, which, inter alia, lead to increased costs for the companies. The results show that manual pre-rinsing in particular leads to increased water consumption. Furthermore, the dishwashers are only partially loaded, which leads to more wash cycles than necessary. In order to ensure the optimal utilisation and correct user behaviour of commercial dishwashers, while simultaneously reducing the impact on the environment, there is an urgent need to educate users better on how to use them correctly.

The 'Recommendations for the Quality Assessment of the Cleaning Performance of Dishwasher Detergents" provide detailed procedures to assess the performance of a household dishwasher detergent using a standard test programme of a standard dishwasher. As such, they are a de facto standard for a whole industry. Consequently, it is relevant to ensure that the conditions under which the tests are carried out represent the relevant market: the automatic dishwashing machines installed and used in households in Europe. But no data are available by now describing the situation in the households. The task here is to model the distribution of total energy, water consumption and programme duration of the automatic dishwashing machines installed and used in private households in Europe when used by the consumer. Those data are then compared to the data of the reference dishwasher and, thus, the relevance of the reference system to the dishwashers installed in private households is assessed.

The aim of this study was to establish a simple model describing the microbial reduction of a cleaning process by only using physical parameters of a given cleaning process (time and temperature) together with microorganism-specific inactivation parameters. The \Microbiological Inactivation Equivalent (MIE) unit" representing the time-temperature integral of a dish treatment process for a specific microorganism was developed. Microbiological reduction in suspension and dishwasher tests was tested in parallel. The microorganism-specific inactivation parameters were adjusted by fitting the MIE units to the experimental reduction factors gained. The mean square deviation between reduction factors and MIE units calculated was on average < 1 (Enterococcus faecium: 0.87, Micrococcus luteus: 0.79) in suspension tests and 1.09 (Enterococcus faecium) and 1.03 (Micrococcus luteus) in dishwasher tests. The MIE model can be used as a simplified method to predict the hygienic performance of a specific cleaning process under well-defined conditions.

The aim of this study was to establish a simple model describing the microbial reduction of a cleaning process by only using physical parameters of a given cleaning process (time and temperature) together with microorganism-specific inactivation parameters. The \Microbiological Inactivation Equivalent (MIE) unit" representing the time-temperature integral of a dish treatment process for a specific microorganism was developed. Microbiological reduction in suspension and dishwasher tests was tested in parallel. The microorganism-specific inactivation parameters were adjusted by fitting the MIE units to the experimental reduction factors gained. The mean square deviation between reduction factors and MIE units calculated was on average < 1 (Enterococcus faecium: 0.87, Micrococcus luteus: 0.79) in suspension tests and 1.09 (Enterococcus faecium) and 1.03 (Micrococcus luteus) in dishwasher tests. The MIE model can be used as a simplified method to predict the hygienic performance of a specific cleaning process under well-defined conditions.

The 'Recommendations for the Quality Assessment of the Cleaning Performance of Dishwasher Detergents" provide detailed procedures to assess the performance of a household dishwasher detergent using a standard test programme of a standard dishwasher. As such, they are a de facto standard for a whole industry. Consequently, it is relevant to ensure that the conditions under which the tests are carried out represent the relevant market: the automatic dishwashing machines installed and used in households in Europe. But no data are available by now describing the situation in the households. The task here is to model the distribution of total energy, water consumption and programme duration of the automatic dishwashing machines installed and used in private households in Europe when used by the consumer. Those data are then compared to the data of the reference dishwasher and, thus, the relevance of the reference system to the dishwashers installed in private households is assessed.

