According to the Applied and Environmental Microbiology journal, they found that the air being blasted from hand dryer’s contains fecal bacteria.
Scientists sampled 36 bathrooms at the Farmington campus.
In the study, they compared normal bathroom air to the air being blasted from hand dryer nozzles. The air coming from hand dryers contained significantly more bacterial colonies than the other sample.
All the restrooms on the campus with hand dryers, had up to 254 bacterial pathogens, all stemming from feces.
Author of the study, Peter Setlow, told Newsweek that, “Bacteria in bathrooms will come from feces, which can be aerosolized a bit when toilets, especially lidless toilets, are flushed,”
Researchers suggest installing high-efficiency particulate air (HEPA) filters to hand dryer nozzles. While this sounds good in theory, HEPA filters only block about 75 percent of bacteria, according to the study.
These findings led researchers to conclude that hand dryers might in fact be a mechanism for spreading infectious bacteria. This is especially the case in larger buildings as people can transfer the bacteria from room to room.