Masks provide a certain level of filtration for the air entering the lungs. During outbreaks of respiratory infectious diseases or when working in environments contaminated by dust and other pollutants, wearing a mask is highly effective. So, what types of mask protective products are available? Can disposable masks be reused? Here’s a detailed introduction to the criteria for classifying mask protection levels. A mask is a hygienic product used to filter the air entering the mouth and nose.

　　A mask is a hygiene product typically worn over the mouth and nose to filter the air entering these areas, thereby preventing harmful gases, odors, and droplets from entering or leaving the wearer’s mouth and nose. Masks are usually made from materials such as gauze or paper.

　　Masks can be categorized into air-filtering masks and supplied-air masks.

　　What are the commonly used facial protective items?

　　Eyes, ears—goggles, face shields, earplugs, earmuffs

　　Welding personnel are often seen wearing goggles and face shields, primarily to protect their eyes and faces from external hazards.

　　Ear protection devices for noise reduction are generally earplugs or earmuffs.

　　Respiratory organs—masks, face masks

　　Respiratory protective equipment is primarily designed to prevent the human body from inhaling dust and toxic substances from the external environment. Commonly used types include dust masks and gas masks. There are several important considerations when using protective equipment.

　　When using protective equipment, pay attention to its scope of application, maximum load capacity, and expiration date. Follow the instructions for use strictly to ensure your own safety.

　　What are the classifications of protective masks? Detailed introduction to the criteria for classifying mask protection levels.

　　I. Disposable masks

　　The primary material of disposable masks is non-woven fabric, supplemented by a layer of filter cloth. While these masks offer some protection against dust, certain PM2.5 particles, and avian influenza viruses, their ability to block fine particles such as PM2.5 and pathogens like the avian influenza virus is limited.

　　II. Industrial Protective Mask (N95 Type)

　　The primary materials of N95 masks are cotton-like fabric combined with mask-specific filter cotton. Thanks to the tight seal provided by the mask’s overall design, these masks offer excellent filtration and protection against PM2.5 particles and avian influenza viruses. N95 masks provide good protection in environments containing industrial dust and toxic gases, and they have a relatively long service life.

　　3. Cotton mask + standard filter mask

　　The popular PM2.5 masks on the market mainly consist of a layer of cotton fabric combined with a standard non-woven filter sheet. Such masks are not effective at blocking and filtering PM2.5 fine particles, and their ability to block PM2.5 and avian influenza viruses is also limited.

　　4. Synthetic Fiber Masks

　　The primary component of synthetic fiber masks is chemical fiber material. Since these masks themselves do not incorporate any filter materials designed to provide protective barriers, their ability to block and isolate dust is quite limited—and they are unable to effectively block PM2.5 particles or influenza viruses.

　　5. Nano-antibacterial material + activated carbon + ultra-fine fiber filter (nano anti-virus PM2.5-specific mask)

　　This type of mask uses a relatively well-established nanomaterial—nanosilver—attached to the mask fabric. As we all know, nanosilver is effective in disinfecting and purifying drinking water; similarly, it also exhibits strong decomposition and killing effects on tiny pollutant particles such as PM2.5 and bacterial pathogens that adhere to the mask. If possible, you can use an air purifier—specifically, the Chuangpu Jing USB mini air purifier—and keep windows closed during days with heavy smog or haze.

　　The primary material of disposable masks is non-woven fabric, supplemented by a layer of filter cloth. While these masks offer some protection against dust, certain PM2.5 particles, and avian influenza viruses, their ability to block fine particulate matter such as PM2.5 and pathogens like the avian influenza virus is limited.

　　It is understood that COVID-19 is transmitted through close contact and droplet transmission. If you have N95 masks at home, save them for situations where they’re particularly needed—such as when going to the hospital for medical care. If you’re driving alone, you don’t need to wear a mask. When it comes to wearing a mask for personal prevention, the primary consideration should be your individual risk of exposure to the disease. If you’re heading to public places or taking public transportation, it’s recommended that you wear a mask. However, if you’re by yourself, driving alone, or taking a walk in the park without any close contact with others, you don’t necessarily need to wear a mask—in such circumstances, the risk of infection is very low.

　　Can disposable masks be reused?

　　Some physicians recommend that the general public does not need to replace their masks after each use. The general public can decide whether to replace their masks based on how clean they are. In situations where supplies are relatively tight, it is both safe and reasonable to extend the number of times a mask can be used.

　　Among folk traditions, whether to “steam” or “boil” a medical mask—once water enters, the charges in the filter layer will quickly dissipate, significantly reducing the filtration efficiency. Simply coating or spraying alcohol onto the surface of a mask hardly achieves effective disinfection of the mask’s interior. Under the current epidemic conditions, we should not encourage the disinfection and reuse of disposable antiviral masks.

　　Both medical surgical masks and medical N95 masks are “disposable.” However, from the perspective of the designer, unless one is going to a hospital, a large supermarket, or coming into contact with suspected patients—places that pose high risks—ordinary people don’t need to discard a protective mask after just one use. Instead, they can safely reuse such masks two or three times, thereby reducing the consumption of mask resources. For example, after returning home from a walk, one can remove the mask, place it in a well-ventilated area, let it air-dry naturally or sun-dry to remove any moisture, and prevent the buildup of surface bacteria. Once done, the mask can be used again by the same person.

　　How to extend the lifespan of masks

　　Zhong Nanshan said: "Generally, you should change your mask every four hours. However, you don't need to change it every time you put it on. After eating or doing other activities, there's no need to change it again—just fold the inside of the mask inward, and you can keep using it. For example, if you go out to play sports and there aren't many people on the court, there's no need to wear a mask at all."

　　The general public typically doesn't need to wear N95 masks; even ordinary surgical masks can effectively block particles as small as PM0.4. Viruses generally attach to droplets, and some may also adhere to aerosols—though this isn't yet fully confirmed. However, standard surgical masks can still block most of the viruses that are attached to droplets, making them quite effective.

Source of the article: Zhongyan.com (News)