What kind of face masks can filter out viruses exactly?

1 What is the difference between medical masks and non-medical protective masks?

Due to the peculiarities of the medical environment, when medical personnel operates on patients, it is necessary to prevent bacteria from infecting the patient and also to prevent the spilling of bodily fluids from the patient. Medical masks need to meet the following three conditions, filter bacteria, prevent blood spatter, and cannot have a breathing valve. These three conditions are not directly related to antiviral.

2 Why can anti-particle masks be used to antiviral? Is it mandatory to use a medical mask for protection 2019-nCoV?

It must be understood that viruses cannot exist in air species alone and that pathogenic microorganisms in the air (such as pathogens or viruses) are also particulate matter, which can be filtered by particulate matter filter material. Studies have shown that particles of 0.3um diameter are the most difficult to capture, so particulate matter filtration tests are all about selecting particles of 0.3um diameter.

If protection from bodily fluids or blood splashes is not required, just protection from the presence of influenza virus, infectious droplets, or other harmful particulate matter in the air, the use of non-medical protective masks is sufficient.

3 Medical masks have no particulate matter filtration efficiency, how do they antiviral?

In contrast to non-medical protective masks, medical masks do not specify particulate filtration, e.g. medical standard YY/T 0969, EN 14683, ASTM F2100, but these standards have been shown to be effective against viruses because bacteria are also particulates. If it can filter out bacteria and therefore particulates, but the exact relationship between them has yet to be demonstrated.

4 Can a breath valve antiviral?

For the 2019-nCoV, a face mask with a respiratory valve is not to be worn. The reason for this is that while wearing a filtered mask with a breath valve can prevent others from infecting us, but we can’t be sure we’re not infected, and antiviral face masks that don’t use a breath valve are meant to prevent us from infecting others.

5 Filtration does not kill the virus

The purpose of the antiviral face mask is to filter out the tiny particles of air that may be attached to the virus; filtering is not the same as killing. The antiviral face mask simply keeps the virus out, preventing it from getting inside, and the surface of the antiviral face mask can still hold the virus. Therefore, try not to touch the outer layer of the mouthpiece with your hands, and if you do, you need to wash your hands.

6 How to choose an antiviral face mask?

If it’s just to antiviral, choose a face mask that can filter the particles. The 9 standard masks given in this paper can effectively antiviral virus. But remember that you shouldn’t choose ordinary cotton masks or privacy protection masks worn by movie stars or sport starts. These masks are mainly for beauty and can’t effectively antiviral.