Fire safety

Fire - uncontrolled combustion process, accompanied by the destruction of material values and creating danger to life and health of people.

Burning is any reaction of oxidation-reduction, in which heat is released.

In the zone of strong fire there will always be deficit of oxygen, therefore, poisonous carbon monoxide will always be released, therefore, there will always be threat of poisoning. The characteristic of fire is carbon monoxide poisoning.

Carbon monoxide is the strongest known poison. Its action is analogous to the action of cyanides: they form very strong chemical compounds with the atoms of iron, which is part of hemoglobin in blood. Thus, they block hemoglobin and make it unable to carry oxygen to the cells of body.

It is not registered by our senses, since it has no color, no smell, no taste. It does not dissolve in water, therefore, protection of respiratory organs from it with the help of moist tissue is useless and meaningless. Carbon monoxide is not absorbed by a civil gas mask. Exposure to carbon monoxide at concentrations ranging from 1,000 to 10,000 ppm causes headache, dizziness and nausea after exposure for 13 to 15 minutes, loss of consciousness and death if exposure continues for 10 to 45 minutes. With the massive nature of the impact, a person can almost instantly lose consciousness even without any warning symptoms.

Fire components, or necessary and sufficient fire conditions:

FUEL SUBSTANCE + OXIDIZER + IGNITION SOURCE ⇒ FIRE

This approach, on the one hand, highlights the conditions of fire safety (almost always there are combustible substances in the atmosphere of oxygen and the appearance of fire is the result of the emergence of a source of ignition, although other combinations are possible in life), and, on the other hand, it shows the ways of extinguishing fire (removing at least one component from the circuit will lead to cessation of combustion).

Combustible substances - fuel (wood, peat, stone and charcoal, slate, oil and products of its processing), dry plants (hay, straw, etc.), cotton, paper, lubricants, polymeric materials, etc. Oxidizers - oxygen, halogens (Cl2, Br2), nitric acid (HNO3), sulfuric acid (H2SO4), chlorates (KClO3), perchlorates (KClO4), nitrates (NH4NO3), etc.

Ignition sources - flame matches, lighters, candles, etc.; not smashed cigarette butt; molten metal during welding; open fire; static electricity; atmospheric electricity; the sun; electrical equipment; devices; friction.

Combustion products - products of incomplete combustion, poisonous products (carbon monoxide, dioxin - metabolic poison - as a product of burning polyvinylchloride and PVC products - linoleum, pipes, heat and sound insulation blocks, toys, containers, etc., PVC production takes the second place after the production of polyethylene), combustion products of impurities (oxides of sulfur, nitrogen, etc.), solid and liquid particles that form smoke.

Fires can result from:

> careless handling of fire;

> childish prank;

> congestion of the electricity network;

> malfunctioning of electrical equipment;

> household gas leaks;

> accident;

> natural disaster;

> sabotage;

> terrorist act.

The damaging factors of fire and the results of their exposure to humans:

1. Exposure to toxic smoke.

2. Exposure to high temperatures, incl. hot air.

3. Deterioration of visibility.

4. Electric shock.

5. Collapse of structures.

6. Explosion.

7. Panic (especially in venues for entertainment events, hotels, etc.) The consequences of fire for person and his health are as follows:

1. Poisoning.

2. Strangulation (lowering the oxygen content in the air by 3%

significantly impairs motor functions, and by 14% - completely violates

coordination of human movements).

3. Burns of the body and respiratory tracts (inhalation of hot air (temperature above 100°C) leads to necrosis of the respiratory tract, suffocation, loss of consciousness and death in a few minutes).

4.

5. Electric shock.

6. Paralysis of will of an unprepared person.

The main methods of stopping combustion in extinguishing fires:

1. Removal of combustible materials from the combustion zone (this is realized, for example, by rolling with the help of poles the logs of a burning village house or by the organization of an oncoming fallow, or mineralized strips in extinguishing forest fires, etc.).

2. Insulation of the combustion zone from the access of the oxidizer (from the triad of conditions the oxidizer is excluded, and more specifically - air oxygen by means of foam, powder, sand, dense veil, carbon dioxide, etc.).

3. Cooling of the combustion zone with substances that take away part of the heat that goes to the burning continuation (in this method one of the most important sources of ignition is eliminated from three necessary and sufficient conditions for the occurrence and existence of fire, which we have enclosed in the scheme: it is achieved by the use of water, sand, carbon dioxide, etc.).

4. Dilution of gases reacting in the combustion process with gases that do not support combustion (water vapor, carbon dioxide, nitrogen). This method is based on the fact that the rate of the chemical reaction is less, the lower the concentration of the reacting substances

5. Chemical inhibition of the combustion reaction which can be achieved by using inhibitors-negative catalysts that reduce the reaction rate. Ethyl bromide (bromoethyl) is suitable for the purposes of extinguishing fires.

The primary fire extinguishers include fire extinguishers, asbestos cloth, water, sand, various powders, foam generators, special equipment, etc.

Incompatible fire sources and extinguishing means:

1. Wiring - water.

2. Light flammable and flammable liquids - water.

3. Alkali metals (interacting with water with explosion) - water.

Fire prevention rules:

1. Maintain self-control, the ability to quickly assess the situation and make right decisions.

2. It is necessary to leave the building immediately, using the main and emergency exits, external and internal staircases, improvised means (for the lower floors bed sheets, curtains, etc. are suitable). Do not use the lift! (because whoever started to extinguish is obliged to disconnect the power supply of the burning building). Modern lifts are connected with fire alarms. When they receive a signal, they must automatically go down to the first floor and not answer calls.

3. Call firefighters (name the exact address, your surname, arrange a meeting of the arriving units), inform the others.

4. If the fire is small, try extinguishing it with available tools before the fire brigade arrives.

5. Passing through burning rooms, cover the whole body with wet cloth (coverlet, plaid, blanket, etc.), through smoky rooms move crawling or crouching - there is less chance to suffocate in the smoke.

6. If your clothes catch fire, do not try to escape, but try to knock down the flames rolling on the floor; use water, snow, soil to extinguish.

7. For protection against combustion products, use personal protective equipment, including improvised means. (Carbon monoxide is insoluble in water (therefore protection with damp cloth does not help), it is not absorbed by the filter-absorbing box of a civil gas mask.)

8. When you leave the building on a smoky staircase, move along the wall.

9. Before opening the door to a smoky or burning room, stand on the side of it under the protection of the wall or partition and carefully open it.

10. If the electrical wiring is on, disconnect it.

11. Seek out the injured children in secluded places (under the bed, in the closet, etc.), call them.