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NIOSH N95 Masks and FFP2 with Surgical Mask Protection Efficiency and Wear Time

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Wearing a medical protective mask is one of the most important measures to prevent respiratory infections. The U.S. National Institute of Occupational Safety and Health (NIOSH) and the World Health Organization recommend N95 medical protective masks (“N95 masks”) for the prevention and treatment of respiratory infections, but there are no recommendations on when to wear them. At present, most hospitals, even those with respiratory infections, still mainly wear general medical masks and surgical masks, and a few hospitals that wear N95 masks are more likely to wear them based on their own experience. By comparing the protective efficiency of different masks, and at the same time testing the protection efficiency and breathing resistance of wearing N95 masks at different times, the author evaluates the wear time and protection efficiency of N95 masks, so as to provide reference for personal protection of respiratory infectious diseases.

The filtering effect of different masks compared the filtration efficiency and breathing resistance of several types of masks tested before use, of which the filtration efficiency of N95 masks was the highest, with an average of 97.4%, but its breathing resistance was also the largest, reaching 13. 8mmH2O; surgical masks are the least efficient to filter, at 18. 4%, but its breathing resistance was the lowest, at 1.8mm H2O. The 24-layer gauze mask has a filtration efficiency of 43.9%, slightly higher than the 12th floor, but its breathing resistance almost doubled (6.6:3.9). Shining Star N95 masks brand is doing a good job in this regard.

The filtration efficiency of the N95 mask is gradually reduced with the time of use, and the average filtration efficiency on the third day is 94. 7%, compared with 95% of the standard, the difference is statistically significant (t-6. 26,P=0. 000), but still higher than the European standard EN149:2001 FFP2 and FFP3;

After 5 working days, the filtration efficiency is reduced to 92. 0%;

After 14 working days, the filtration efficiency is still more than 80% (80. 6%).

The breathing resistance of the N95 mask changed little throughout the process, at 11. 4~13. Between 6mmH2O, are well below the national standard of 35mm H2O, the highest resistance value and national standard compared to the difference is statistically significant (t.176.3,P=0.000). BESTG N95 masks is pretty good. RESPOKARE N95 masks brand is doing a good job in this regard.

In fact, surgical masks are not designed to reduce the wearer’s inhalation of pathogens, but to reduce the wearer’s diffission of droplet cores to the outside world.

Therefore, the purpose of the use of various masks should be clear, surgical masks and gauze masks are used to protect others, and medical protective masks are used to protect the wearer himself.