Public Hand Dryers May Be Counterproductive, Study Says

Did you know that some hand dryers can make our hands dirty again after washing? Read today's article and learn more about what the research says about them.
Public Hand Dryers May Be Counterproductive, Study Says

Last update: 19 April, 2021

Public hand dryers are electrical devices that we find in the bathrooms of health institutions, educational institutions, shopping centers, or other spaces where many people circulate.

As the name implies, we use them to dry our hands once we’ve finished washing them. The reason behind their existence has to do with two principles: Economy and ecology. In the long run, they’re cheaper than hand towels and their manufacturing doesn’t require the cutting down of any trees.

In basic terms, public hand dryers expel hot air that comes from the same space where they’re located, making it circulate. It could be said that they recycle and heat the air inside the bathroom.

It’s this mode of operation that has raised the question of whether or not they’re safe. Evidence found in recent studies has called public hand dryers into question, as they could be contaminating hands that have already been washed.

Hand disinfection

Ever since we were children, we’ve heard adults recommend that we wash our hands repeatedly throughout the day. Before eating, after going to the bathroom, after doing manual labor, and after coming in from outdoors, etc. We now make the same recommendation to our children.

In these and other circumstances, washing is something we do to avoid contracting diseases, from the common cold to hepatitis and diarrhea.

These health conditions are often caused by viruses and bacteria that are on the hands and can come into contact with mucous membranes. Some are harmless, but other microorganisms become dangerous. And something as simple as washing hands properly is a preventive hygiene measure that we must observe.

In doing so, not only do we avoid getting sick ourselves, but we also reduce the chances of spreading infections. This is crucial for food handlers and health care personnel.

A woman rinsing her hands under the faucet.
Hand washing is effective in controlling microorganisms. It reduces the risk of getting sick considerably.

Continue reading: The Habits You Should Instill in Your Children

What do studies say about public hand dryers?

Some time ago, public offices, private companies, educational and health institutions decided to eliminate paper towels in public restrooms. This is because paper products produce waste and affect the environment.

As a result, they decided to replace the towels with public hand dryers. But it seems that this solution has turned out to be worse than the problem. What we achieve by washing our hands may become undone by the use of the dryer.

A recent study tested hand dryers in both men’s and women’s restrooms in a health care facility. This took place to detect bacteria using plates that were exposed to the dryer for a period of time.

The results of the research indicated that there are many types of bacteria, including potential pathogens and spores, which can land on people’s hands when they use the dryers in public restrooms.

That is, after washing our hands, we re-contaminate them with the hot air, which may even contain fecal bacteria.

According to the research, placing air filters in the dryers decreased the concentration of bacteria. This led to the conclusion that the bacteria are present in the air of the bathrooms. The findings point to the fact that, when flushing the toilet, a certain amount of microbes pass into the air.

Several similar studies have confirmed such findings, showing that public hand dryers can be a source of bacterial contamination. Another study even compared different hand drying methods and concluded that bacterial counts were higher for the air dryer in contrast to the paper towel.

However, not everyone agrees. Some other studies claim that there’s inconclusive evidence, as the data lacks key variables necessary to assess true infection risks. Some research even states that the risk of using public hand dryers is no higher than that of using paper towels.

Possible risks when using hand dryers

It’s worth noting that some of the microbes found in bathroom air may not cause illness or affect healthy people. However, among them, there are also more harmful microbes, such as Staphylococcus aureus.

Also, the presence of Acinetobacter has been detected, which can cause infections in people with weakened immune systems or hospitalized patients. And this is delicate, especially when it comes to hand dryers in hospital bathrooms, which medical personnel use.

Finally, beyond those that are present in the air of the restroom, germs on people’s hands are also spread by the effect of the hot air from the dryer, which works like an aerosol.

How can we dry our hands?

You may be wondering whether it would be best not to dry your hands at all. This isn’t the right choice. According to research, bacteria are more likely to be transmitted when the skin is damp.

The first and best option would be to dry your hands with a clean towel. Of course, you can do this if you’re at home or in the workspace, where you have privacy.

And even in this context, towels should be washed regularly. In case there are people sick people in your home, then you’re better off using paper towels for as long as the problem persists.

As for public restrooms, based on the results observed in most studies, the suggestion is to use paper towels to dry hands. Paper towels absorb moisture better and help eliminate bacteria that remain after washing, reducing contamination levels.

A pile of folded towels instead of hand dryers
Cloth towels and paper towels, if they’re to be used for hand drying, should be properly laundered.

How to prevent the use of public hand dryers

Bacteria deposited by hand dryers aren’t a direct cause of illness. In fact, for those with a healthy immune system, it shouldn’t be a problem.

There’s no doubt that they’re a potential risk for sick or immunocompromised people. And let’s remember that we don’t live alone in the world. On the contrary, we’re always in contact with others.

Now, the best thing to do is to dry our hands with our own towel, as long as it’s clean. However, when we go out and need to go to a public restroom, we’ll find ourselves in a dilemma.

If there are paper towels, no problem. But if there are only public hand dryers, the option is to always have a small box of paper towels for personal use in a bag or the car. This way, you’ll prevent any risks.

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