Study: Mayo Clinic Compares Paper Towels, Other Hand Drying Methods

Many people don’t realize that drying is the final step of the hand washing process. Not only does it remove the water from hands, but it also removes bacteria. If Americans aren’t washing their hands properly, it becomes paramount that they dry them using the best possible means.

In August 2012, the Mayo Clinic released an extensive literature review, which looked at 12 studies comparing hand drying methods over the past 40 years to investigate the best drying techniques.

The goal was to analyze the available research regarding the hygienic values of different drying methods, including drying efficiency, the effective removal of bacteria, and the prevention of cross-contamination, among other factors. While paper towels were a primary source for the research, the study also compared the drying attributes of cloth towels, hot air dryers and jet air dryers.  

The study had its limitations, however, due to the influx of conflicting and opposing information. The writers admit that there “appears to be little agreement regarding the most hygienic method of hand drying.”

While some studies place paper towels above hand dryers, others did the opposite. A few studies noted that much of hand dryer’s inferiority may be due to the “degree of wetness,” drying time and the chosen protocols used to measure efficacy.

The Mayo Clinic found that single-serve cloth towels provided the fastest drying times, absorbing roughly 96 percent of water from hands in about 10 seconds. Paper towels soaked up residual water within about 15 seconds, while jet air dryers showed similar drying rates. Conventional electric air dryers took an average of 45 seconds to dry hands.

The time required for each drying method doesn’t influence how much time restroom visitors are willing to wait for their hands to dry, however. The study notes that men spent an average of 3.5 seconds on cloth towels, and only about 17 seconds under hot air dryers — well below half the time actually needed to thoroughly dry hands.

Women spent more time drying their hands with cloth towels, but even less time under hot air dryers, at approximately 13 seconds, which resulted in hands that were only 68 percent dry.

Fast drying times are exactly why consumers prefer paper towels, says Jason Jones, vice president of sales at Cavalier Inc., in Norfolk, Va.

“They still have wet hands [with hand dryers],” Jones says. “There’s dirty water that they are blowing off their hands onto the floors. Then they’re touching the door handles.”

Cavalier President, Bruce Heller, says it doesn’t take “rocket science,” to see the effective drying properties of paper towels. Besides paper towels’ ease of use, he says, air dryers cause more inconveniences than benefits — including the pool of “dirty water” that collects beneath the devices.

While manufacturers may be able to remedy the mess with mats similar to those placed underneath urinal systems, Heller says that won’t solve dryers’ slow drying times.

“With hand dryers, people are still walking away with wet hands, doing a funny dance,” trying to air dry their hands, he says. “Seems to me that the patrons and customers want the paper towels.”