The most common dangerous situations in the city. The most dangerous situations and how to get out of them. Dangers in the city and in the countryside 5 dangerous situations in the city

More than 140 million people live in Russia, including about 100 million in cities. The number of cities is constantly growing, and their population continues to increase.

In the process of long historical development in urban settlements, humans have formed a special habitat. It includes natural components: non-living - abiotic (relief, climate, water), and living - biota (plant, animal life), as well as an artificially created component of the urban environment - the technosphere (industrial enterprises, transport, residential buildings). An essential part of the urban environment is the population. All these components constantly interact with each other and develop. Sometimes the result of such interaction and development are various kinds of violations and failures, leading to the emergence of numerous and varied problems.

Natural problems are usually associated with the degradation of natural landscapes. In cities, the main components of the habitat change: the geological structure and terrain, the state of surface and groundwater, climate, soil cover, flora and fauna. All living things in the urban environment try to adapt to these changing conditions. It would seem that the urban environment changes only on the surface of the earth, but in the depths, under houses and asphalt, much remains unchanged. However, this is not the case.

In the distant past, man created intricate underground passages, tunnels, manholes, hiding places under palaces and castles, and used natural voids - caves. In modern cities, communications are sometimes located at a depth of several hundred meters. Rivers are hidden in underground tunnels, metro lines, various pipelines, cable networks, etc. are also laid there.

All these structures and communications significantly affect hydrological conditions (the groundwater level decreases), as a result of which the soil-forming process is disrupted.

For the purpose of improvement, the terrain is changed (hills are leveled in some places, while in other areas, on the contrary, they are filled up). For landscaping, ornamental plants that can survive in the city are brought from various regions.

Resource and economic problems are caused by the large scale use of natural resources, their processing and the formation of various, including toxic, waste, which leads to environmental violations and negative impacts on the health of city residents.

Almost all enterprises are sources of industrial pollution, and since most plants and factories are concentrated in cities, the concentration of harmful substances in the air, soil and water poses a great danger to human health and even life.

The city also means increased noise irritation (from cars and other equipment, alarm systems, various industries). It leads to increased fatigue, decreased mental activity, and physical and nervous diseases. The need for long trips in public transport also causes specific fatigue.

In the city, even the houses themselves are potentially dangerous, especially multi-storey ones, from the roofs of which icicles fall off in winter and spring, and various objects can fall out of windows and balconies. Therefore, in urban environments, additions to headgear such as a pith helmet, hard hat or other protective device are quite appropriate. This will at least to some extent ensure the safety of passersby.

In general, you should carefully look not only up, but also at your feet. City roads and sidewalks can become slippery for a number of reasons, resulting in a large number of injured people, especially the elderly.

Infectious diseases spread faster in cities due to high crowding of people and numerous contacts between them, which can lead to epidemics.

And to top all these troubles, the quality of the natural environment as a whole is almost constantly decreasing in cities.

It happens that vegetation also plays a negative role - in the pursuit of fast-growing and beautiful plants that tolerate the conditions of the urban environment, ornamental plants are imported in large quantities, which can cause various allergic reactions in city residents.

And yet, the greatest danger lies in poor-quality drinking water, polluted air, poor-quality food, increased levels of radioactivity, and strong exposure to electromagnetic waves.

Birds, rodents, insects and microorganisms, which are carriers and sources of diseases, also cause a lot of trouble, breeding in large numbers in city landfills and settling basins.

Today, the population of developed countries and almost half of the population of developing countries live in industrial centers. If in 1950 there were only 5 cities in the world with a population of more than 5 million people (with a total population of 47 million people), then in 1980 there were 26 such cities with a total population of 252 million. In 2000, there were already about 60 cities with a population of over 5 million with a total population of 650 million people.

It is also estimated that per day a city with a population of 1 million people. 625 thousand tons of water, 2000 tons of food, 4000 tons of coal, 2800 tons of oil, 2700 tons of gas and 1000 tons of automobile fuel are required. The waste of such a city is also enormous: 500 thousand tons of wastewater, 2000 tons of solid waste, 150 tons of sulfur compounds, 100 tons of nitrogen oxides are released into the atmosphere.

