The mask is used to filter the air in and out of the wearer's mouth and nose, and has achieved the purpose of blocking harmful gases, dust and droplets.
1. Classification of masks
The classification can be made according to the wearing method, materials used, scope of application, protection level and other standards.
1) Classification by shape:
a) Flat plate type is easy to carry, but its sealing is poor;
b) Foldable mask is easy to carry;
c) The cup-shaped breathing space is large, but it is not convenient to carry.
2) According to the way of wearing:
a) Headwear type: it is suitable for workshop workers who wear it for a long time, etc., which is troublesome to wear;
b) Ear wear: easy to wear, suitable for regular wear;
c) Neck wear type: suitable for long-time wear, more convenient to wear helmets or protective clothing and other workshop workers.
3) Classification by materials used:
a) Gauze mask: it can only protect large particles of dust;
b) Non woven mask: mainly in the way of physical filtration and auxiliary electrostatic adsorption;
c) Cloth mask: only warm effect, no filtering fine particle effect;
d) Paper mask: suitable for food and beauty industry, with good air permeability and convenient use;
e) Masks made of other materials: such as new materials for biological protection and filtration.
4) Classification according to applicable scope:
a) Medical masks: they are divided into three categories: medical general masks, medical surgical masks and medical protective masks;
b) Particle respirator: for industrial use, gb2626-2019 standard; for civil use, GB / T 32610-2016 standard;
c) Warm cloth mask: warm cloth mask;
d) Other special industries: chemical industry, etc.
5) According to the protection level:
Different countries and industries have adopted different standards. According to different filtration efficiency of particulate matter, they are divided into different protection grades. In the part of standards, it is introduced in detail.
a) Filter type: it can be divided into air supply filter type and self-priming filter type in detail;
b) Isolation type: it can be divided into air supply type and exhaust type in detail.