The aim of this questionnaire survey study is to find out if the three socio-demographic aspects gender, age and household size have any influence on washing-up behaviour and whether people's washing-up behaviour changes due to them. The data was collected via a questionnaire created and carried out by “Forum Waschen” that could be answered by German consumers either on the internet or on the day of sustainable washing created by “Forum Waschen”. In addition to the socio-demographic facts, the questionnaire involved questions about both manual and automatic dishwashing. The results of this study vary; some aspects of washing-up behaviour are correlated and some are not. Only some aspects are dependent on gender, more the manual dishwashing behaviour than the automatic. By contrast, most aspects depend on or correlate with the participant's age. The biggest difference between households of different size are the quantities of dishes used and need to be washed per day. Besides the connections to socio-demographic aspects, there are also connections between different aspects of dishwashing behaviour itself, such as the positive correlation between the frequency of changing the tea-towel and its usage.

Automatic dishwashing is a process which takes enormous amounts of resources (energy, water, chemicals). However, most of the dishwashing programs are designed and tested to clean the worst scenario for a certain kind of load items (glass, porcelain, etc.) and do not or only partly adapt to the actual load and soiling conditions. Thus, resources are wasted which could be avoided if a better adaptation to the actual status of the dishwashing process would be possible. It is, therefore, the aim of this study to investigate the possibility of using near-infrared technology to evaluate the status of the dishwashing process by analyzing the content of soil components already dissolved in the dishwashing water. Compared to other methods, the main advantage of near-infrared measurements is the possibility to differentiate between soils or soil components (carbohydrates, fats and protein) at very low concentrations. Near-infrared spectroscopy implemented in an automatic dishwasher could observe and evaluate an automatic dishwashing processes by using online measurements of the detachment of soils from soiled dishes. Thirty-seven model emulsions containing detergent, tap water, different soils and soil concentrations were created and measured by using near-infrared spectroscopy to demonstrate its suitability for the evaluation of dishwashing processes. The spectra were the basis of developing near-infrared calibration models for each soil component using the partial least squares regression method with internal cross-validation. The coefficients of determination in internal cross-validation (R²) are 0.88 for carbohydrates, 0.92 for fats and 0.99 for proteins. Thereafter, the calibration models developed were externally validated with samples of known concentrations of these soil components. The known concentrations were determined during external validation. The results of calibration and evaluation show that it is generally possible to measure very low concentrations of soil components in dishwashing liquor. The applicability to a real dishwashing process and the usage of other soils has yet to be tested.

The European energy label was established to reduce energy consumption in Europe. All classes and values on the energy label are stated by the supplier. The task of market surveillance is to ensure correct labels and to validate their values through compliance tests. However, this can only be done for a small fraction of all models on the market, since physical tests are expensive. Screening methods can be used to narrow down the number of critical products before compliance tests are done to decrease the costs of finding non-compliant models. This study shows a mathematical approach to analyze the cost benefits of screening methods to find non-compliant models. Furthermore, the analysis presented has been applied to 18 screening methods for tumble dryers. The performance test for tumble dryers consists of seven test runs. All screening methods evaluated are composed of a reduced number of test runs. The most efficient screening method reduces the surveillance costs by 40%.

The purpose of this study was to utilize NIR spectrometry to develop a novel method to detect and determine concentrations of different soils in dishwashing liquor during automatic dishwashing in real-time. If it is possible to differentiate between soils, this could be an opportunity to react specifically to them (e.g. by increasing the water temperature if fat components are not sufficiently emulsifying). The possibility of an automatic adaptation of the dishwashing process to different soils and soil levels could lead to a shorter, more environmentally friendly and cost-reducing process. In a first approach, an emulsion containing three soil types (oatmeal, egg-yolk and butterfat), water and detergent were used to develop NIR spectrometry prediction models. Transmittance spectra obtained with an Fourier transform near infrared (FT-NIR) spectrometer of testing standards of 76 automatic dishwashing cycles with seven samples per cycle were taken at various times during the main washing process for calibration (and validation) of the NIR spectrometry prediction models. The spectra were pretreated to develop NIR spectrometry prediction models for each type of soil using the partial least squares regression method with cross-validation. Overall, the coefficients of determination in cross-validation are R2 > 0.92 for all NIR spectrometry prediction models developed. The results of the prediction models developed show that NIR spectrometry technology is a promising method to predict different levels of predefined soils in dishwashing liquor. The NIR spectrometry models were applied to an automatic dishwashing process with soiled dishes instead of emulsions containing soils to test their applicability. The resulting dishwashing process could be tracked in real-time by the dissolved soil concentrations, observed in the dishwashing liquor.