The car has become one of the main culprits of urban pollution. Only up to 10 kg of rubber dust from tire abrasion enters the air per year from each car. And how many toxic substances are emitted from the exhaust pipe, how much oxygen is absorbed by the car engine and carbon dioxide and carbon monoxide are released, and simply the air is heated by the engines (the heat transfer of 100 thousand moving cars is equal to the heat received from several million liters of hot water).

District heating pipelines release up to 1/5 of the heat passing through them to the outside. Heat transfer from factories and factories, furnaces and boiler houses, various mechanisms and devices also contributes to the heating of the air basin of cities; from these industries 2/5 of the energy of all burned fuel comes into the air. It is not surprising that smoke domes with low air humidity and high temperatures form over large cities. Therefore, thunderstorms occur more often in cities, there are more cloudy and rainy days, but less snow falls (in the center of a large city - by about 5%). The onset of the seasons is shifted in large cities - spring begins somewhat earlier, and autumn is delayed. Natural light, especially in the city center, is 5-15% less than in the suburbs, and wind speed is 20% less. The number of condensation centers (10 times) and fogs (2 times) increases. Every fourth disease is associated with urban air pollution, and carbon dioxide is such that inhaling it for several hours can disrupt brain activity. In the atmosphere of cities, carbon dioxide is 20 times more than in rural areas, and 2000 times more than above the sea. Lead in car exhaust emissions can cause brain disorders and mental retardation in children. In addition, mercury, asbestos and other harmful substances are present in the air of cities. Standing at an intersection all day as a policeman, you can get the amount of harmful substances contained in 5 packs of cigarettes.

Cities are increasingly becoming places unsuitable for the healthy life of people, and all living things in general. It has long been known that the life expectancy of a city dweller has decreased by 10%. The adaptation mechanisms of our body are great, but not endless.

In addition to this, the unfavorable crime situation should be taken into account. The growth rate of crime in cities is 4 times faster than the growth rate of their population.

In general terms, the structure of urban crime is as follows.

The first place is occupied by mercenary crimes, among which theft of personal, state and public property predominates, hooliganism is in second place, and violent crimes are in third place: murder, grievous bodily harm and rape. The number of property thefts in cities is almost twice as high as in rural areas. The frequency of thefts from apartments and hostels, holiday homes and sanatoriums, as well as pickpocketing and vehicle thefts is also significantly higher. A new type of crime has appeared in Russian cities - racketeering (extortion).

The intensity of robberies and assaults related to the taking of personal property in cities is high. As a rule, expensive and scarce personal items, imported audio and video equipment, fur items, and jewelry are stolen.

Factors influencing urban crime include:

In urban settings, traditional forms of social control are less effective. The socializing, coercive role of small groups, including families, in the city in some cases is weakening. In a village where everyone knows each other, this circumstance in itself serves as an element of social control and forces one to take into account the general socio-psychological interconnectedness. The conditions of urban life often do not allow the formation of the same connections and communities.

Some factors of urban life directly influence the development of certain forms of criminal activity. Thus, high population density contributes to, for example, theft and pickpocketing, hiding traces of a crime, it allows criminals to “dissolve” in the mass of people and lead an antisocial lifestyle.

The housing problem and the shortage of basic necessities have a direct impact on the level of domestic crime. It has been established that about 70% of so-called residential hooliganism occurs in communal housing and dormitories. The anonymity of the lifestyle gives rise to a psychological attitude in individuals toward impunity and irresponsibility for illegal behavior.

Finally, in the city there is a larger number of people with criminal records than in the village, which affects the rates of recidivism.

Radical and sometimes painful reforms in almost all spheres of life have given rise to a number of phenomena in cities that are becoming serious criminogenic factors. Among them:

• * economic instability;
• * increase in unemployment rate;
• * increasing stratification of the population by income level;
• * changes at the level of state policy in ideological attitudes regarding property, means of production and the psychological unpreparedness of many people to perceive these changes;
• * power deficit;
• * manifestation of bureaucracy and the spread of corruption in the state apparatus.

This obviously explains the high rates of crime growth in recent years and, in particular, the increasing incidence of mass antisocial manifestations, often accompanied by grave consequences (murder, bodily injury, arson, pogroms, destruction of property, disobedience to authorities).

