Air Dryers and Poorly Washed Hands Are a Bad Combination

High speed air dryers commonly found in public restrooms can leave contaminants on poorly washed hands, which are then spread to clothing and other surfaces, according to a study published yesterday in the journal of the Society for Healthcare Epidemiology of America.

Researchers in the United Kingdom examined various hand drying methods to determine the impact of hand hygiene on the spread of germs. Study volunteers dipped their hands in a nonharmful viral solution, shook them off without washing, then dried their hands using either an air dryer or paper towels. During the experiment, participants wore an apron to test contamination on their clothing. They then took a predetermined path through a hospital touching commonly used surfaces, such as elevator buttons, along the way. Researchers collected samples from each surface the volunteers touched.

On average, the levels of contamination found on surfaces was 10 times higher after the volunteers dried their hands with an air dryer compared to after drying their hands with a paper towel. Researchers also noted greater microbial transfer to the apron when volunteers used the air dryer.

“The study was performed in a health care setting and has important lessons for health institutions that still have high speed air dryers in restrooms,” said one of the study authors, Ines Moura, PhD, a research fellow at the University of Leeds in West Yorkshire, England. “But the results are also relevant for public restrooms with high foot traffic.”