The purpose of this study was to utilize NIR spectrometry to develop a novel method to detect and determine concentrations of different soils in dishwashing liquor during automatic dishwashing in real-time. If it is possible to differentiate between soils, this could be an opportunity to react specifically to them (e.g. by increasing the water temperature if fat components are not sufficiently emulsifying). The possibility of an automatic adaptation of the dishwashing process to different soils and soil levels could lead to a shorter, more environmentally friendly and cost-reducing process. In a first approach, an emulsion containing three soil types (oatmeal, egg-yolk and butterfat), water and detergent were used to develop NIR spectrometry prediction models. Transmittance spectra obtained with an Fourier transform near infrared (FT-NIR) spectrometer of testing standards of 76 automatic dishwashing cycles with seven samples per cycle were taken at various times during the main washing process for calibration (and validation) of the NIR spectrometry prediction models. The spectra were pretreated to develop NIR spectrometry prediction models for each type of soil using the partial least squares regression method with cross-validation. Overall, the coefficients of determination in cross-validation are R^2 > 0.92 for all NIR spectrometry prediction models developed. The results of the prediction models developed show that NIR spectrometry technology is a promising method to predict different levels of predefined soils in dishwashing liquor. The NIR spectrometry models were applied to an automatic dishwashing process with soiled dishes instead of emulsions containing soils to test their applicability. The resulting dishwashing process could be tracked in real-time by the dissolved soil concentrations, observed in the dishwashing liquor.

The ubiquitous finding of microplastic in the abiotic and biotic environment has gained a lot of attention recently in the media, scientific community and among the general public. One of the known sources of microfibres is the washing of textiles. It would be a conceivable option to install filters in domestic washing machines that would sift out microplastics to prevent this pollution. The aim of this paper was to conduct a comprehensive literature search on microplastics filters in washing machines published already. Although the results of this research show that there has been an effort to find solutions for this problem in a worldwide context, there has been no known proven system that prevents microfibre release in the aquatic environment which does not have a harmful influence on the washing behaviour and/or washing results.

There is a large influence of consumer behaviour on the resource consumption of owners and non-owners of automatic dishwashers. Therefore, it was the task to explore what kind of habits and intentions of consumers in Europe can be identified which restrict the consumer from using an automatic dishwasher, either not buying one or not using it, although it is available in the household. This was carried out on a representative level with a sufficiently high number of participants to avoid conclusions being taken on a statistical basis that is too small. The question is answered from different perspectives: Why do owners of an energy efficient automatic dishwasher not use it properly and what arguments do non-owners have for not buying one?

The private household sector utilises a large contribution of the global energy and water resources. Household appliances have been developed to be increasingly efficient and resource saving. The efficiency of the appliance itself and consumer behaviour have an influence on the real-life usage of resources. A calculation module was created to help the consumer understand which part of their behaviour related to what amount of energy and water resources and associated costs are produced. With this module, the complete laundry and dishwashing processes could be covered and a personalised feedback on the use of water and energy and the associated costs could be generated. This module of a resource calculator has been available online on the website of Forum Waschen, a German multi-stakeholder association, since 2013. Input data from the users were stored anonymously with the consent of the user and analysed offline to learn about the actual consumer behaviour. A total of 2 049 useable datasets could be evaluated covering the years 2013 to 2016. They show that consumer behaviour is an important factor leading to the economizing of resources following the optimisation of the efficiency of household appliances. In some cases, households started to reduce the consumption and act resource saving. Some households now wash less, at lower temperatures, dry about 50 % of the laundry outside in the summer and iron less. They use mostly the energy-saving programme for automatic dishwashing and wash only necessary things in a sink filled with warm water. In other cases, households are careless and do not think about their behaviour. They wash their laundry and dishes more often than necessary in half-loaded machines and use resource-consuming programmes at high temperatures. Moreover, they dry the laundry in heated rooms and iron all or most of their laundry. Additionally, they practice inefficient handwashing of dishes under hot running tap-water. Careless households can start to act sustainably when undertaking household activities to reduce their consumption and save resources and costs by paying more attention to the environmental impact and responsibility and changing their behaviour. Utilising the resource calculator, the user can simply see the consequences of a changed behaviour in terms of energy or water saved or lower associated costs. The consumer may be triggered to change their behaviour towards a more sustainable use of the resources with this kind of nudging providing personalised information.

