Gas masks are mainly composed of filter elements, hoods, eye windows, exhalation and communication devices, and headbands. They each have their own responsibilities and at the same time can cooperate tacitly.
According to the principle of protection, it can be divided into filter type gas mask and isolation type gas mask.
Filtered type:
It consists of a mask and a canister (or filter element). The face shield includes components such as the hood, the eye window, the intercom, the breathing valve and the headband (or helmet). The canister is used to purify poisonous gases, and contains a poisonous layer and adsorbent. These two materials can also be mixed to form a filter plate and assembled into a filter element. The lighter (about 200 grams) canister or filter element can be directly connected to the mask, and the heavier canister is connected to the mask through the air duct.
Isolated type:
The mask itself provides oxygen, which can be divided into three types: gas storage, oxygen storage and chemical oxygen. Insulation masks are mainly used in high-concentration toxic air (when the volume concentration is greater than 1%), or in special occasions such as high altitude, underwater or airtight cabins where oxygen is lacking.
In addition to the above two types of gas masks, many countries are also equipped with various types of gas masks. It is formed by replacing the sorbent in the canister or improving the local structure on the basis of the filtering gas mask. Modern gas masks can effectively defend against poisons, biological warfare agents and radioactive dust that may appear on the battlefield. Some of its weight has been reduced to about 0.6 kg, and it can be worn continuously for more than 8 hours. After wearing a gas mask, it can be more convenient to use optics, communication equipment and weapons.