A few days ago, Hubei Red Cross Society released an announcement, donating 18,000 KN95 masks to Wuhan Tianyou Hospital and Wuhan Renai Hospital respectively. It also stated that the KN95 masks could not be used in the first line of the hospital where the new coronary pneumonia treatment was ordered. Protection for health care workers, but can be used for general protection.

Then, it is hotly debated whether KN95 masks can be used for frontline epidemic prevention for health care workers. The most important thing to remember is that it's not just a matter of time, it's a matter of time.

This is the first time I've ever been to a school, and I'm not sure if I'm going to be able to do it. The reporter from Science and Technology Daily had an interview with the deputy director of the Center for Industrial Textiles Engineering of the Ministry of Education and the deputy director of the Non-Woven Materials and Engineering of Donghua University. Professor Jin Xiangyu, the head of the department, has led a project on the development of textiles for protection against SARS virus in response to the SARS epidemic.

1、Is there a difference between KN95 and N95 masks?

Ken Fabian: N95 is the certification level for respirators in the United States and is certified by the National Institute for Occupational Safety and Health (NIOSH). These masks are capable of filtering out more than 95% of non-oil particles at the specified airflow (85 L/min) ( If it can filter more than 99% of particles (aerosols), it is called an N99 mask. . In addition, corresponding to N95, KN95 is a self-priming, filtered anti-smoking device that has been approved by China's GB2626-2006 Respiratory Protection Products. Particulate matter respirator standard approved masks.

KN95 and N95 masks have comparable levels of protection, but follow different national testing standards.KN95 masks follow the Chinese standards, N95 masks follow US standards, both for protection against non-oily particles (experimental sodium chloride particles). The efficiency is not less than 95%.

2、Can KN95 masks be used for first-line protection?

Both KN95 and N95 masks are available in medical and non-medical versions. Among them, the KN95/N95 mask with the "medical" logo can be used for first-line protection during the fight against the epidemic by health care workers. The mask without "medical" mark is not recommended for medical personnel, ordinary people can use. Class 1 or higher masks conforming to GB19083 can achieve 95% filtration and are impermeable to liquids. Medical institutions of all kinds of operations.

The Hubei Red Club this raises questions about this batch of KN95 masks, if the public announcement is true, indeed to the health department to understand, confirmed that the model of the product can not be used for new coronary pneumonia treatment designated hospital first-line health care workers protection, it can be presumed that KN95 masks non-medical this kind of.

3, KN95 / N95 mask why can antivirus?

The filtering mechanism of KN95 and N95 masks is to block these fine particles and build a protective barrier through the high-performance filter layer in the mask.

Therefore, when wearing KN95/N95 that is, respiratory protection supplies self-absorption filtering anti-particle respirator mask, we should pay attention to the fit, should be close to the face, never give the virus, bacteria to stay a "convenient door", it is recommended that caution with the "exhalation valve"

type of mask.

4, KN95 / N95 mask in the medical and non-medical mask what is the difference?

The main difference is the hydrophobic treatment of the outer surface of medical type masks, GB19083-2010 and GB19083-2010. YY0469-2011 medical surgical masks clearly put forward the requirements of "synthetic blood penetration", "surface resistance to moisture". Parameter indicators that clarify the effectiveness of medical protective masks against liquids such as blood and body fluids. In layman's terms, just like water drops on a lotus leaf will roll off, the liquid cannot soak through the surface of the mask, which will be often touched by medical personnel. Alcohol, blood, etc. block it from rapid penetration; non-medical types of KN95/N95 masks do not undergo this special treatment.

The most protective function of the KN95 and N95 masks is the filter layer, which is made of polypropylene meltblown microfiber electret material. The outer surface of the mask is not hydrophobic, and contact with water, alcohol, etc. during application will destroy the structure of the material, so that the filtering effect is not affected. greatly reduced. What's more, blood often contains bacteria, viruses, etc., and hospital scenarios determine the probability of medical personnel being exposed to the patient's blood. environment. Therefore, hydrophobic treatment of the surface of medical masks is essential. And ordinary people encounter alcohol, blood probability is not large, as long as the regular replacement of the mask, the outside of its without this treatment is also harmless.

5, with breathing valve KN95/N95 mask protection effect?

The KN95/N95 masks are also divided into respiratory valve and non-respiratory valve masks. For the mask, breathability and filtration efficiency are always a contradiction, if the filtration effect is good, you will often feel suffocated. . The breathing valve is designed to relieve breath-holding.

Exhalation valve and inhalation valve is a mechanical switch, inhalation closed, exhalation valve open, the air are filtered through the layer "screen" once, when exhaling The valve opens to alleviate the feeling of resistance. The problem is that it's unclear whether this mechanical switch will suddenly break while wearing it, or get caught by tiny particles that allow the Without a filtered layer of air carriers harmful particles can enter. For this reason, medical type masks do not have a breathing valve. At the same time, we also urge the general public to choose non-valve masks, especially when the surrounding environment is harsh, during the fight against the disease. The KN95/N95 masks or medical surgical masks.

6、What should I pay attention to when donating masks and other supplies?

Jin Xian Yu: should be carefully consulted with the manufacturer, and when donating materials marked with detailed information. Such as the donation of masks should be marked medical or non-medical type, whether it is anti-pollen mask, anti-smog mask or KN95/N95 masks, medical surgical masks, etc. Because of the relatively low filtration standards of pollen and haze masks, they are not recommended for frontline healthcare workers, other workers and field Journalists and other people use it.