Refugees, who are mainly concentrated in cities, are a serious social irritant and crime factor. Here they encounter great difficulties of a housing and property nature, with problems of finding a job, enrolling children in schools and child care institutions, obtaining a means of subsistence, and establishing normative connections with new people.

Many of them, unable to cope with difficulties, begin to earn a living through illegal means, engaging in theft, robbery, robbery, and often organizing criminal communities (gangs) for these purposes.

It is in large cities that various informal youth associations appear. Informal associations are associations of people of a certain social and age group based on a specific lifestyle, perceived by them as elitist, and group value orientations elevated to the rank of absolute. Some of them benefit people, but not all of them.

In the early 80s. XX century New music burst into the life of the country's discos, denying lyricism, excessively heavy, loud, wildly expressive. The frantic drummers struck deafeningly, the guitars rang loudly, the vocalists screamed in an apocalyptic guise, from time to time turning to a guttural roar. The words “Satan”, “Lucifer” (lord of hell), “death”, “grave” sounded forcefully. Vampires, skeletons, demons, monsters grinned from the records.

During the same period, such informals as metal workers appeared, dressed in leather jackets with numerous metal decorations, heavy chains, and rivets. Their wrists were covered with bracelets studded with thorns. Sometimes these bracelets were strung on the arm up to the elbow. There were spikes on the shoulders and boots. The image of a metalhead was complemented by standing hair and cross-shaped earrings in his ears. The number of stable groups of metalworkers ranged from 8-10 to 30 people. They used certain objects to inflict bodily harm. They consumed alcoholic beverages, toxic and narcotic substances.

Punk rock - the spiritual basis of another type of informality - originated in the USA, then was adopted in Great Britain, and from there it migrated to many developed countries. The word “punk” itself appeared in England in the 16th century. and meant “prostitute.” Now the word has a wide range of meanings: youngster, inexperienced kid, petty thief or hooligan, weakling. The appearance of punk was shaped by the inevitable desire to “slap public taste.” The image of punk was constructed under the slogan: “Ugly is beautiful. Shock is great." The very appearance of punks with war paint, like a savage, is aggressive. Cheeks and earlobes pierced with pins, militantly protruding combs or hair twisted into horns, chains that can be used as weapons on occasion, metal spikes, adherence to the most “aggressive” color of the spectrum - the color of blood, fingerless gloves, as if for demonstration animal claws. This is the classic look of punk. Aggression is also demonstrated in behavior, for example, in the greeting ritual among the punks themselves, “physical” methods of communication are actively used - all kinds of brawls, pushes, blows. Sexual desire is the symbolic character of punk. A kind of cult of perversion occupies a special place here. In the appearance of punks, one can trace some signs characteristic of a homosexual (women's hairstyles, perms, bleaching hair with hydrogen peroxide, fluffed unkempt bangs; the use of decorative cosmetics by men; flirtatious exposure of certain parts of the body; unnatural facial expression - languid, lustful, or defiantly showing spoiled mood). “The Game of Idiocy” is also popular among punks. For example, it is allowed to portray mentally disabled people somewhere on public transport.

Informal rockers are sometimes simply called motorcyclists, since the motorcycle is their main form of transport. But such a name does not fully convey the essence of the phenomenon. Firstly, the rocker violates public safety rules, and in many cases deliberately, counting on a certain reaction from others. Secondly, the rocker creates situations that are dangerous to life and health, and he creates them on purpose. Thirdly, getting into these situations (as well as into related scandals, fights, other incidents and troubles) most often is not choosing a specific act of behavior from several possible options, but following certain learned stereotypes. Fourthly, the core of a rocker’s behavior is constant competition (races) with other rockers, motorists, and the police. The race is an obligatory ritual of his life.

“Fans” or “fans” are young people who get emotional release at football, hockey matches and post-match processions. They are distinguished by shoes, scarves, emblems, signs of the club for which they support. “Fans” use brass knuckles, chains, pipes, sticks, etc. as weapons.

Under certain conditions, the listed groups of young people can pose a real danger to people around them, and this should be taken into account in everyday life.

Transport dangers in the city

In the modern world, transport accidents are perhaps the main threat to any person. But if plane crashes, shipwrecks, and train accidents are relatively rare and can happen almost anywhere, then the threat of road accidents is a daily and very real risk in the city, both for pedestrians and motorists.

