After a long year of pandemic, we have learned the basics of good hygiene. Washing hands with soap and water while doing vigorous movements has become essential, along with the application of hydroalcoholic gel.
If we really want to clean our hands of bacteria and viruses, we must wash our hands vigorously for at least 20 seconds each time. At least that’s what arecent study by South Cambridgeshire reveals.
Wash your hands vigorously to remove the virus
A two-dimensional model has been created that captures the key mechanics of hand washing. It reveals that the effectiveness of hand washing is related to the force with which it is rubbed, but that the process still takes time even when done correctly.
A good technique to make sure we are washing our hands long enough is to sing ” Happy Birthday ” twice in a row. Handwashing has long been established as an effective way to combat the spread of disease and infection, although the underlying physics had rarely been studied.
Remember that it is necessary to clean our hands after going to the bathroom or changing a diaper, before and after handling raw food, before eating or handling food, after blowing the nose, sneezing or coughing, before and after treating wounds and after touching animals, including pets, their food, and their cages.
Proper hand washing removes dirt, viruses, and bacteria to prevent them from spreading to other people and objects. During the COVID-19 pandemic, it is also essential to wash your hands before touching your face or mask, when entering and leaving a public place, or when touching an item or surface that other people may touch frequently.
Perform quick movements for 20 seconds
The study looked at hands on a microscopic scale, showing skin roughness as a pair of wavy surfaces, separated by a thin film of liquid, moving side by side when scrubbing.
Particles like bacteria and viruses end up trapped in the valleys of these surfaces, trapped in what the researcher calls potential wells . Given this, in order for particles like bacteria and viruses to be dislodged from a hand during washing, the energy of the water flow must be high to move up and out of valleys. The model revealed that the strength of this flow depends on the speed at which you rub your hands.
Specifically, more vigorous movements remove particles more easily. When it comes to making sure hands are clean, researchers reveal that the process is a lot like cleaning a stain on a shirt. The faster the movement, the more likely viruses and bacteria will be successfully killed.
“If you move s hands too softly and slowly, with each other, the forces created by the fluid flowing are not large enough to overcome the force holding down the particle , ” said Dr. Hammond.
However, even when rubbed vigorously, the particles are not removed quickly, and the study indicates that 20 seconds of action are needed to remove all potential bacteria and viruses. Knowing the physical mechanism that removes particles from dirty hands can help researchers formulate more effective and environmentally friendly soaps in the future.
