The application environments of particulate protective masks are different, and the habits or preferences of the users are also different. In order to meet different needs, these products have their own characteristics in design (see Figure 11). A brief introduction is as follows: Filtration Efficiency level: Table 1, Table 2 and Table 3 respectively introduce the protection levels and classification meanings of particulate protective masks that comply with Chinese standards, American standards and European standards (my country's national standard GB2626-2006, American standard NIOSH42CFR84, European standard EN149-2001 (the most difficult-to-filter particulate matter with an aerodynamic equivalent of about 0.3 microns is used for testing), and the information that should be marked on the mask will be printed on the outer surface of the mask and/or the headband for users to choose: The filtration efficiency ranges from 80 to 90% and can be used for general dust and mist protection (PM2.5 refers to particulate matter with an aerodynamic equivalent of less than or equal to 2.5 microns in ambient air); the range of 94 to 95% can be used for various smoke and fog protection. Protection against pathogenic microorganisms, including dust from highly toxic substances (such as lead dust, asbestos dust, arsenic dust, etc.); ranges from 99 to 99.97% to protect against various types of particles, including radioactive particles (such as radon progeny) or highly toxic particles For particle protection of substances, this filtration efficiency level should be considered as the first choice. Table 1 Classification and grading meaning and labeling method of anti-particulate masks that comply with GB2626-2006 standard Filter material classification Filtration efficiency 90% Filtration efficiency 95% Filtration efficiency 99.97% Mask product surface marking requirements KN category KN90 KN95 KN100 In addition to product model and trademark , marked with the standard number and filtration efficiency level, such as:

GB2626-2006 KN95 KP type KP90 KP95 KP100 KN: suitable for preventing non-oily particles. Non-oily particles such as various dusts, smoke, acid mist, spray paint mist and microorganisms, etc.

KP: Suitable for preventing non-oily and oily particles. Typical oily particles include oil smoke, oil mist, asphalt smoke, particles contained in diesel exhaust and coke oven smoke. Table 2 The meaning and labeling method of the classification and classification of anti-particulate masks in the American standard NIOSH 42CFR84. Filter material classification. Filtration efficiency: 95%. Filtration efficiency: 99%. Filtration efficiency: 99.97%. Mask product surface marking requirements: N category N95 N99 N100 In addition to product model and trademark , also marked with the word "NIOSH", the filtration efficiency level and the NIOSH certification number of this model product. This number can be checked on the NIOSH official website for users to verify the information, such as: NIOSH N95 TC-84A-0007. R category R95 R99 R100 P category P95 P99 P100 N: Suitable for preventing non-oily particles.

R: Suitable for preventing non-oily and oily particles; when used for oily particles, limit use time to 8 hours.

P: Suitable for protection against non-oily and oily particles; when used for oily particles, the use time is limited by the manufacturer. For example, 3M's product regulations are: "If the filter cotton is used to protect oily particles, the use time limit is 40 hours of cumulative use, or 30 days from the beginning of use, whichever comes earlier." Table 3 European standard EN149-2001 classification meaning and labeling method for anti-particulate masks. Filter material classification FFP1* FFP2* FFP3* The surface labeling of mask products requires filtration efficiency of 80% 94% 99%. In addition to the product model and trademark, the European standard number and Filtration efficiency level, and certification body code.

For example: EN149-2001 FFP3 CE0086 *Note: Suitable for preventing both non-oily and oily particles. 2. Whether it is necessary to prevent oily particles: see Table 1, Table 2 and Table 3. For typical examples of oily particles, see the notes on KP below Table 1.

3. For hospital use: The outer surface material of the mask has the ability to block the splash and penetration of pressured body fluids, meets medical requirements, and should comply with GB19083-2010.

4. Cup-type or folding type: Folding-type masks are easy to carry, small in size after folding, and easy to store; cup-type masks may have larger facial space, and the mask is not easy to collapse, which is a traditional design.

5. Whether to have an exhalation valve: The exhalation valve can help reduce the exhalation resistance and facilitate the discharge of hot and humid air in the mask. It is more comfortable and more suitable for high-intensity workers or in hot and stuffy environments. Use below. It is prohibited to use masks with exhalation valves during surgery.

6. How to wear: The mask with two straps on the upper and lower sides is the headband type, and the mask with two straps on the left and right is the ear strap type. The ear loop style is designed to cater to the wearing habits of Asians and has little impact on hairstyle, but it is easy to put pressure on the base of the ears and is not as comfortable as the headband style. There is also a neckband design, which can not only solve the problem of earband compression on the ears, but also solve the inconvenience of headband-type masks that require taking off the hat to remove the mask (see Figure 12).

7. Semicolon type: If protective masks come in different sizes, it may be easier for people with small or large faces to fit the mask tightly.

8. No metal parts are used: The nose clips of most protective masks are made of metal, and many masks use nails to fix the headband. In some special application environments (such as protecting against radioactive aerosols), When disposing of discarded masks, metal parts may make disposal more difficult. Some polymer materials can be used for the nose clip and the headband can be welded to the mask, but this may increase the cost of the mask.

9. Comes with odor reduction: Use a small amount of activated carbon in the filter material to help absorb some unpleasant smelling, low-concentration gaseous substances in the air to achieve the purpose of reducing odor and improving comfort. , but does not increase the protective effect against particulate matter and may increase respiratory resistance.

10. Special for welding: The outer surface of the mask is made of anti-spark material to extend the service life of the mask. It is also equipped with an exhalation valve and/or an activated carbon layer to reduce the feeling of stuffiness and reduce the inhalation generated during welding. Ozone irritates the respiratory tract.

11. Fixing strap material: The fixing straps of the mask are all elastic. In addition to the exposed elastic elastic bands, you can also use elastic bands wrapped with braid on the outside to improve the comfort of the headband on the face. .

12. The length of the fixed strap is adjustable: If the headband can be adjusted in length, it will be more beneficial to users with large faces and reduce the discomfort caused by too tight a headband.

13. Set up a sealing pad on the nose: some can improve the sealing at the bridge of the nose, and some can also help absorb sweat.

14. With facial sealing ring: Adding a sealing ring on the inside of the mask where it is close to the face (see Figure 11) may improve the sealing, or facilitate wiping and cleaning, which will help maintain mask hygiene and extend the use time. .

15. Color: White is the most common, gray is more resistant to stains, and there are other colors to choose from to meet different preferences. Figure 11 Main components of particulate matter protective mask Figure 12 Folding mask using neckband wearing method