Many people today are worried about the question, which masks better protect against coronavirus? This issue was relevant even before the introduction of the general mask regime.
It is further complicated by the fact that the initial shortage of masks and their high cost led to the widespread use of homemade and alternative masks.
Which masks protect better
It is assumed that wearing protective masks significantly reduces the distance over which viral particles are exhaled. But many of the remedies used have not been tested in practice. This means that we can only speculatively judge their effectiveness.
A study by scientists from Duke University in the United States, published in the scientific journal of the American Association for the Advancement of Science, is intended to correct the situation.
Emma Fischer and her colleagues have come up with a quick and inexpensive way to assess the protection of 14 types of masks. To do this, they only needed a cardboard box, electrical tape, an optical laser and a lens.
The design of the experiment is simple: the operator puts on a mask and speaks in the direction of an expanded laser beam inside a dark room. The droplets pass through the laser beam and scatter the light, which is recorded by the mobile phone camera.
Scientists at Aalto University using a supercomputer showed how coronavirus particles spread when coughing or talking, as well as how long they are in the air 🦠
🤧 Experts have simulated a situation in which a person sneezes or coughs in a grocery store. pic.twitter.com/VDzKX7OKzc
– Moscow 24 (@ infomoscow24) April 11, 2020
«We have confirmed that small droplets are thrown out when people speak. So the disease can spread by talking, without coughing and sneezing.”Says Fischer. – We also saw that some face masks are better than others at blocking particle release.».
Mask effectiveness rating
- The first place, as expected, was taken by the N95 respirator mask without valves, which allowed less than 0.1% of microdroplets to pass through.
However, its version with valves did not make the top of the best. Fischer emphasized that such masks provide excellent protection for the wearer, but the strong flow of air from the valve when exhaling is dangerous to others.
- The second place was taken by disposable medical masks.
- Third, multi-layer masks made of cotton, which many make on their own, let only 8% of micro-droplets pass through.
- Many homemade masks vary widely in effectiveness. Which is not surprising, given the differences in their materials and manufacturing methods.
- Bandanas and knitted masks are practically useless, as they allow up to 50% of particles to pass through.
- The saddest situation is with the BUFF® multipurpose bandages, which resemble a fabric tube and are loved by athletes and tourists.
On the contrary, such means of protection increase the risk of infection (105%). “In the case of a fleece collar, the number of drops is even more than when a person does not have a mask.”, – the authors of the study say.
This is due to the fact that such material breaks down large droplets into smaller ones, which can remain in the air for a long time and are potentially more dangerous. It would seem that some kind of mask is better than none at all. But it turns out that there are exceptions to this rule.
Do not forget that a medical mask is only one of the protective measures. This is not a panacea or 100% protection. But wearing a mask definitely reduces viral load and becomes a barrier to direct contact with patients. Disinfect your hands regularly, ventilate your home and wear a quality mask to protect yourself and your loved ones from possible infection.
Source : takprosto.cc