Product testing is widely used to assess the characteristics, e.g. performance and energy consumption of a product. The procedures for executing the tests, including measurements and processing of measurement results, can be contained in standards. Standards should produce results that are repeatable, reproducible and valid at a reasonable cost. A number of stakeholders have questioned the appropriateness of several standards because the results that these standards provide are different from what a consumer may experience in practice. In the end, this can have negative consequences for the trust of consumers in the policy instruments (energy labels, minimum efficiency requirements) that use these standards and an energy savings deficit compared to what was expected by policy-makers. There is, therefore, a need for standards that better reflect ‘real-life’ conditions, meaning those conditions that consumers experience at home. However, unlike the other criteria that standards should meet, there is no methodology to assess the representativeness of a standard. This article develops such a methodology and presents the results for several household electrical appliances: washing machines, refrigerators and vacuum cleaners. In general, variation of situational conditions is not reflected in the standards and important parts of use behaviour are implemented as ‘artificial’ in the standards, showing that the other criteria (repeatability, reproducibility and cost) are prioritised over representativeness. Assessment of performance is difficult to evaluate because the type of assessment differs between practice and test; additional research is needed in this area.

Even though the duration of usage of large household appliances is found to be an average of 13 years in Germany, the data also shows that the proportion of large household devices which are already defective within the first five years has increased in the last decade. Material, functional, psychological and economic obsolescence are defined and discussed to explain this behaviour. The aim of this study is to identify consumer behaviour and motivation in the use and disposal of two major household appliances. Furthermore, whether the devices were disposed for reasons of economy, functionality or defect will be determined. A survey of 1,972 respondents was run online and on paper to collect quantitative data about consumer behaviour regarding the disposal of household appliances such as washing machines and dishwashers throughout their lifecycle in Germany. The data gathered will help to clarify if there is a connection between the disposal principle and the device price category and age. It was found that the main reason for disposal of a device is a defect, which is mostly not repaired because of additional costs which might be higher compared to a new purchase when the lifecycle is considered.

Water and energy dissipation is a remaining problem in the world and dishwashing is contributing to this. The correct cleaning technique can help to save resources, but needs to be promoted, as consumers tend to clean without thinking a lot about their technique. A global consumer survey was carried out and helped to identify common mistakes in dishwashing, which show the potential for improvement: Automatic dishwashers are partly rejected because of misunderstanding the big advantages. Furthermore, running cold tap-water is used frequently, and dishes are cleaned individually in manual dishwashing. Although the participants see themselves as interested in environmental topics, they are not aware of their personal potential to save resources during daily household work. This shows that the interest and the knowledge about sustainable dishwashing methods and the efficiency of automatic dishwashers needs to be increased.

Since the introduction of the energy label for household dishwashers in the EU, manufacturers have been incentivised to reduce resource consumption and increase the energy efficiency of their appliances. Technological progress has led to very efficient programmes with cleaning cycles of 3 to 4 h or longer. The European Commission recently initiated a revision of the energy label and Ecodesign requirements, leading to their adjustment to the state of the art and to actual usage patterns. The University of Bonn was tasked with investigating dishwashing habits in Europe. An online survey was conducted in 11 countries of the EU with more than 5000 participants. The survey focused on the choice of programme, attitudes towards energy-saving programmes and practices and the willingness to apply them. It appears that consumers are willing to apply energy-saving practices and to use energy-saving programmes, but the acceptance of long cycles that take more than 2 h is low, which stands in contradiction to the fact that 19% of all dishwashing cycles are run in the Eco programme, which takes more than 2 h in most cases. The percentage of people who understand that long cycles can be energy-efficient is smaller than the percentage of those who do not believe this. The statements of the participants are contradictory regarding the importance of saving energy and of programme duration. The results of the survey point out the importance of better consumer education and better communication by manufacturers, consumer organisations and legislation.

