What You Must Know about Masks?

1. Mask grade standard type

Masks are divided into three standard types: N stands for American standard, FFP is a European standard, and KN is Chinese standard. Different standards have the same effect on the same level, such as N95 and KN95. If you donate such products, some hospitals will obtain registration certificates.

Mask level:

The European standard P is divided into three levels of P1 (FFP1), P2 (FFP2), and P3 (FFP3) according to the tested particle transmission rate. The minimum filtering effect of FFP1 is 80%, the minimum filtering effect of FFP2 is 94%, and the minimum filtering effect of FFP3 is ≥97%.

Chinese standard KN: Its detection method is the same as that of the United States. According to China's GB2626-2006 standard, masks are classified into KN and KP types. KN means that the mask is suitable for filtering non-oily particles, and KP means that the mask is suitable for filtering oil and Non-oily particles. The number after the letter represents the protection level of the mask. The larger the number, the higher the protection level.

American Standard N / R / P

1. N95, N99, N100 can filter at least 95%, 99%, 99.97% of suspended particles

N is Not resistant to oil, which can protect non-oily suspended particles. For example, the oil fume produced by cooking is oily particulate matter, and the droplets produced by people speaking or coughing are not oily. Generally, non-oily particles refer to coal dust, cement dust, acid mist, microorganisms, and the like. In the haze pollution currently raging, suspended particles are mostly non-oily. The oily particles refer to oil fume, oil mist, and asphalt fume.

2. R95, R99, R100 can filter at least 95%, 99%, 99.97% of suspended particles

R is Resistant to oil, which can protect non-oily and oily suspended particles, but when used for oily particles, the use time should not exceed 8 hours.

3. P95, P99, P100 can filter at least 95%, 99%, 99.97% of suspended particles

P is the oil proof, which can protect non-oily and oily suspended particles. Compared with the R series, the P series is used for a relatively long time, according to the labels of different manufacturers.

2. Mask process:

Medical-surgical masks are generally made of three layers of non-woven fabric. Material is spunbond non-woven fabric Meltblown non-woven fabric Spunbond non-woven fabric. You can also use short fibers to improve the skin's touch, that is, ES hot-rolled nonwovens, melt-blown nonwovens, and spunbond nonwovens. The outer layer of the mask has anti-fog design, the middle layer is filtered, and the memory absorbs moisture. The melt-blown cloth is generally selected to weigh 20 grams.

The N95 cup mask is made of needle-punched cotton, melt-blown cloth, and non-woven fabric. The melt-blown cloth usually uses 40 grams or more, plus the thickness of needle-punched cotton, so it looks more flat than flat. The mask is thicker and its protective effect can reach at least 95%.

Several layers of masks are not specified in the national standard GB / T32610 for masks. If it is a medical mask, it should be at least 3 layers, which is what we call SMS (2 layers S layer and 1 layer M layer), currently the highest in China. The number of layers is 5 layers, that is, SMMMS (2 layers of Slayer and 3 layers of M layer). It is not difficult to make a mask. The more difficult is to make SMMMS cloth. The price of an imported non-woven fabric is 100 million yuan. The most expensive medical nonwoven equipment I have ever seen is 500 million RMB.

Specific to the mask, all of its raw materials are polypropylene (Polypropylene, referred to as PP), medical masks generally have a multilayer structure, generally referred to as the SMS structure,

3. Questions about the length of wearing the mask:

Medical nursing masks or medical-surgical masks play the main role in the middle filter layer, which will be damaged after long-term wear. It is recommended to replace it every 4 hours.

N95 masks, for long periods of time outdoors or in labor-intensive areas, generally wear this mask for four to six hours. Although it is recommended to use it for 4-6 hours, at present, the actual use time should be 8 -24 hours.

4. How to choose the correct mask

Common masks can be divided into 3 categories: medical-surgical masks, medical protective masks (KN95 Disposable Mask) and ordinary cotton gauze masks, among which medical surgical masks can block 70% of bacteria, N95 masks can block 95% of bacteria, while cotton gauze masks can only block 36% of the bacteria if you go to public places and do not contact the patient, wearing medical surgical masks is enough to avoid excessive protection. No water hand wash gel supplier believes that ordinary cotton protective masks can also achieve dust and foam protection in non-ill areas and non-populated areas.

However, if contacting a patient, wear a bio-resistant N95 mask.

KN95 Disposable Mask

(1) .Medical protective mask (N95)

"Medical protective 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 can filter non-oily particles more than 95% (The meaning of this sentence is to reach N95 level), which is personal protective equipment commonly used to deal with airborne diseases. Common medical protective masks are arched, butterfly-shaped, etc., as shown in Figure 1.

(2) Medical-Surgical Mask

"Medical-surgical masks" are commonly used medical masks in the operating room and other environments where there is a risk of bodily fluids and blood splashes. They can block blood and bodily fluids from passing through the masks and pollute the wearer. At the same time, the filtration efficiency of bacteria is more than 70%, but the filtration efficiency of particles Limited, and mostly rectangular design, the degree of closeness to the face is not as tight as medical protective masks. Common medical surgical masks are strap type, ear hook type, etc.

Mask misunderstanding:

1. Ultraviolet disinfection and dry-dry-wet-steam, which have been circulating in the field, have destroyed the static electricity of the filter layer and the fiber structure, and the filtration performance has dropped to 35%.

2. Even if the sun is used to kill viruses, the mask continuously absorbs the water vapor exhaled by people, which will also cause the charge of the filter layer to be lost, the electrostatic adsorption capacity will be reduced to zero, and the filtering effect will return to about 35%.

3. If the protective effect of the mask made by medical staff is 35%, the effect is the same as that of ordinary cotton cloth. It can be used if it does not enter the crowded area and the hospital area, otherwise it cannot.