Protective masks have different designs for different purposes. In terms of materials, most of them are made of cloth, non-woven fabric, paper, plastic and other materials. The fixing method is mostly to tie the head or ears with rubber bands or cloth. All dust masks must cover the mouth and nose to be effective.
1. Gauze mask: can only filter larger particles, and can only be used during normal cleaning work.
2. Surgical mask: It is suitable for use when there are respiratory symptoms such as colds, fevers, coughs, etc., and when going to unventilated places such as hospitals and cinemas.
3. Activated carbon mask: It can absorb organic gas and toxic dust. It has no sterilization effect. It should be replaced immediately when it needs to breathe hard or cannot absorb peculiar smell. It is suitable for painting or spraying pesticide.
4. N95 protective mask: It can block more than 95% of sub-micron particles, and has high respiratory impedance. It is not suitable for ordinary people to wear for a long time, and repeated use should be avoided.
The N95 protective mask is made of thick non-woven fabric, which is mainly used for industrial dust prevention and has no antibacterial effect. There are multiple layers of medical gauze, such a mask has better dust-proof filtering effect, and will play a role in preventing respiratory diseases. However, experts say it should not be worn for a long time, and it may cause dizziness due to lack of oxygen.
In view of the protective effect of N95 protective masks, Feng Yinchang, director of the National Key Laboratory of Urban Environmental Particulate Pollution Prevention and Control, said that it is impossible to imagine or advertise as great. If the particles below PM2.5 are blocked, breathing will be very difficult.
In addition, wearing N95 protective masks should be replaced every 4 hours (some total wearing time can be up to 8 hours), disposable masks cannot be reused. People with weak breathing muscles or poor cardiopulmonary function should wear N95 masks more carefully.
In addition, let’s talk about protective medical masks. Protective medical masks refer to self-priming filter dust-proof medical protective masks that can filter particles in the air and block droplets, blood, body fluids, and secretions. This is a dust mask that can prevent infections caused by airborne infectious agents with a diameter of ≤5μmg or close (≤1m) contact with droplet-transmitted diseases. The use of medical masks includes tightness testing, training, model selection, medical treatment and maintenance.
The N95 mask is one of the nine anti-particulate masks certified by NIOSH (National Institute of Occupational Safety and Health). N95 is not a specific product name. Products that meet the N95 standard and pass the NIOSH review can be called "N95 masks", but patients with cardiovascular diseases should not wear professional black shield masks, especially N95 masks, because this mask is professional antivirus Yes, the texture is very thick. After wearing it, it is easy for the patient to have difficulty breathing and feel dizzy due to lack of oxygen. "Only patients who have been clearly diagnosed need to wear professional masks. If ordinary citizens wear masks, it is best to choose PM2.5 masks with better air permeability.