Disposable mask can be used to prevent dust, the key is to see what you are used to prevent, is to prevent dust or lampblack or harmful gas! If you are in a dust concentration environment for a long time, it is recommended that you use a duplex dust mask. In general, the service life of disposable dust mask is very short. It's very expensive to use. In terms of protection level, Kn90, kn95 and kn100 are generally recommended to use products with high protection level in China. Our factory now uses compound masks, which is quite good. 1) filtration efficiency: under the condition of air flow rate (30 ± 2) l / min, the filtration efficiency of sodium chloride aerosol with aerodynamic median diameter of (0.24 ± 0.06) μ m should not be less than 30%. 2) Bacterial filtration efficiency: under the specified conditions, the filtration efficiency of Staphylococcus aureus aerosol with average particle diameter of (3 ± 0.3) μ m should not be less than 95%; the bacterial filtration rate should be ≥ 95%; the filtration rate of non oily particles should be ≥ 30%. 3) Respiratory resistance: under the condition of filtration efficiency flow, the inspiratory resistance is not more than 49 PA, and the expiratory resistance is not more than 29.4 PA. When the pressure difference △ p between the two sides of the mask for gas exchange is 49pa / cm, the gas flow rate should be ≥ 264mm / s. 4) Nose clip and mask belt: the mask should be equipped with a nose clip. The nose clip should be made of plastic material, and the length of nose clip should be more than 8.0 cm. The respirator Belt should be easy to wear and take, and the breaking strength at the connection point between each mask belt and the mask body should be greater than 10N. 5) Penetration of synthetic blood: after 2ml of synthetic blood is sprayed at the pressure of 16.0kpa (120mmhg) to the outer side of the mask, there should be no penetration on the inner surface of the mask. 6) Flame retardant performance: the mask material should be non flammable material, and the mask should burn for less than 5S after leaving the flame. 7) Ethylene oxide residue: the residual amount of ethylene oxide in the mask sterilized by ethylene oxide should be less than 10 μ g / g. 8) Skin irritation: the primary irritation index of mask material should be ≤ 0.4, and there should be no allergic reaction. 9) Microbiological index: the total number of bacterial colonies is less than or equal to 20 CFU / g, coliform bacteria, Pseudomonas aeruginosa, Staphylococcus aureus, hemolytic streptococcus and fungi shall not be detected. [5] 3. General medical mask the ordinary medical mask is used to block the spatter from the mouth and nasal cavity, and can be used for one-time health care in the general medical environment, with low protection level. It is suitable for general health care activities, such as sanitary cleaning, liquid preparation, cleaning bed unit, etc., or the barrier or protection of particles other than pathogenic microorganisms such as flower powder.

usage method

1. Carefully cover the mouth and nose with a mask and fasten it to reduce the gap between the face and the mask as much as possible;

2. Avoid touching the mask when using it - after touching the used mask, for example, to remove or clean the mask, wash hands with soap and water or alcohol hand sanitizer;

3. Replace the mask with a new clean and dry mask when it is damp or contaminated with moisture;

4. Do not reuse disposable masks. Disposable masks should be discarded after each use.