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What’s the best way to hold my hands under a hot air blower to dry them efficiently: flat or cupped? Or something else?
Chris Daniel
Colwyn Bay, Conwy, UK
During the covid-19 pandemic, lots of us had to relearn the correct technique for washing your hands: scrub for at least 20 seconds using clean, running water and soap, then rinse and dry them thoroughly. This last part is as as the first. Damp or wet hands can promote the growth of bacteria and make it easier for them to spread onto other surfaces, risking cross-contamination.
Older types of electric hand dryers rely on the heat of a low-speed airstream to dry hands by evaporation. However, this method can take about 45 seconds, so users often abandon the process before their hands are completely dry, shaking excess water off or wiping their hands on their clothing, which can increase the . Another common action is to rub the hands together to spread the remaining water more thinly over the skin to hasten drying, but this has been to result in more bacteria being left on the hands compared with keeping the hands still.
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There are pros and cons to all methods, but the message is clear: fully dry hands are healthier and safer than wet ones
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High-speed electric dryers emit round or bladed jets of air that per second and can blow water from the hands in . But these machines have been found to spread bacteria into the air and onto the user’s clothing, as well as surfaces up to 2 m away.
The technique recommended by the manufacturers of the bladed-air style of dryer is to position the hands in the air flow with the fingers extended, starting at the wrist and drawing the hands backwards to allow the water to be blown off towards the fingertips and away from the body. This process is repeated for both sides of the hands until they are dry. For dryers with round jets of air, the technique is similar, but with the hands moving in a circular pattern so that all areas are dried.
It is tempting to try to speed up the process by cupping your hands under the high-speed air flow, but this may simply have the effect of blowing excess water back into your face and into the room while not producing any benefit.
There are pros and cons to all drying methods, but the message is clear: fully dry hands are healthier and safer than wet ones.
Hillary Shaw
Newport, Shropshire, UK
“Something else” might be best for the planet. If it isn’t cold outside and you aren’t doing anything that needs dry hands, a quick shake and they will soon dry via evaporation. A hot air dryer may of carbon dioxide emissions annually. Admittedly, this is better than paper towel use, but it is still equivalent to about a week of average CO2 emissions per person globally (4.8 tonnes). Every hot air dryer we can eliminate saves almost the same CO2 a year as is released by driving the average car 1000 km. These are small contributions, but every little helps.
Pat French
Longdon Upon Tern, Shropshire, UK
Definitely “something else”. The quickest approach to using a hand dryer is to continue the movements of the washing routine recommended to combat covid-19. This way, every part of the surface of each hand is rubbed against the other.
Rubbing the hands together under the air flow smears any gathered moisture to as thin a layer as is practically possible, so that the remainder evaporates quickly. This standard routine ensures that all parts of the hands, including between the fingers, are dried to the same extent.
This constant movement also gives the person the best chance of keeping their hands under the minuscule point at which a sensor switches on the dryer. By eliminating frustration as the machine switches off prematurely, perseverance is encouraged.
It is unlikely any technique will remove the need for a final wipe on the seat of the trousers or skirt.
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