Each consumer is entitled to have hygienically clean processed dishes and cutlery. Consequently, restaurants, caterers, canteens, nursing homes, kindergartens and hospitals are very concerned to avoid infecting their customers and patients. They are afraid of the spread of diseases by inadequately washed dishes, glasses and cutlery. This study deals with the verification of the hygienic performance of commercial freshwater dishwashers with the aid of bioindicators that are contaminated with the test soil BAMS and two different strains of microorganisms: Micrococcus luteusand Enterococcus faecium. The method used is described in the working paper “WD 00429001 Commercial warewashing machines – Hygiene requirements and testing.” Tests for heat resistance are carried out to check the temperature interval of Micrococcus luteus. Thereby, it is shown that the germ examined still shows vitality at a temperature of 70°C and a holding time of ten minutes. When testing the hygienic performance of the dishwashing programs tested, it is shown that not only temperature, but also the effects of the detergent are recognizable.

Insufficiently decontaminated textiles could lead to transmission of infections. Thus, laundry hygiene is of particular interest and investigated in numerous studies. However, laundering experiments that use microorganisms to investigate the reduction of microbial loads on textiles are particularly time-consuming and material-intensive and the handling of pathogenic microorganisms is subject to legal regulations. Therefore, alternative methods of investigation are desired. So far, there is no satisfactory solution to assess the antimicrobial efficacy of a laundering process without expensive microbiological investigations. This study introduces an approach to predict the antimicrobial performance of a laundering process by its cleaning performance. It is not possible to conclude immediately from the cleaning index of a washing process to its antimicrobial effect based on stain types used in this study. Also in washing processes with low cleaning indices a high microbial reduction can be achieved. For bleach free liquid detergent, strong, time dependent, positive correlations between microbial reduction and cleaning index for cocoa, soot, and sebum were identified.

Reducing water temperatures in the wash phase of a washing programme and increasing the overall cycle durations are the latest trends in decreasing energy consumption of washing programmes, particularly for the so-called Standard programmes. This paper discusses the importance of saving energy in laundry washing, reasonable cycle duration for consumers and the link between saving energy and the duration of the wash cycle from a consumer point of view. This enables manufacturers to design appliances which are appreciated by the users. Information on consumers’ washing behaviour, experiences, habits and opinions concerning wash cycle duration was collected through a semi-representative survey in 11 European countries in 2015, with more than 5000 participants. The primary outcome of the study is that European consumers are willing to save water and energy in a laundry washing but are reluctant to use long programme cycles since they do not believe that the long cycles could be energy-saving.

Energy Labels are an instrument supporting on-going market transformation towards higher energy efficiency by motivating consumers to select more energy-efficient products. Since the purchase decision can be influenced by the consumers' understanding of the Energy Label, this paper addresses the clarity of the Energy Label of washing machines from a consumer's point of view, and their expectations and wishes concerning a future Energy Label. Information on consumers' opinions/expectations regarding the Energy Label was collected by a semi representative survey in eleven European countries in 2015. The main outcome of the study is that consumers are generally familiar with the symbols on the Energy Label, but they do not know this information belongs to which programme. They believe that a washing machine with the highest Energy efficiency class available on the market can help make savings on energy and water in all its programmes. Finally, the study suggests which modifications need to be applied to the current version of the Energy Label to improve its effectiveness.

