Is the haze very serious in winter in the north? At this time, the anti haze mask will be put into use, so how often does the mask change? The anti haze masks worn by the public are different, including professional anti PM2.5 masks, filter masks, medical masks, pure cotton masks, etc.
"Professional PM2.5 protective masks, such as N95 and n99 masks, shall be replaced after two days of use, otherwise they will not play a good protective role. In addition, this kind of mask is not suitable for wearing for a long time, because of its good airtightness, it is easy for people to have poor breath, lack of oxygen and other conditions. "Li pointed out that the public can choose whether to wear professional PM2.5 respirators according to the daily air quality. If the air quality is good, choose a common mask.
PM2.5 filter mask 8-10 days
During the visit, it was found that many people chose to wear PM2.5 filter masks. This kind of respirator is inserted into the inner side of the ordinary respirator with the functions of PM2.5 prevention, dust prevention and bacteria prevention. The filter is generally disposable, and the wearing time is generally 8 to 10 days (calculated as 8 hours per day). If there is any stain on the filter, it should be replaced immediately.
In addition to the above types of protective masks, disposable masks are also common. Disposable masks can be divided into upper and lower parts. Those with nose clips are the upper part. After wearing the masks, squeeze the nose clips tightly to contact with the skin, so as to prevent the polluted air from entering the mouth and nose. Do not reuse the disposable mask. It should be replaced every 4 hours.
Is haze mask useful
In addition to the above types of protective masks, disposable masks are also common. Disposable masks can be divided into upper and lower parts. Those with nose clips are the upper part. After wearing the masks, squeeze the nose clips tightly and make close contact with the skin to prevent polluted air from entering the mouth and nose. Do not reuse the disposable mask. It should be replaced every 4 hours.
Scientific tests have found that haze masks can block 40-80% of particles. In this test, 80% was blocked; in the sealing test, the effect test was 40-60%. The general impression is that the mask should be changed when it turns black. The filtering efficiency of respirators that meet the national standards will not be reduced after long-term use. The main way to judge whether the masks can continue to be used is to see whether the tightness of the masks is damaged, not only the color change of the masks.
Precautions for replacement of haze mask
Filter effect, not higher better
In the face of a wide variety of anti particle masks on the market, many consumers are dizzy, especially what do the numbers of N, kn, 90, 95 and so on on on the masks mean? The N on the masks represents the American Standard, FFP is the European standard, and kn is the Chinese standard. According to gb2626-2006 standard, masks are divided into kn and KP categories. Kn refers to that masks are suitable for filtering non oil particles, and KP refers to that masks are suitable for filtering oil and non oil particles. The number after the letter represents the protection level of the mask. The larger the number, the higher the protection level. For example, 90 represents more than 90% filtration effect, 95 represents more than 95% filtration effect. How is the protection level converted among three different standard masks? Professionals provide a formula: ffp3 & gt; FFP2 = N95 = kn95 & gt; Kn90.
However, it is not that the higher the filtering effect, the better the mask. Because the higher the filtration effect, the greater the wearer's respiratory resistance. In general, the main pollutants in the atmosphere are non oil particles. Under the condition of the balance of price, protection and comfort, it is enough to choose Kn90 series masks.
If the mask smells, it needs to be replaced
Because the respirator is not cheap, and the manual does not indicate the life of the respirator, many people are reluctant to throw the used respirator. Ms. Liu, a citizen, has two protective masks, one at home and one at work. She can wear them alternately for 20 days, but the masks have already turned black. When she cut open the mask, she found that the innermost layer of the mask did not turn black except for the surface and outer layers. Can such a mask still be used?
To judge whether the mask can continue to be used, we should not only look at the change of surface color. As long as the mask is not damaged or deformed, the hygiene level and respiratory resistance are acceptable, and it can be used continuously. As a daily anti haze use, the service life of the protective mask is mainly affected by hygiene, such as signs of dirt and peculiar smell inside the mask. According to Gu Chaofeng, repeated use of the mask will result in deformation, damage, loose belt or nose clip, which will affect the tightness of the mask. If it is found that the mask is not closed, it should be stopped using and replaced with a new one.
If the respiratory resistance is too high, replace it
Among the numerous particle respirators on the market, there is also a kind of active carbon respirator which is very popular. So, is this kind of mask better in terms of protection?
3M 9042 active carbon mask is also suitable for use in haze days, because it is first of all a particle resistant mask, Kn90 level; the added active carbon layer of the mask has a certain reduction effect on the odor of some organic matters, such as the smell of corruption, and has a certain filtering effect on ozone. In the case of no visible damage or deformation of the active carbon mask on the appearance, it needs to be replaced when the effect of odor reduction is poor or the respiratory resistance is too large.