The everyday risks of the city are still relevant for its residents, as they were tens and even hundreds of years ago. The only difference is that now the list of threats has grown significantly.

Fires are a traditional danger for city dwellers. the modern format of apartment buildings with gas communications and powerful electrical wiring automatically increases the risk of serious consequences.

The already mentioned gas and electrical communications are in themselves significant danger factors in the city. Experience shows how destructive a domestic gas explosion can be, which can happen to anyone, anywhere. Electric current, in turn, is always a risk of electrical injury and short circuits. Unfortunately, such emergencies claim hundreds of lives every year.

In addition, multi-storey buildings are a risk in the city and without any external influences. Every year, hundreds of people die or suffer disabling injuries from falling out of windows or balconies due to freak accidents.

The city as a source of danger from industry should be taken seriously, if only because it is large settlements that, as a rule, become sites for the location of huge factories, factories, power plants with all the ensuing consequences. At the same time, threats from industry can always be considered from two points of view: as a source of constant pollution and as a constant risk of emergency incidents.

In the first case, the metallurgical, chemical, and mining industries are always a supplier of harmful substances into the atmosphere and water that contribute to the development of cancer and other fatal disorders of the body.

The city as an environment of increased danger of man-made disasters is another threat to its residents. First of all, such emergencies always threaten the life and health of enterprise employees. But, in addition to this, at some enterprises large-scale chemical pollution, powerful explosions of materials, and destruction of dams and dams are also possible.

We should also not forget that residents of many modern cities are always threatened by radiation, both as a natural background and as a danger of accidents at nuclear power plants.

Criminal risks in the city

It is obvious that crime is an inevitable companion of human society in principle, and, as a phenomenon, can manifest itself in almost any conditions.

Criminal dangers in the city that pose a threat to life and health are a large group of different types of crimes. Among them:

· Street robberies;

· Attacks based on national and religious hatred;

· Sexual violence;

· Hooligan attacks, street fights;

· Attempts on life of a custom nature or on the basis of personal hostility;

· Domestic quarrels that escalate into personal aggression.

Natural disasters in one way or another, in different manifestations, threaten every inhabitant of the planet. But in the city they usually have a special destructive power due to the high concentration of the population. In addition, multi-storey buildings, streets and communications congested with traffic greatly enhance the effect of many disasters. For example, even if strong earthquakes in open areas are relatively safe, then even small tremors are sometimes sufficient to cause significant destruction of buildings.

Epidemics in the city

Like many other hazards in the city, respiratory protection, in case of immediate danger, use vaccines as recommended by local health authorities.

War for a city dweller

Fortunately, for most countries, military action was and remains a hypothetical threat. However, if this does happen, it is cities that are high-risk zones for all types of armed confrontations. A large concentration of industrial, military, and government facilities greatly increases the risk of bombings, street fighting, and other forms of open violence, up to extreme forms in the form of the use of nuclear weapons.

In the event that war becomes a real threat, any resident of a large city should be prepared to immediately evacuate to less populated and, as a result, safer areas.

Social and economic risks in the city

Life in cities is more dependent on political influence, economic crises, social movements and trends. As a result, it is here that mass unrest, protests, demonstrations, demonstrations, rallies, even revolutions are most likely. Each of these phenomena, to one degree or another, threatens the life, health and property of citizens.

Like wars, socio-economic risks in the city are often considered hypothetical. But they are the ones that require the constant attention of every resident to social processes and a timely response to them.

Psychological danger of the city

The psychological danger of the city is a controversial and controversial topic. However, it is difficult to argue with the fact that it is in megacities that the percentage of suicides, mental disorders, and antisocial behavior is significantly higher. The high rhythm of life and significant social pressure on the individual are always fraught with the most serious consequences. Everyone struggles with such pressure in their own way, and it is always necessary to be aware of the existence of such a threat.

Question number 16. The concept of harmful substances. Potently toxic substances (SPYAS), their states of aggregation and classification. Routes of entry of SDYAV into the human body and their damaging effects.

1) Harmful substances are substances that, upon contact with the body, can cause occupational injuries, occupational diseases or health problems, both during work and in the long-term life of present and subsequent generations.

