The claim: Paper towels thwart more germs than air dryers.
The facts: The key to clean hands is simple. Wash thoroughly with soap and water. However, once you have turned off the tap, do you reach for the paper towel or the air dryer?
Bacteria thrive on wet hands, so the method that removes the most moisture should theoretically be the most effective.
But some studies suggest that other factors play a role. A few have portrayed conventional air dryers - and the newer jet-air machines where users stick their hands into a slot while air shoots out rapidly - as bacterial breeding grounds that contaminate hands and disperse germs.
However, these studies tend to have a conflict of interest: financing from the paper industry.
In 2000, the Mayo Clinic conducted an independent study. Researchers recruited 100 people, contaminated their hands and then instructed them to wash with soap and water. Then they had to place their hands under a warm air dryer for a single 30-second cycle, or use a cloth or paper towel for 15 seconds.
In the end, the scientist called it a draw: both methods dried the hands thoroughly and produced equivalent reductions in bacteria counts.
Other studies that looked at alcohol hand santisers found that they eliminated the most bacteria but not all viruses, including the norovirus - which causes acute gastroenteritis to humans. To be effective, they must be at leas 60 per cent alcohol.
The bottom line: The best available evidence suggests that as far as germs go, the method of drying is less important than the amount of time invested. What is important is that you take the time to dry your hands thoroughly.
- The New York Times