Commercial dishwashers are used in community facilities such as hospitals, refectories, nursing homes or food services. In this area, kitchen and food hygiene is of great importance to ensure consumer health. The aim of this study was to verify the hygienic performance of commercial dishwashers with a water-change system by use of bioindicators. This test method is described in DIN SPEC 10534. Micrococcus luteuswas used as the test germ instead of Enterococcus faeciumas it imposes no pathogenic risk. Micrococcus luteuswas identified in initial studies as an appropriate test germ for hygiene studies. Cleaning and rinsing temperatures and holding time of the cleaning program were varied. High rinsing temperature with a constant cleaning temperature and high cleaning temperatures with a constant rinsing temperature led to a reduction of the viable cell count. Increasing the cleaning temperature resulted in a higher decrease of the viable cell count than increasing the rinsing temperature.

In times of low-temperature washing, laundry hygiene gains importance, as microbial contaminations on textiles can cause infection transmission and malodour formation. This study systematically investigated the antimicrobial effect of laundry detergents (solid and liquid market detergents) with regard to time and temperature in domestic washing machines. To evaluate the microbial reduction, cotton swatches contaminated with Staph. aureus, Ent. hirae, Ps. aeruginosa, C. albicansand T. mentagrophyteswere washed at 20 to 60 °C, varying the washing time, with and without detergent. All tested washing factors affected the antimicrobial effect of to a varying extend, depending on the germ. The used solid market detergent containing activated oxygen bleach provided a way to achieve high microbial reductions in low temperature washing.

Several different approaches are commonly used to obtain information about the performance of laundry systems, e.g. washing machines. The evaluation of washing performance with soiled test fabrics is commonly done by measuring the reflectance of the washed test specimen. The absolute reflectance readings may be used if the results are only compared within a series of tests using the same batches of test materials for all runs. The inevitable uncertainty of any test results may be reduced if the results can be expressed as ratios compared to the performance of well-known or well-established reference systems tested in parallel. This approach is defined in IEC 60456:2010 and followed globally for assessing the performance of washing machines. With the current evaluation method the calculation of the overall wash performance test result cannot be adjusted to adequately reflect the characteristics of different wash programmes designed for different purposes – or different machine technology and global regions. It is therefore the task of this paper to develop an evaluation method for assessing the cleaning performance of washing machines which is scientifically sound and statistically complete and more flexible in its application to different programmes and/or regions. A new cleaning evaluation method is suggested in this paper and applied to two sets of available data. The new cleaning evaluation method shows to have a number of apparent advantages over the method currently used. As a straightforward approach the stain specific evaluation ensures full usage of generated information including reference machine and batch values to allow calibrating the test result. The full statistical evaluation gives a more complete picture and allows partial results to reflect different aspects of system performance as well as weighting factors allow adjustment to specific requirements.

A literature review was executed to collect data on the resource consumption connected to domestic laundering processes. Data from literature on water and energy consumption were collected. The study focussed on Europe, as for Europe enough date could be collected for a thorough analysis. However, the limited data available for Japan and the USA were also included and discussed.

Since the washing performance of household washing machines must comply with certain limit values, like the ecodesign requirements in Europe, the method of washing performance evaluation is crucial. Today, the washing performance is defined as an overall washing performance in IEC 60456:2010, constituting an calculation of the average sum of reflectance values of five different stain monitors. As a result, the different washing characteristics of each individual stain are totally neglected. This study investigates how the washing cycle affects the individual stains, when washing temperature, washing time and load size are varied systematically. The results show individual stains contribute differently to the overall washing performance. For a proper assessment of the washing performance, the individual stains’ contributions to the overall washing performance are required to be considered. A supplement of temperature sensitive stain monitors is suggested. E.g., as tea has a crucial contribution at higher temperature, this stain should have a higher influence in washing performance assessment when good bleaching or hygiene performance is requested.

