It will be in the fall, and the smoggy weather will gradually increase. At that time, people wearing many kinds of masks will appear in the streets and lanes. However, the mask has a disposable mask, a general mask, a medical mask, an activated carbon mask, and the like. So today, the medical masks and medical masks are all made of high-efficiency electrostatic filter materials, and the appearance of Shanghai is printed with a pattern. So what are the standards when choosing a medical mask? The following small series will introduce you. under.
First, the dust barrier efficiency of the mask. The dust-blocking efficiency of a mask is based on its barrier efficiency against fine dust, especially for respiratory dust below 5 microns. The general gauze mask, the dust-proof principle is mechanical filtration, that is, when the dust collides with the gauze, through the layer of the barrier, some large particles of dust are blocked in the sand cloth. However, for some fine dusts, especially those less than 5 microns, there is no barrier effect. At present, there are some dust masks in foreign countries. The filter material is composed of fibers filled with permanent static electricity. Those less than 5 micrometers of respiratory dust are attracted by static electricity and adsorbed on the filter material during the process of passing through the filter material. It acts as a dust barrier.
Second, the degree of adhesion between the mask and the shape of the face. When the shape of the mask is not close to the face, the dangerous objects in the air will leak from the intimate place and enter the human respiratory tract. Then, even if you choose a good mask for the filter material, you can't guarantee your health. At present, many foreign laws and regulations stipulate that workers should conduct mask adhesion tests on a regular basis. The purpose is to ensure that workers choose the right mask and master the correct wearing method of the anti-fog mask.
Third, the mask is comfortable to wear. The requirements include low respiratory resistance, light weight, hygienic and easy maintenance. This way workers will be willing to wear them in the workplace. There is now a maintenance-free mask that eliminates the need to clean or replace parts. When the dust is saturated or the mask is broken, it can be discarded directly. This ensures the hygiene of the mask and eliminates the time and effort of the worker to maintain the mask. Moreover, many masks are arched to ensure a good fit with the shape of the face and to retain a certain space at the nose and mouth for comfortable wearing.
In addition to high hygiene requirements, medical respirators should also have the function of effectively blocking liquid splashing. The ability of medical mask materials to block pressurized liquids should be relatively high. Only in this way can medical personnel be effectively protected. Therefore, in the standard of medical protective masks, special testing methods are used to test the barrier liquid properties of such products, and the general Black Shield anti-fog masks used in industrial environments do not require such special requirements, and there are naturally no such regulations in the test standards.
In addition, medical respirators are not allowed to have an exhalation valve. This is because when the medical protective mask is used as a surgical mask, if the mask with the exhalation valve is worn, the microorganisms carried in the exhalation will be directly discharged out of the mask, posing a threat to the patient undergoing surgery. Many industrial protective masks have the design of an exhalation valve, but the price of the dust-proof and anti-fog mask with the exhalation valve is much higher than that without the valve.