Ad description

An ad for a Bosch dishwasher on the BSH Home Appliances website,, was headed "Our most environmentally friendly dishwasher". Further text stated "Bosch ActiveWater dishwashers ... use even less water than ever - only 6.5 litres*. With water consumption at an all time high, it is more important than ever to choose a dishwasher that helps preserve our most precious resource. *6.5L water consumption in the Economy 50°C programme". Under the heading "Less Water", text stated "Our new AquaStar dishwasher uses only 6.5 litres* of water to wash 13 place settings on a standard Eco 50°C programme - every time. This compares to a staggering 49 litres of water if you washed-up the same load by hand".


The complainant challenged whether the claim that washing up by hand used 49 litres of water, in comparison to a full load in the Bosch dishwasher, was misleading and could be substantiated.


BSH Home Appliances Ltd (BSH) did not agree that the claim was misleading. They based the claims on the findings of a study carried out in 2009 on the manual dishwashing habits of UK consumers. They provided the study and said that consumer tests were carried out under uniform conditions close to a standard test method in relation to both manual and automatic dishwashing. The study concluded that on average participants used 49.2 litres of water to wash the dishes used in the study.



The ASA considered the study provided by BSH. We noted the amount of water used to wash up by hand depended on the efficiency of the washing up techniques used. The study had 150 participants who were recruited to be representative of the UK population. They were given 12 place settings of tableware to wash up in a lab setting, and were asked to do so in accordance with their home washing habits. There was a high level of variation in the amount of water and techniques used, such as pre-soaking dishes, re-using water, rinsing dishes after washing or having the tap running. Water usage varied from 14 litres to 206 litres, with 49 litres the mean amount of water used. We were concerned that the issue of whether participants might be more careful regarding the amount of water used when washing up in their own homes was not addressed in the study, and that the wide variation in results meant that the average figure of 49 litres was unlikely to be representative of the amount of water that would be used in a domestic setting by consumers.

The participants had been asked to wash 12 place settings. The participants who owned dishwashers had also been asked to load the dishwasher until they considered it was full. Only 33% had been able to fit all the 12 place settings into the dishwasher, and the remainder left out between one and 20 items. This meant that the number of dishes being washed by hand was greater than most people were able to fit into a dishwasher, and so meant the water usage comparison was unfair. The study also did not mention whether people usually rinsed dishes before putting them in the dishwasher. We understood this was a common practice and considered it should have been taken into account when comparing water usage.

The ad stated "This compares to a staggering 49 litres of water if you washed-up the same load by hand" which we considered was an absolute claim that washing up the same load by hand would normally use 49 litres. Because the evidence supplied by BSH was not sufficiently robust we concluded that the claim was misleading.

The ad breached CAP Code (Edition 12) rules  3.1 3.1 Marketing communications must not materially mislead or be likely to do so.  (Misleading advertising),  3.7 3.7 Before distributing or submitting a marketing communication for publication, marketers must hold documentary evidence to prove claims that consumers are likely to regard as objective and that are capable of objective substantiation. The ASA may regard claims as misleading in the absence of adequate substantiation.  (Substantiation) and  11.3 11.3 Absolute claims must be supported by a high level of substantiation. Comparative claims such as "greener" or "friendlier" can be justified, for example, if the advertised product provides a total environmental benefit over that of the marketer's previous product or competitor products and the basis of the comparison is clear.  (Environmental claims).


The ad must not appear again in its current form. We told BSH not to make claims regarding comparative water usage unless they held sufficiently robust evidence.

CAP Code (Edition 12)

11.3     3.1     3.7    

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