Washing machines should not only deliver good removal of stains, but also take care of the garments. Mechanical action produced by the washing machine has a twofold impact: It supports the removal of stains, but it also influences the structure of the textiles negatively and is, therefore, critical to textile care. Most washing machines are currently assessed by consumer organisations and political regulations, such as energy labelling, just for their washing properties. However, a long programme may provide a good washing performance, but might also damage the textiles more than a shorter programme. Test specimens assessing the mechanical impact are well known and published, for example, IEC PAS 62473:2007, however, they are rarely used. Reasons may be poor knowledge about their effectiveness in assessing the mechanical action and their reaction to different washing conditions, for example, load size, temperature and duration of the washing programme. It was the task of this study to verify this relationship and confirm that the thread removal fabric, as specified in IEC PAS 62473:2007, adds additional information to the assessment of a washing process. As a result of a wide variation of washing parameters, it could be shown that this test fabric is almost independent of the washing temperature, but shows a clear correlation with the load size and the length of the washing process. The thread removal specimens add valuable additional information concerning a relevant parameter of the washing process.

Lowering water temperatures in the cleaning step of a dishwashing program to 30°C leads to reduced energy consumption and decreased cleaning performances on persistently soiled dish- and cookware and of fatty soilings on hydrophobic surfaces. This study focusses on the question if the observed decline of the cleaning performance can be compensated for by aligning the formulation of the dishwashing detergent. A Design of experiments-method is used to quantify the effects of detergent components on the cleaning performance in mathematical models. The calculated models are used to adjust the amount of those components in a detergent formulation that increases the cleaning performance in low temperature electric household dishwashing. The modeled formulation has been verified in practical experiments.

To further reduce energy consumption of dishwashing programmes and still obtain satisfying cleaning results, water temperatures in the programme steps are decreased and running times are prolonged. To which extent the cleaning factor duration is able to compensate for temperature has been insufficiently researched until now. This study quantifies the effects of a pre-rinse step, of the duration and water temperatures in different dishwashing programme steps on the cleaning performance and energy consumption in mathematical models. Using those models it is shown that even a (cold) pre-rinse step increases the cleaning performance and that energy consumption is reduced by 25–28% and the cleaning performance decreases, especially on heavily soiled load items and of fatty soilings on plastic surfaces, if the water temperature in the cleaning step is lowered to 30°C.

To identify key features in the perception of consumer satisfaction of washing performance, a survey among detergent users from five European countries was run. Respondents from each country were volunteers recruited through the Internet without previous selection criteria. The size of the sample (over 4,000 participants) and the wide geographical distribution of the respondents delivered a large set of data. According to the collected answers, respondents show a significant degree of satisfaction with the detergents they use, regardless of type and country. They were only dissatisfied by tough stains and exceptional problems with their wash loads. Detergent additives are widely used but the use and type of laundry additive showed significant differences from country to country. Respondents understood the usefulness of stain removers and showed a high degree of satisfaction using them. Damages to textiles, when it occurs, are not usually associated with the quality of the detergent used but with other factors in the washing process.

Washing machines sold for private households are increasing in capacity. The aim of this study was to assess how these higher capacities are utilised by consumers. A consumer survey was conducted in eleven European countries with more than 5,000 participants who are substantially involved in washing laundry. Questions were asked about their washing machines and washing behaviour. The main outcome is that these new machines are welcomed, but it seems that the consumers are not utilising the larger capacities. This may result in higher energy and water consumption as the new machines are optimised to work most efficiently at maximum load conditions.

The proper cleaning of used dishes provides an essential means to maintain a sufficient hygiene level on food contact surfaces. However, little is known on the microbiological quality of domestic dishwashers themselves, especially in relation to consumer habits. This study investigated dishwashers in German households to analyse the number and composition of microbial colonisers and their putative impact on dishwashing hygiene. Although the microbiological status of dishwashers appeared to depend on multiple factors, data suggest that a trend towards lower temperatures might effect in a decreased hygiene.

