Hand hygiene: surfaces
Posted on 31 May 2016
Keyboards, elevator buttons and door handles are some of the dirtiest surfaces you’ll encounter. But how long do germs really live on these surfaces?
You step into an elevator and press the button for your floor. You open a door, using a door handle. You sit down in front of computer and start typing. Not once do you stop to think how many other people have touched that button, that door handle or that computer keyboard. And not once do you stop to think about whether any of those people were carrying germs or microbes on their hands… And that’s OK, because really: germs don’t survive for very long when they’re out in the open, do they?
Unfortunately, the answer to that question is: they do. In some cases. Various factors come into play, like humidity and the type of surface. Any surface that has nutrients (like food particles, skin cells, blood or mucus) will provide a happy home for microbes – which is why your hands and your kitchen sponge make for such a fertile germ breeding ground.
Viruses, generally speaking, survive for longer on non-porous surfaces (like stainless steel and plastics) than on porous surfaces (fabrics, tissues, etc). Cold viruses have been shown to survive on those surfaces for a few days, but their ability to cause an infection reduces quite quickly, and most don’t survive for longer than 24 hours. A handful of viruses only last for a few minutes, but about half of rhinoviruses (which cause common cold) can still be infectious on hands after about an hour. Most infectious flu viruses, meanwhile, can survive on hard surfaces for about a day, and on tissues for only about 15 minutes.
Of course, you can’t go around wiping down or cleaning off every door handle and elevator button that you come into contact with… But you can protect yourself by washing your hands regularly. Nursing professional Christine Smedley, infection prevention and control coordinator at Mediclinic Southern Africa, talks us through the correct way of doing that.
First, wet your hands with clean, running water (warm or cold), then turn off the tap and apply soap. ‘Hot water may contribute to dermatitis, which prevents effective hand hygiene being performed,’ Christine warns.
Then, lather the soap on your hands by rubbing them together. ‘Be sure to rub the backs of your hands, between fingers your and palms, as well as interlocking your fingers to rub your nails,’ she says. Then scrub your hands for at least 20 seconds. ‘Hand washing should take about 40 to 60 seconds,’ says Christine. ‘So hum the “Happy Birthday” song from beginning to end twice.’
Finally, rinse your hands well under clean, running water, and then dry them using a clean towel or disposable paper towel. And try to not think too much about those elevator buttons and door handles.