The body of evidence continues to grow: masks protect the person wearing them from COVID-19, in addition to those around them. But with so many choices, what's your best option?To get more news about medical mask stock, you can visit tnkme.com official website.

Regardless of mask-type, fewer coronavirus particles get through to people wearing face coverings, according to a new paper that will be published in the Journal of General Internal Medicine shortly. Fewer particles could result in milder infections if the virus manages to slip through.

Another study, published last month, compared the COVID-19 growth rate before and after mask mandates in 15 states and the District of Columbia. It found that mask mandates coincided with slowdowns in daily COVID-19 growth rates. While working on another recently published study, researchers from Duke University evaluated the effectiveness of 14 different types of masks by estimating how many droplets traveled through the mask during normal speech.

The researchers used a laser beam, a lens that turned a laser beam into a sheet of light, and a mirror that directed light into a dark box made of cardboard. People spoke the same phrase into the box with, and without a mask. The particles that hit the lens produced visible flashes recorded by a phone’s camera on the other end of the box.
So what's the most effective kind of mask against COVID-19?
The solid dots represent results of 10 trials for a mask by one speaker. The hollow circles represent the relative droplet counts for four speakers.Medical N95 mask with no exhalation valve proved to be the most effective. However, the CDC asks the general public to not wear N95 respirators, which are limited in supply, so they can be reserved for health care workers and first responders.

2. Three-layer surgical mask
When study participants said the phrase "stay healthy, people" wearing a three-layer surgical mask, only a tiny fraction of droplets got through.

Surgical masks are single-use only and are made to protect the wearer's nose and mouth from contact with droplets, splashes and sprays that may contain germs. They also filter out large particles in the air.
3. Cotton-polypropylene-cotton mask
A mask made from two layers of cotton and one layer of synthetic material proved to be the most protective option aside from masks intended for medical professionals. Another recent study suggested that a homemade cloth face masks likely need two or three layers to be effective in preventing the spread of the coronavirus.

A single-layer covering reduced the droplet spread from speaking, while the double-layer covering was better in reducing droplets from coughing and sneezing, according to the researchers. 
4. Polypropylene apron mask
This mask had two layers of polypropylene, a soft easy-to-clean synthetic fabric. Polypropylene is one of the most popular materials for masks because viruses and bacteria can't live on the fabric for long.

According to a study published in Nano Letters, polypropylene may be one of the best materials for a homemade mask. It has the electrostatic charge that traps incoming and outgoing particles. It loses its electrostatic charge when washed, but can be recharged by rubbing it with a plastic glove.
5. Swath
Researchers used a slightly damp washcloth in another experiment. Using high-speed video, they found that saying a simple phrase generated hundreds of droplets ranging from 20 to 500 micrometers. The washcloth blocked nearly all those droplets from the person's mouth.

6 - 7. Two-layer pleated style masks
When choosing the material, make sure the cotton is woven at a high density so there are no visible pores under light, according to the study in Nano Letters. If that's not the case, it may be best to use multiple layers.

"I wouldn't put too much stock in the small differences that we saw between the different cotton masks; I would emphasize that fit is important," Warren said.