N95 respirator is a kind of particle filter mask, conforms to the national institute for occupational safety and health (
N95 filtering air classification, filtering at least 95% of the air particles.
It provides protection for particles, but no protection for gas or steam.
Type N95 respirator masks is considered outside the United States and the regulations of the state, on the function of some breathing respirators are the same.
FFP2 breathing apparatus such as the eu and China KN95 respirator.
N95 respirator requires a fine synthetic polymer fibres, is through a process called melt blown, form the internal filter layer, filter out the harmful particles.
Industrial use N95 respirator was originally for mining, construction and paint industries such as industrial use.
Has been proven to engineering nanoparticles have effective protection.
N series respirators, including N95 masks, only when there is no lubricating oil, cutting fluid, or the oil particles such as glycerol.
For substances harmful to the eyes, it is recommended to use face shield.
In the fire control, lack of oxygen or unknown environment, they have no effect;
In this case, it is recommended to use self-contained breathing apparatus.
Medical use N95 masks had been NIOSH approved respirator, and by the United States food and drug administration (
The Food and Drug Administration, fda)
Approval for the similar surgical masks of medical equipment.
As the family first coronavirus to act, as part of the against covid19 respirator shortages during a pandemic, the responsibility and authentication method modified, allowing the use of N95 mask in the medical environment.
In the United States, the occupational safety and health administration (
Ask hospital staff in patients with suspected or confirmed infection covid19 activities wearing N95 respirator.
Unlike N95 mask, surgical masks designed just for droplets of barrier protection, and there is no air tight seal, so we can not on the same level to protect the wearer from airborne particles (
Such as virus material)
Shortages during the use of N95 mask, not approved as standard care of daily cleaning and reuse.
Their purification and recycle, however, may need to consider as a crisis response strategy, in order to ensure continuous availability.
Duke university researchers published a clean N95 mask method, this method can not damage the respirator, under the condition of using evaporation of hydrogen peroxide for limited number of repeated use.
NIOSH Suggestions, in the case of shortage, type N95 respirator can use up to five times without cleaning, if not for aerosol generation process, respirator has not been the patient's body fluid pollution.
Through on the N95 respirator wear a face mask can be clean, and when used N95 respirator use clean gloves, and immediately after the inspection seal discard gloves, can reduce pollution.
Compared with surgical masks masks is a loose disposable device, it will be on the wearer's forming a physical barrier between the mouth and nose, and pose a potential pollution on the surrounding environment.
Surgical masks, because between the surface and facial mask is very loose, can help stop the larger particles that may contain viruses and bacteria droplets, splash, splash or splash, cannot completely prevent bacteria and other contaminants.
When using NIOSH certification test parameters measurement of different manufacturers face mask, surgical masks filter rate at 10%
Even with a 'good' filter surgical masks, there are 80 -
100% of subjects failed the osha approved qualitative fitting test, and the quantitative test shows that there are 12 -
25% of the leakage, history N95 mask several historical precursor.
One of them is Wu Liande (
Teh Wu, transliteration)
Design of cloth mask.
When the plague broke out in the autumn of 1910, manchuria, Wu Liande court work in China.
Was the first to protect the user from bacterial infections in laboratory tests of the mask, and be used during the 1918 influenza pandemic.
Is another former development during the first world war gas mask, is used by the miners.
They are reusable, but due to its glass fiber filter and heavy rubber structure, bulky and uncomfortable, in the 1970 s, the mining bureau (
And NIOSH made the standard of single use respirator, 3 m company developed the first N95 mask, and was approved in 1972.