Asked by: John Blanning, by email
Ordinary soap and water washes your hands by removing surface dirt, oil and loose skin. Studies have shown that washing your hands and drying them on a paper towel reduces the bacterial count by between 24 and 77 per cent. But if you dry your hands with a warm-air dryer instead, you can actually increase the bacteria. This is a combination of bacteria not being rubbed off your hands properly and new ones getting blown on.
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