2) Potently toxic substances (PTTS) - chemical compounds that are highly toxic and capable, under certain conditions (mainly in accidents at chemically hazardous facilities), of causing mass poisoning of people and animals, as well as contaminating the environment. In case of leakage (emissions) of SDYV, lesions are formed. Moreover, during military operations or natural disasters occurring in the area of ​​production, use or transportation of SDYV, the likelihood of such damage increases significantly. They are, as a rule, divided into zones of direct leakage (discharge) of SDYAS and zones of localization of their vapors.

3) Under normal conditions, SDYAV can be in solid, liquid and gaseous states. However, during the production, use, storage and transportation of these substances, their state of aggregation may differ from that under normal conditions, which can have a significant impact on both the amount of toxic substances released into the atmosphere during an accident and the phase-dispersed composition of the resulting cloud.

(1) gases(Two pairs(3) aerosols(4) liquid(5) hard(6) mixed

4) According to the degree of impact on the human body, all harmful substances are divided into four classes:

Extremely hazardous substances (mercury, lead, ozone, phosgene);

Highly hazardous substances (manganese, copper, hydrogen sulfide, caustic alkalis, chlorine);

Moderately hazardous substances (acetone, methyl alcohol);

Low-hazard substances (ammonia, gasoline, ethyl alcohol).

It should be borne in mind that even low-hazard substances with prolonged exposure can cause severe poisoning at high concentrations.

Ways of influence of SDYAV on the human body:

with food and water (oral); through the skin and mucous membranes (cutaneous-resorptive);

by inhalation (inhalation).

6) According to the clinical picture of the lesion, the following types of SDYAV are distinguished:

Substances with predominantly asphyxiating properties.

With a pronounced cauterizing effect (chlorine, phosphorus trichloride);

With a weak cauterizing effect (phosgene, chloropicrin, sulfur chloride).

Substances with predominantly general toxic effects: carbon monoxide, hydrocyanic acid, -ethylene chloride, etc.

Substances that have a suffocating and generally toxic effect.

With a pronounced cauterizing effect (acrylonitrile);

With a weak cauterizing effect (nitrogen oxides, sulfur dioxide).

Neurotropic poisons (substances that act on the conduction and transmission of nerve impulses, disrupting the actions of the central and peripheral nervous systems): organophosphorus compounds, carbon disulfide.

Substances with asphyxiating and neurotropic effects (ammonia).

Metabolic poisons.

With alkylating activity (methyl bromide, ethylene oxide, methyl chloride, dimethyl sulfate);

Metabolism-altering (dioxin).

Question number 17. Basic physical and technical characteristics of the most common SDYAV. (ammonia, chlorine, hydrocyanic acid, etc.)

The physicochemical properties of SDYV largely determine their ability to pass into the main damaging state and create damaging concentrations. The greatest values ​​are the aggregative state of the substance, its solubility in water and various types of organic solvents, the density of the substance and its gas phase, hydrolysis, volatility, maximum concentration, specific heat of evaporation, specific heat capacity of the liquid, saturated vapor pressure, diffusion coefficient, boiling and freezing points , viscosity, thermal expansion and compressibility, corrosion activity, flash point, etc.

Colorless gas with a pungent odor. Let's dissolve well in water. Transported and stored in a liquefied state. Flammable gas. Burns in the presence of a constant source of fire. Vapors form explosive mixtures with air. Containers may explode when heated. The striking concentration is 0.2 mg/l. The lethal concentration is 7 mg/l.

A greenish-yellow gas with a characteristic pungent suffocating odor. Slightly soluble in water. Soluble in carbon tetrachloride, heptane, titanium tetrachloride and silicon tetrachloride. Strong oxidizing agent. Heavier than air. Accumulates in basements and lowlands. Stored and transported in a liquefied state. Explosive when mixed with hydrogen. Non-flammable, but fire hazard. Containers may explode when heated. Supports combustion of many organic substances. The striking concentration is 0.1 mg/l. The lethal concentration is 0.2 mg/l.

3) Hydrocyanic acid

This is hydrogen cyanide, hydrocyanic acid is a colorless transparent liquid. It has a peculiar intoxicating odor, reminiscent of the smell of bitter almonds. At normal temperatures it is very volatile. Its drops in air quickly evaporate: in summer - within 5 minutes, in winter - about 1 hour. It is miscible with water in all respects, and easily dissolves in alcohols and gasoline. Liquid sulfur dioxide is used as a refrigerant and solvent. Dangerous if inhaled, affects the respiratory system. The striking concentration is 0.2-0.4 mg/l. Lethal concentration is 0.1-0.2 mg/l.

