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N95 masks may not be suitable for the elderly and children

2022-03-21 09:18:56ByZhongMengxia
China Textile 2022年6期

By Zhong Mengxia

According to Baidu's health data, in December, the search volume of scientific COVID prevention-related content has surged 15 times, and the search of prevention-related items has risen sharply.After the price increase of medicine and COVID-19 antigen self-test box was out of stock,many consumers turned their attention to masks.Recently, the search popularity of N95 mask has increased by 715%.With the adjustment of pandemic prevention policy in China, people pay more attention to their own health, and many consumers are enthusiastic about buying N95 masks.The price of a single N95 mask ranges from 2 yuan to tens of yuan, and even the demand exceeds supply in some areas.After nearly three years of COVID, we all know that cotton masks, activated carbon masks and sponge masks have almost no effect on disease prevention.Medical surgical masks and N95 series protective masks are recommended and useful to prevent.

Medical surgical mask

Medical masks, also called surgical masks, are meant to protect the wearer from contact with droplets and sprays that may contain germs.A medical mask also filters out large particles in the air when the wearer breathes in.Generally speaking, medical surgical masks are enough for daily use as long as people are not in direct contact with the diagnosed patients.

The surgical mask consists of three layers.It is the outer waterproof layer, usually made by polyester needled felt.Polyester staple fiber is made into non-woven fabric by needling, therefore,water molecules and droplets are difficult to pass through.The middle layer is a filter layer, usually made by fused non-woven fabric, the main material of which is polypropylene.This nonwoven fabric is made of numerous superfine and electrostatic short fibers, which can adhere most of the droplets and dust to the dense short fibers, thus greatly reducing the infection risk of people.The inner layer is a comfort layer, also known as moisture absorption layer, usually is a kind of hot-rolled non-woven fabric,which can absorb the moisture exhaled by the wearer and improve the wearing comfort.

N95 protective mask

During the coronavirus pandemic, masks,once relegated to specific professions, are quickly becoming commonplace.Not all masks are the same.N95 medical mask is one of nine kinds of anti-particle masks certified by the National Occupational Safety and Health Center of the United States.N means non-oil resistant particles.Under the testing conditions specified by the National Institute of Occupational Safety and Health, the filtration efficiency reaches 95%.As long as the mask meets and passes this examination, it can be called N95 mask.At the same level, there are KN95 masks which meet the standard of GB2626-2019 respiratory protective articles in China.

The biggest feature of N95 mask is that it is designed to fit the face and seal the nose and mouth, thus improving the protective effect.Medical staff exposed to highly infectious bacteria and viruses must wear masks above N95 standard to prevent infection caused by splashes of patients'bodily fluids or blood.The masks filter out contaminants like dusts, mists and fumes.The minimum size of.3 microns of particulates and large droplets won’t pass through the barrier, according to the Centers for Disease Control and Prevention (CDC).

N95 mask has a very good defense effect, and basically can filter all droplets.However, it has not a great air permeability and respiratory resistance, especially for the elderly and children, and it is not suitable for long-term wearing.

At present, N95 masks are out of stock and its price is too over than its real value, please do not worry too much if you didn’t get any these masks.N95 mask must be kept airtight to achieve 95% filtration efficiency.Ordinary people may not wear it correctly, or they can not fit their faces completely, or they often take off their masks for air when they feel uncomfortable, so the efficiency of N95 is also greatly reduced.Therefore, if you can't buy it, medical surgical masks can achieve similar efficacy like N95, and have better comfort for people’s daily uses and activities in general public places.

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