In terms of protection ability, N99 masks are better than N95 masks. According to the standards promulgated by the National Institute of Occupational Safety and Health, N95 means that the filtering efficiency of the mask for 0.3μm non-oily particles can reach 95%, while the filtering efficiency of N99 can reach 99%. But the price of N99 masks, under normal circumstances, is also 30 yuan 1, now the epidemic environment is only high, the cost of use is much higher than N95 masks. At the same time, because the protection level is higher, the breathing difficulty and discomfort when wearing the N99 mask is greater than that of the N95 mask, and people will feel very uncomfortable after wearing it for a long time, and there is no significant difference in the service life of a single N95 mask and an N99 mask. Therefore, if you are in a high-risk place of epidemic, you can consider buying N99 masks, after all, the protection is stronger, and N95 masks are recommended for general epidemic prevention environment.