Washing machines in Europe have to comply with regulations fixed in the Energy Label and Ecodesign legislation. They require declaration of the specific consumption and performance values which are deduced as average values from tests on three different treatments. Detailed data about the individual tests are normally not available to the public but just kept in the technical documentation of the manufacturer. Within the ATLETE II project 62 washing machines were measured to verify their compliance with the declared value. As this was an EU funded project all data are now also publicly available. This set of detailed measured data was used first to get a deeper inside into the performances and consumption values of the specific parameters and second to see how different the approaches are between manufacturers to achieve the same or similar declaration values. Additionally it could be shown that there are significant differences between those programmes used for the declaration and those offered as “normal” programmes to the consumer.

The aim of this study was to assess consumers' behavior in home hygiene with particular attention paid to hygiene in laundering. In this way, the applications of washing temperatures and detergents on textiles are evaluated. The data were obtained by using a questionnaire distributed at the “Action Day Sustainable Washing” arranged annually. The results of this sample provide a relevant insight into consumers' behavior: The consumer can generally estimate the level of infection risk coming from the different textiles. However, the majority of high risk textiles, such as cleaning cloths, are washed with detergents that do not contain any bleaching system. In view of the washing temperatures applied, the results indicate differences between the generations. This study clearly demonstrates the need for enhanced consumer communication regarding hygiene effectiveness in laundering.

Decreasing resource consumption concerning electricity, water and detergents in the framework of automatic dishwashing is not only determined by technical improvements. First and foremost, the use phase, in other words, the consumers and their choices, for example, the type of dishwasher, the kind of dishwashing programmes selected and the method of pretreating dishes, play an important role in terms of saving energy. To investigate the current dishwashing habits in Germany, 4 000 private households were asked about the usage of automatic dishwashers and the general dish treatment in everyday life. The results of the survey have shown a broad range of consumer behavior due to individual dishwashing habits. It also became obvious that consumers who more frequently use the energy saving “eco programme” tend to pretreat some dishes, such as pots and pans, with additional resources more often than the households who use other programmes. Therefore, the study reveals that a holistic view due to all resources consuming dishwashing steps is necessary to deduce adequate consumer recommendations for saving energy, water and detergents.

In the past years some researches were conducted to model laundry washing in the automatic washing machine. The most studies, however, were focused to some aspects of the automatic laundry washing (e. g. spinning cycle) and not on the washing process as whole. In this paper a model of a washing machine is presented that is based on measured data of 9 different washing machines with rated capacity between 5 kg and 11 kg, which are produced by six different manufacturers. The proposed approach is based on multiple linear regression analysis to extract the systematic, model independent behavior of washing machines and is used to calculate the consumption of the water, energy and detergent in dependence of the rated capacity, washing temperature, duration of the main wash, load size and washing performance.

In order to simulate the usage of washing machines by the consumer, a concept of a “virtual washing household” is developed that, to some extent, behaves as a real life household. As essential part of this virtual household is the virtual washing machine in which washing cycles are conducted in dependence of the washing parameters, household size and behavioral parameters. The concept stipulates that a washing cycle is conducted only when the household has enough laundry collected, so that the loading capacity of the washing machine is used, otherwise the houshold waits. Houshold, however, washes the laundry despite the loading capacity restrictions when a certain, waiting time (defined by the houshold) is elapsed. The consequences of all washing cycles during one year are calculated in terms of CO2equivalent emissions caused by the energy, water and detergent consumed for reaching a well-defined level of washing performance. This model offers a high range of possibilities to simulate some of the consumer's behavioral patterns and so helps to identify an optimal washing behavior for different sizes of washing machines.

The aim of this study was to develop a repeatable method for the measurement of microbial load reduction factors after hand and machine dishwashing processes that meet the requirements associated with consumer studies, based on non-pathogen test strains. Microorganisms were isolated from tableware, identified and cultured for this purpose, mixed with soiling agents and lyophilised for storage purposes. Detailed instructions for ambient conditions and disinfection, and preparation and application of soiling agents were defined. The method chosen in this study successfully led to repeatable results. The food matrix of the soiling agents used for the application of test strains shows to have a large impact. This is, therefore, the first repeatable method that enables the comparison of microbial load reduction factors after machine with hand dishwashing. In addition, the method was designed in a way that enables further consumer studies.