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When It Comes to Hand Washing, Drying Matters, Too

Some people sing the ABC song, some sing Happy Birthday. Personally, I go for “Summertime, and the living is easy…”

These days, we’re all aware of the 20-second rule for proper hand scrubbing, however we measure it. We dutifully work up a lather, rub front and back, don’t miss the fingertips, and get between our fingers.

Our intentions are golden, but about the 50^th hand wash of the day, we are apt to abbreviate the procedure. Perfection becomes approximation.

And then you dry your hands.  This is an important step that has not received enough attention. Whether it’s covid-19 or regular flu, good drying is good practice. That’s because, when you thoroughly dry your hands on a towel after washing well, you remove most germs. But if you only shake your hands dry, you leave millions of bacteria and virus germs in place, ready to spread around.

For years, we’ve all been exposed to jet air dryers in public restrooms that claim to lower the risk of contamination from paper towel litter. It sounds logical. With the dryer system, there’s never any paper towel litter hanging around, no need to touch a dispenser that goodness knows who touched before you.

It’s wrong, though. Recent tests that researchers in the UK published found that “when people use a jet-air dryer, the microbes get blown off and spread around.”  If someone washes his hands badly or incompletely, jet dryers fill the air with even more germs. It turns out that those germs may even go beyond the restroom itself.

Several studies have confirmed the superiority of paper towels versus air dryers in public places. But what is best at home? Our choices are usually cloth versus paper.

Scientists have studied this question, too. Here’s what a survey of 12 studies concluded about paper, cloth, and air:

Cloth towels tend to be more effective at removing all water. Single-serve cloth towels would be best at drying hands.

Hot air dryers are the worst. They take 45 seconds to do what a paper towel can do in 10 seconds. But research also reveals that we don’t spend a lot of time drying our hands. When using a towel, men spend 3.5 seconds drying; women spend 5.2 seconds. When using an air dryer both men and women only spent about a third of the time needed to do the job well.

So, just as an aside, when you are confronted with a hot air dryer, there are two things to remember. First, it takes a long time. But the second thing is counterintuitive—don’t rub your hands.  Rubbing hands inhibits the dryer’s efficiency at removing bacteria from your skin.

At home, you can choose cloth or paper. Both work well at completing the job of removing germs left after washing.  It’s the effect of friction that gently “scrapes” the germs off your skin that makes towels so good at their job.

As for paper versus cloth, the choice is yours. Naturally, the most sanitary system is a single-use towel. Which for most of us means paper.

If you have the luxury of owning a huge stack of one-time cloth towels, however, you will not only get well-dried hands, you can save the environment from tons of paper waste, too.

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