A study by the University of Leeds in the United Kingdom: When the hand dryer is used to dry hands, the bacteria on the hands are 27 times more than those on paper towels. In 20 14, Best EL, a microbiologist at the University of Leeds in the United Kingdom, found that the number of bacteria on the hands of people who use hand dryers is 27 times that of people who use paper towels.
The research team covered their hands with lactic acid bacteria. After washing their hands, they were compared with "spray-drying mobile phone", "warm-drying mobile phone" and "hand towel", and investigated air samples 120, including 60 in the experimental group and 60 in the control group.
After careful comparison, it is found that the "colony forming unit" (cfu) of jet dryer is 70.7, while that of warm air dryer is only 15.7, but toilet paper is the least, only 2.6. It is equal to that the colony of jet dryer is 27 times that of toilet paper and 6 times that of warm air dryer.
The research team believes that "the jet hand dryer will spray germs into the air and then pass them on to people who come to the toilet to wash their hands, and even promote microbial cross-contamination, at least in medical institutions, which is not suitable for using hand dryers. 」
In the study of 20 15, Best EL once again confirmed the harm of this incident. "Jet dryer can spray air 1.5 meters as far as possible, and at the same time disperse the water left in the hand into tiny water droplets, and then spread out with germs. 」
What does Dr. Taiwan Province think: I always spray alcohol after washing my hands in the hospital! "Doing is really important. Of the five steps of washing hands, the last step is wiping. Wu Changteng, an emergency pediatrician at Linkou Chang Gung Hospital, said that after washing your hands, there will still be some germs on your hands, and through the action of "wiping", the remaining germs can be wiped clean, and washing your hands is truly thorough.
No, many people left without waiting for "complete blow drying". Instead, they spray more bacteria on their hands. In addition, the temperature and humidity of the hand dryer are suitable for the survival of germs. Wet hands bring germs near the hand dryer, making the hand dryer a "new home" for these germs.
Wu Changteng said that German studies have found that coronavirus can survive on the surface of objects for 9 days. "But generally speaking, germs can survive for at least 5 days, so it is really recommended not to use hand dryers. 」
So the best way to wash your hands is to dry them with toilet paper, not with a hand dryer. However, toilet paper is not everywhere. Wu Changteng believes that it can be directly wiped with ordinary toilet paper. In fact, most germs can be reduced by wiping. But if he thinks it can't be wiped off, his usual practice in the hospital is to "spray alcohol".
"Alcohol will dry directly. After waiting for 15 seconds, the bacteria will also be killed, which can meet two needs. Wu Changteng said, "It was the same when I was in the hospital. 」
Steps to wash hands of pediatric emergency physician Wu Changteng.
Get your hands wet. Wash your hands with soap for 20~30 seconds according to the method of "holding your bow inside and outside and standing your wrist". Wash your hands. Dry your hands, then spray alcohol, and wait 15 seconds to dry naturally.