4) Nitric acid

A colorless, heavy liquid that smokes in the air. When exposed to light and when heated, it partially decomposes, releasing brown nitrogen oxides. Strong oxidizing agent, mixes well with water. Non-flammable, but sawdust ignites on contact with it. Highly toxic liquid, irritates the respiratory tract, can cause tooth decay and conjunctivitis. The effects of vapors are greatly enhanced by the presence of motor oils in the air. In case of contact with skin, it causes severe burns and ulcers.

5) Sulfuric acid

Colorless, heavy oily liquid, odorless. In air it evaporates slowly. Corrosive to most metals. Strong oxidizing agent. It dissolves well in water. Reacts actively with water, releasing heat and splashing. Non-flammable. Dehydrates the tree. Increases the sensitivity of wood to combustion. Ignites organic solvents and oils. Highly toxic liquid. Dangerous if vapors are inhaled or swallowed with water or food; it causes severe irritation of the upper respiratory tract; upon contact with skin, it causes severe burns and ulcers.

A shiny, silvery-white, liquid, heavy metal. It evaporates noticeably at room temperature; at elevated temperatures, the evaporation rate increases greatly. Dissolves gold, silver, zinc, etc., forming solid solutions (amalgams). Mercury, especially its vapors and chemical compounds, are toxic, dangerous to inhale, and intensely pollute the environment. Once in the human body, it blocks the biologically active groups of the protein molecule, causing acute and chronic poisoning. Has a damaging effect on the central nervous system, cardiovascular, gastrointestinal tract, respiratory organs, liver, spleen, kidneys. The damaging effect usually appears after a certain period of time (in case of acute poisoning, after 8-24 hours).

Question number 18. Maximum permissible concentrations (MAC) of SDYAS as a hygienic criterion for assessing the sanitary condition of the human environment. Maximum permissible concentrations in various environments of the most commonly used chemical substances in the national economy (ammonia, chlorine).

1) The basis of sanitary and hygienic regulation is the concept of maximum permissible concentration. The content of harmful substances in the air should not exceed maximum permissible concentrations (MPC).

MPC of a harmful substance in the air is a hygienic standard for use in the design of industrial buildings, technological processes, equipment, ventilation, for monitoring the quality of the environment and preventing adverse effects on human health.

MPC - concentrations that should not cause diseases or health conditions detected by modern research methods during work or in the long-term life of the present and subsequent generations. Exposure to a harmful substance at the MPC level does not exclude health problems in persons with hypersensitivity. Maximum permissible concentrations for most substances are single-time maximums. According to sanitary and hygienic requirements, the MPC is, as a rule, significantly higher than the MPC for populated areas, since people spend only part of the day at the enterprise and, in addition, children and elderly people with weakened bodies cannot be there. The criteria for air purity for the work area are less stringent due to different requirements for air quality. For example, in a residential area the perception of foreign odors is not allowed to avoid discomfort, and in a work area it is required not to cause harm to health while workers are at work. The entire sphere of environmental regulation and standardization, especially related to technogenic environmental pollution, is in one way or another based on hygienic standards and uses established maximum permissible concentrations (MPC). Using special programs, the values ​​of maximum permissible emissions are calculated - maximum permissible emissions into the atmosphere (MAE), maximum permissible discharge into water bodies (MPD) of certain substances emitted by specific sources (enterprises) of a given territory.

2) The maximum permissible concentration (MPC) of ammonia is: In the air of populated areas: average daily 0.4 mg/m3, maximum one-time 0.2 mg/m3. The air in the working area of ​​industrial premises is 20 mg/m3. In water of reservoirs 2 mg/m3. Odor threshold 0.5 mg/m3. At concentrations of 40-80 mg/m3, severe irritation of the eyes, upper respiratory tract, headache is observed, at 1200 mg/m3 - cough, pulmonary edema is possible. Concentrations of 1500 - 2700 mg/m3, effective for 0.5-1 hour, are considered lethal. The maximum permissible concentration of ammonia for filtering industrial and civil gas masks is 15,000 mg/m3.

