Characteristics and device of a gas mask
The filtering gas mask belongs to the means of protection against the destructive effects of various kinds of toxic substances. It is the product of further development of the respirator. This is mainly the isolation of the mucous membranes of the eyes. In addition, the respirator, due to its smaller size, has a shorter service life.
There are many types of gas masks. First of all, they are divided:
- By the type of gas from which it serves as protection.
- By the concentration of harmful impurities in the environment in which the gas mask works.
- Filtration duration.
The ubiquitous distribution of filtering gas masks is due to the high degree of protection on the one hand, and on the other hand, the simplicity of the device. So, its design includes the following elements:
- Face mask. It seals the airway by adhering tightly to the skin. Also, masks act as a kind of frame to which the rest of the gas mask units are attached.
- Glasses. To maintain visual orientation in space, the gas masks are fitted with glasses. They are made of special high-strength glass. The shape of the glasses differs depending on the purpose of the gas masks. Basically it is a teardrop or round shape. But also not uncommon in the military sphere there are face masks with panoramic glasses.
- Inhalation and exhalation valves. Provides air recirculation inside the gas mask. In a sense, they create an air cushion that avoids mixing the incoming and outgoing gases.
- Filter box. Carries out direct cleaning of incoming air from toxic substances. Its main component is a filter made of finely dispersed activated carbon, the frame of which is a fibrous mesh with a fine mesh. This entire system is installed in a special tin box equipped with a thread for attaching to a face mask.
- Transport bag. Required for storing and moving gas masks.
- The above components are integral parts of the gas mask. But, besides this, it can be additionally equipped with:
- A radio communication device to improve communication between the group.
- Connecting hose between mask and filter box. The filter is the most massive part of the gas mask. Moving its center of gravity to another part of the body greatly facilitates the further operation of the gas mask.
- Liquid intake system. Allows you to drink water without removing the protective equipment.
Design features and purpose of use
There are several types of gas masks, but they all have a similar design and work according to the same principle. The most common classification is by way of protection... According to this criterion, gas masks are filtering and insulating.
Regardless of the type, you should put on a gas mask such as GP 7 or PPF-95 so that clean filtered air enters the lungs. The most reliable models are considered to be the GP-7 and GP-7B.
A device of any type consists of a front part and special devices responsible for filtering air or supplying already purified oxygen to the lungs. The face piece is a sealed rubber mask or helmet. In some modern models, rubber has been replaced with plastic. The inhalation and exhalation valves are located on the mask.Sometimes gas masks are equipped with an intercom and an opening for receiving liquids (Figure 2).
Figure 2. Design features of the product are aimed at respiratory protection
Also on the front part there are viewing glasses (spectacle assemblies). Depending on the model, they can be located at eye level, have a frontal or panoramic position. All these structural elements are aimed at ensuring that a person can move freely and inspect the area, while not inhaling smoke or toxic substances. Naturally, for this you should know how to put on a gas mask correctly.
Device and principle of operation
Let us examine in detail what is included in the device of modern filtering gas masks.
Face mask. Thanks to this component, a sufficient sealing of the airways is ensured due to a snug fit. Face masks also act as a kind of frame part, to which all other important parts of the protective device are attached.
The above main parts must necessarily be provided in the device of the device in question. However, this is not all that can be present in gas masks. They are often equipped with additional components.
- Radio communication device. This constituent element is needed to improve communication within the group.
- Connecting hose located between mask and filter box. The filter turns out to be larger and more massive than the gas mask itself. Shifting it away from the center of gravity to another part of the body significantly simplifies the further operation of the protective product.
- Liquid intake system. Due to its action, a person is able to drink water without removing a gas mask for this.
Having figured out what the filtering gas mask consists of, you can proceed to get acquainted with the principle of its operation.
The filtering gas mask itself is based on the action of a chemical adsorption process - this is a special ability of chemical molecules to dissolve in each other. Finely dispersed activated carbon absorbs hazardous and harmful gases into its structure, while allowing oxygen to pass through. This effect explains the high efficiency and relevance of the use of coal.
Components with a low molecular weight and low boiling point may well seep through layers of activated carbon that are as close as possible to each other.
To avoid such consequences, in modern filtering gas masks, additional installations are provided in the form of components that can "weigh down" the incoming gases. This will increase the chance that they can be fully filtered in the device being used. Examples of the materials described are oxides based on copper, chromium and other types of metals.
Rules for the use of gas masks
There are special rules for using gas masks. They greatly facilitate the use of protective equipment.
What you need to know:
- A bag with a complete gas mask is worn over the shoulder. In this case, the belt is on the right shoulder, and the bag is on the left side.
- For convenience and quick response, the height of the bag should be at waist level.
- Before use, an initial inspection is carried out to identify damage and the integrity of all joints and glasses is checked.
- If dirt is found on the surface, it is necessary to clean the filter, mask and all accessories.
How to choose a gas mask?
A person's life depends on the correct choice of a gas mask
It is important to decide not only on the type of gas mask, degree of protection, filter marking, but also to choose the appropriate size. A small one will constrain the movement of the head, crush, and too large will not provide adequate protection.
To select the size, it is necessary to measure the head circumference: in the horizontal and vertical parts.The received data are summed up to obtain one number - in the range from 0 to 4, where:
- 0 - the sum of measurements is less than or equal to 92 cm;
- 1 - total amount from 92 to 95.5 cm;
- 2 - from 95.5 cm to 99 cm;
- 3 - total number from 99 to 102.5 cm;
- 4 - the amount is equal to or greater than 102.5 cm.
For a snug fit, some models are equipped with adjustable straps. As a rule, these are civilian adults and children's gas masks.
How to put on a gas mask correctly
They begin to teach how to put on a gas mask correctly in school educational institutions. In the lessons of Civil Defense (GO), the teacher tells in detail and shows the principle of the competent use of a gas mask. In industrial plants, workers undergo repeated training required for safety.
How to put on a gas mask:
- take the mask with both hands so that the thumbs are on the outside, and the other four are inside;
- hold your breath for a few seconds and close your eyes;
- put on the mask on the face with a quick movement directed from bottom to top;
- straighten the folds;
- exhale the air and open your eyes.
For successful use of a gas mask, it is recommended to pre-train in maintaining an even level of breathing so that the filter works in an even mode. This will significantly extend its service life.