| Year | Finding |
|---|---|
| 2008 | University of Westminster study: paper towels cut bacteria on hands by up to 77%, while warm-air dryers increased it by 254%; jet dryers could blow microorganisms up to two metres |
| 2014 | Published research found high-speed dryers spread bacteria through the air |
| 2020 | A study found hand dryers and paper towels equally hygienic, a result that remains disputed |
Hand dryers produce over 80 decibels at 3 metres, and a 2020 study measured Dyson models among the loudest at up to 121 dBA, raising concerns for children's hearing.