Did You Choose the Right Non-Woven Mask?

According to information from experts and WHO, wearing masks and washing hands frequently is one of the most important protective measures for the public.

Why are medical staff wearing masks also infected?

This is because severe pneumonia or general anesthesia surgery requires intubation, and tracheal intubation produces aerosols, and aerosols are the most infectious, and can reach several times or even tens of times of droplets. Coronavirus is usually spread by droplets, and many patients who would not have been transmitted to others. The aerosol generated during intubation is contagious, which is one of the reasons why medical staff account for 1/3 of the total number of cases during SARS.

Therefore, medical staff working on the front line of the epidemic must wear isolation suits. There are many kinds of masks on the market, what kind of masks should I choose?

Common masks are as follows: ordinary cotton masks, disposable masks (such as: medical surgical masks, general medical masks), medical protective masks (KN95 mask).

Among them, medical protective masks (N95/KN95 masks) and medical surgical masks are medical products that have obtained national standard management after SARS in 2003, and have the function of blocking the passage of liquid and droplet particles. If worn correctly, it can effectively prevent diseases transmitted by droplets, which is our first choice for masks. They are usually made of multiple layers of nonwoven fabrics.

Safety Medical Mask should comply with China's compulsory GB 19083-2010 standard, with filtration efficiency ≥95% (using non-oily particulate test). It is required to pass the synthetic blood penetration test (to prevent splashing of body fluids) and to meet the microbiological indicators.

N95 mask is one of 9 kinds of anti-particulate masks certified by NIOSH (National Institute of Occupational Safety and Health). "N" means non-oily particles (oil fumes produced by cooking are oily particles, and the droplets generated by people talking or coughing are not oily), "95" means that the filtration efficiency reaches 95 under the test conditions specified by the NIOSH standard %. Moreover, this kind of mask has a good fit with the wearer's face, can filter particles in the air, block pollutants such as droplets, blood, body fluids, secretions, etc., and is a commonly used personal protective equipment for airborne diseases.

N95 is not a specific product name. As long as it conforms to the N95 standard, and products that pass the NIOSH review can be called "N95 masks."

Microbes are non-oily particulate matter. In the classification of anti-particulate masks by the US NIOSH standard, N type is suitable for filtering non-oily particulates. For example, the cooking fumes are oily particulates, and the droplets generated when a person speaks or coughs are not oily.

In China, it is the national standard KN95, which refers to the classification of non-oily particulate masks by the Chinese national standard GB2626-2006. The KN type is suitable for filtering non-oily particulate matter. The digital standards of the two countries are the same. 95 refers to the filtration efficiency ≥95%.

The above three standard filtration efficiency test methods are the same, so the filtration efficiency levels are the same.

In addition, there are European standard FFP2 (oily and non-oily particulate protection, with virus and bacteria protection, filtration rate of about 94%~95%) and European standard FFP3 (oily and non-oily particulate protection, with virus and bacteria protection, filtering The rate is about 99%).

Medical surgical masks are commonly used in operating rooms and other environments where there is a risk of body fluids and blood splashes. They can block blood and body fluids from passing through the mask to contaminate the wearer. At the same time, the filtration efficiency of bacteria is more than 95%, but the filtration efficiency of particles is limited. Most of them are of rectangular design, and the tightness with the face is not as tight as medical protective masks. Common medical surgical masks include strap type, ear hook type, etc.

Viruses are the smallest of the particles that we can touch every day. Our familiar PM2.5 refers to particles with a particle size of 2.5 microns and below, and the virus particle size ranges from 0.02 to 0.3 microns. Isn’t the virus so dangerous?

Safety Medical Mask

This is a common misconception that the mask is a sieve, and particles with a particle size smaller than the sieve can pass through, and particles with a particle size larger than the sieve are blocked out. In fact, the most effective range for N95 masks is the large particles and the smallest particles.

The mask is a multi-layer composite structure. The N95/KN95 mask is composed of the innermost and outermost nonwoven fabric layers, the middle electrostatic layer and the meltblown nonwoven fabric layer, and the medical surgical mask is a nonwoven fabric layer and a meltblown nonwoven fabric. Cloth layer. In addition to supporting the mask, the non-woven fabric layer also functions as a part of the sieve, and particles with a large particle size will be blocked by them. Melt-blown non-woven fabrics have an ultra-fine fiber structure with good filterability and can intercept medium-sized particles. The electrostatic layer plays the role of electrostatic adsorption, especially small particles are very light and will be adsorbed.

The larger the particles, the better the filtering effect, the smaller the particles, the better the adsorption effect, and the medium-sized particles become the most likely to leak through the net. According to a large number of experiments, the particle size range is between 0.2 and 0.8 microns. Therefore, in GB2626-2006 "Respiratory protective equipment-Self-priming filter anti-particulate respirator", the detection of leakage requires that the particle size of the particles is between 0.02 microns and 2 microns, and the median is 0.3 and 0.6 microns.

Some N95 masks have breathing valves. Can we use them?

The breathing valve will open briefly when exhaling, which may cause microorganisms in the mask wearer to enter the environment, or microorganisms in the environment may adhere to the breathing valve and be sucked into the wearer's body. Therefore, although anti-particulate masks and medical anti-particulate masks used to prevent smog and dust follow a unified standard, it is best to choose a style without a breathing valve for antivirus.

From an antimicrobial perspective, the best choice is a compliant, non-respiratory valve medical protective mask (N95/KN95 mask).

Although the protective effect of medical protective masks with high protection level is better, due to the high filter level, good adhesion, and higher respiratory resistance, long-term wearing will increase the respiratory burden and cause discomfort such as difficulty in breathing.

If it is only for daily use and does not go to hospitals and other places where the risk of pathogen infection is high, you can choose a medical surgical mask.

The standards for medical surgical masks also set clear requirements for bacterial filtration efficiency and particle filtration efficiency. Although they cannot effectively block aerosols, they can effectively block the spread of droplets, which is enough for daily protection. Compliant products will clearly print the corresponding standard number on the packaging. The standard adopted by N95 is NIOSH, the standard adopted by KN95 masks is GB2626-2006, the standard adopted by medical surgical masks is YY0469-2011, and the standard adopted by medical protective masks is GB 19083-2010, you can clearly see the standard words on the package when you buy.

The medical face mask supplier reminds you that in addition to choosing the right mask, you also need to use the right one, mainly paying attention to the way of wearing and the time of use. Read the wearing method on the package carefully and confirm the airtightness after wearing it. If you wear glasses and the fog appears on the lens, it must be that the mask is not worn properly.