The ad, which was created in-house and aired in May 2017, attracted three complaints from members of the public, who challenged whether the claims it made were misleading and could be substantiated.
The spot opened with a shot of a woman at the window of her house, looking concerned, and another shot of a car exhaust pipe producing green vapour as the voiceover began: "What could be worse than the pollution indoors?".
The voiceover continued: "Well, the pollution indoors can be up to five times worse where gases and microscopic particles can build up". Then the camera follows the woman as she walked into the kitchen where a number of appliances let off purple and green vapour.
The woman was then shown holding a smartphone, on which an app stated the word "Poor" in reference to the air quality in her home. The camera then cut to a shot of the Dyson Purifier Heater, an air filtration device, which sucked in the coloured vapour.
The complainants questioned whether the ad exaggerated the health risks posed by pollutants in a typical domestic kitchen. Dyson told the ASA that neither the ad’s voiceover nor its visuals mentioned health risks and also offered to remove the shot of the car’s exhaust fumes from the ad.
On the claim that pollution indoors "can be up to five times worse" than outdoors, Dyson referenced studies from the European Respiratory Journal, the US Environmental Protection Agency, the Royal College of Physicians and US research institute SRI International.
However, the ASA disagreed with Dyson regarding health claims. It felt consumers would interpret the ad as telling them that indoor pollutants were more "damaging" than outdoor pollutants due to the comparison with exhaust fumes which they already know to be damaging to health, the look of concern on the woman’s face, the use of the word "worse" in the voiceover, and the word "poor" on the phone screen.
The studies submitted by Dyson did not state whether indoor pollutants were actually more damaging to health than outdoor pollutants, the ASA concluded.
The advertising watchdog ruled the ad breached the BCAP code on misleading advertising and on substantiation and told Dyson it must not run again in its current form.
A Dyson spokesperson told Campaign: "Indoor air quality can be up to five times worse than outdoor. We respect the ASA’s decision and will refine our advert but will continue to raise awareness of this issue."