The first Russian devices, which can be attributed to primitive gas masks, were used when working on the gilding of the domes of St. Isaac's Cathedral in the first half of the 19th century. These were glass caps with hoses through which air was supplied. However, they could not save the craftsmen, who killed 60 people while working with mercury vapor.
A brief history of gas masks
The first gas mask was invented in 1915, during the First World War. Its creator was the Russian scientist N.D. Zelinsky. His invention was adopted by the army at war with Germany in 1916.
The urgent need for gas masks was due to the fact that Kaiser troops first massively used chemical warfare chemical compounds in the war. The first gas attack carried out against the French troops on April 22, 1915, led to the death and disability of thousands of Frenchmen. Germany carried out the second gas attack in the east against the troops of the Russian Empire. And then she became the cause of significant casualties.
Currently, gas masks are used not only in the armed forces, but also in civilian areas. The scope of their application was very wide.
Types of gas masks
By their protective capabilities, gas masks, as a means of protecting the respiratory system, skin of the face, eyes, are divided into three types:
- Filtering gas masks are used to protect against specific types of toxic substances, filtering ambient air; in these devices, as a rule, the filter element is replaced.
- Isolating gas masks are intended for the generation of a respiratory mixture; when used, breathing is carried out through the use of a regenerative cartridge and an oxygen enrichment system.
- Hose gas masks, in which the delivery of the air mixture is carried out at a certain distance, usually 10-40 m.
Advantages and disadvantages of insulating gas masks
Isolating gas masks are universal devices. They have high characteristics for protecting a person from the effects of toxic chemicals. Used with a lack of oxygen. The main feature and main advantage of such gas masks is that the person dressed in them does not breathe in the cleaned air coming from outside, but the clean air mixture from an autonomous source.
The disadvantage of an insulating type gas mask is that it can be used for a limited amount of time. This is due to the fact that the amount of air supplied from an autonomous source is limited. Moreover, they have significant weight, up to 5 kg, which affects freedom of movement.
Varieties of gas masks
By the features of providing oxygen, gas masks of the insulating type are divided into two groups:
- with chemically bound oxygen (pneumotogens);
- with oxygen in compressed form (pneumophores).
The devices of the first type include the widespread IP-4, IP-5 and their modifications (gas mask IP-4M, IP-5M).
The second group of insulating gas masks is a special insulating devices, such as KIP-8, KIP-9. This group also includes insulating gas masks, which use compressed air in their work.
Areas of use for gas masks
Insulating gas masks IP-4 are designed to completely isolate the human respiratory organs from the external environment. When applied, a person breathes due to the work of a regenerative cartridge, which produces clean air.
They are designed to work when a large concentration of toxic substances takes place in the space surrounding a person, if, when using a gas mask of a filter type, a “leakage” of dangerous substances can be expected, which he is unable to prevent. Insulating gas masks IP-4 are used when there is not enough oxygen in the environment, carbon monoxide reaches high concentrations. When it is necessary to carry out a short stay under water, as well as in cases where the types of toxic substances are unknown.
The most common, commonly used insulating type gas masks are IP-4 and MP-5. A type of gas mask IP-4 MK is intended for work in an atmosphere hostile to human breathing, which contains chlorine, ammonia, hydrogen sulfide.
The IP-5 gas mask is also used to perform simple work at a depth, while it can reach seven meters.
A type of gas mask IP-5 (I / 7-5), designed for underwater operations, has an additional device for supplying air.
Components
Isolating gas masks, in which the principle of chemically bound oxygen is applied, consist of the following parts:
- regenerative cartridge and a starting device for it;
- a breathing bag equipped with a valve for relieving excess pressure;
- the front part (mask, helmet) equipped with a connecting tube (it has several sizes, usually three);
- frame;
- satchel with devices.
The regenerative IP cartridge is designed to absorb water vapor and carbon dioxide, which are released by a person upon exhalation, followed by the supply of pure oxygen to the respiratory bag.
It is equipped with a regenerative chemical composition, a starting briquette is mounted in it. When the system starts, sulfuric acid discharged from the briquette (by squeezing the ampoule) heats the regenerative substance. A chemical reaction occurs that ensures the performance of the insulating gas mask. The starting briquette, in addition to starting the cartridge, is designed to release oxygen for several minutes before the time when the main reaction begins.
A breathing bag is an air tank. A valve is built into it to ensure that air pressure is maintained, which should not be higher than 40 mm of water column.
The front part (mask) is intended for isolation from the harmful environment of the facial integuments, respiratory organs, eyes. It provides a supply of clean air from the bag.
The frame protects the breathing bag from external influences, a regenerative cartridge is attached to it.
Features of use
In gas masks IP-4, IP-5, the oxygen supply of one cartridge allows you to work for 45 minutes when performing heavy loads. If the work is carried out at an average pace, then the time spent in it is 70 minutes. At rest, as well as with minor physical stresses, a gas mask can be up to three hours.
The characteristics of the IP-4 gas mask and other similar types allow them to be used continuously, with constant replacement of cartridges, for no more than eight hours. The person is allowed to use the gas mask again, according to the provisions of the current regulatory documents, only after rest for 12 hours.
With constant and periodic use of IP, their use is allowed for 3-4 hours every day for 2 weeks.
It should also be borne in mind that insulating gas masks can ensure reliable operation at temperatures from minus 40 to plus 40 degrees Celsius.
The operational instruction of gas masks IP-4, IP-5, the rules for their use and other regulatory documents established that only those who have passed the special medical commission, course training and practically completed training can work in them.
Contraindications
Contraindications for working in gas masks of an insulating type are all types of tuberculosis, the presence of endocrine problems. It is impossible to work in them for people who have consequences after closed head injuries, neuroinfectious diseases, glaucoma, in the presence of inflammatory diseases of the respiratory organs, as well as for people with diseases of the scalp.
Basic requirements for operation
The main requirements for the operation of the IP, which must be strictly observed, are the following:
- in one room, the number of persons working in insulating gas masks cannot be less than two; continuous communication is required with them;
- the use of non-sealed (not sealed) cartridges is not allowed, as well as the use of a gas mask in case of failure of the starting briquette;
- it is necessary to carefully monitor the state of the regenerative cartridge, if there are signs of emptying (insufficient filling of the bag, difficulty in fully breathing, poor health), immediately stop working in the IP;
- You can not use the PI after removing the mask (front) without installing a new cartridge;
- It is strictly forbidden to lubricate parts and connecting surfaces of the gas mask with grease and oil.
In preparing the gas mask for use, the instruction for its operation requires the presence of an instructor or manager, who are allowed to check the status of the IP.
Preparation for work, storage, disposal
When preparing insulating gas masks IP-4, IP-5 and similar types for use, it is necessary:
- check its staffing;
- conduct an external examination of all gas mask nodes and verify its operability using a pressure gauge;
- pick a helmet in size and make sure it is tight;
- assemble the gas mask, check its condition for leaks.
Insulating gas masks should be stored in a special container, which is sealed and sealed. During storage, it is necessary to subject IP to systematic maintenance.
Spent regenerative cartridges and briquettes must be destroyed. Usually they are burned or dissolved inside the liquid.
When gaining access to the internal contents of regenerative cartridges, as well as when destroying internal substances, spent briquettes, the use of goggles, aprons, and rubber gloves is required.