3) Maximum permissible concentration (MPC) of chlorine in the air of populated areas: daily average 0.03 mg/m3, maximum one-time 0.1 mg/m3, in the air of the working area of ​​industrial premises is 1 mg/m3, odor threshold 2 mg/m3 . At a concentration of 3-6 mg/m3, a distinct odor is felt, irritation (redness) of the eyes and nasal mucous membranes occurs, at 15 mg/m3 - irritation of the nasopharynx, at 90 mg/m3 - intense coughing attacks. Exposure to 120 - 180 mg/m3 for 30-60 minutes is life-threatening, at 300 mg/m3 death is possible, a concentration of 2500 mg/m3 leads to death within 5 minutes, at a concentration of 3000 mg/m3 death occurs after several breaths. The maximum permissible concentration of chlorine for filtering industrial and civil gas masks is 2500 mg/m3.

Question number 19. Sources of radiation, the concept of ionizing (penetrating) radiation. Types, main characteristics and units of measurement of ionizing radiation.

1) Radiation source - a substance or device that emits or is capable of emitting radiation and constitutes background radiation. There are natural and artificial sources of radiation.

The majority of the world's population receives radiation from natural sources of radiation. Most of them are such that it is absolutely impossible to avoid exposure to radiation from them. Throughout the history of the Earth's existence, different types of radiation fall onto the Earth's surface from space and come from radioactive substances located in the earth's crust. A person is exposed to radiation in two ways. Radioactive substances can be outside the body and irradiate it from the outside; in this case we talk about external irradiation. Or they may end up in the air a person breathes, in food or water and get inside the body. This method of irradiation is called internal.

Radionuclide- atoms of a radioactive substance with a given atomic number and atomic number, and for isomeric isotopes - and with a given energy state of the atomic nucleus.

Artificial.

isotope sources

non-isotopic sources

X-ray tubes, accelerators, synchrotrons, magnetrons

nuclear reactors

2) Ionizing radiation – radiation, the interaction of which with the medium leads to the formation of ions of different signs. This is a stream of particles or quanta that can directly or indirectly cause ionization of the environment. Ionizing radiation combines types of radiation that are different in their physical nature. Among them are elementary particles (electrons, positrons, protons, neutrons, mesons, etc.), heavier multiply charged ions (a-particles, nuclei of beryllium, lithium and other heavier elements); radiation of an electromagnetic nature (g-rays, x-rays).

3) There are two types of ionizing radiation: corpuscular and electromagnetic.

Corpuscular radiation is a stream of particles (corpuscles), which are characterized by a certain mass, charge and speed. These are electrons, positrons, protons, neutrons, nuclei of helium atoms, deuterium, etc.

Electromagnetic radiation is a stream of quanta or photons (g-rays, x-rays). It has neither mass nor charge.

There are also direct and indirect ionizing radiation.

Directly ionizing radiation is ionizing radiation consisting of charged particles having kinetic energy sufficient for ionization upon collision (electron, proton, particle, etc.).

Indirectly ionizing radiation is ionizing radiation consisting of uncharged particles and photons that can directly create ionizing radiation and (or) cause nuclear transformations (neutrons, X-rays and g-radiation).

Ionizing radiation is characterized by a certain radiation energy, measured in eV. An electron volt (eV) is an extra-system unit of energy that a particle with an elementary electric charge acquires when moving in an electric field between two points with a potential difference of 1 volt.

X-ray (R) is a non-systemic unit of exposure dose. This is the amount of gamma or x-ray radiation that in 1 cm^3 of dry air (having a weight of 0.001293 g under normal conditions) forms 2.082 x 10^9 pairs of ions.

1 C/kg is a unit of exposure dose in the SI system. This is the amount of gamma or x-ray radiation that in 1 kg of dry air forms 6.24 x 10^18 pairs of ions that carry a charge of 1 coulomb of each sign.

Absorbed dose (two units)

Rad is a non-systemic unit of absorbed dose. Corresponds to a radiation energy of 100 erg absorbed by a substance weighing 1 gram (one hundredth of a Gray - see).

Gray (Gr.) is a unit of absorbed dose in the SI system of units. Corresponds to 1 J of radiation energy absorbed by 1 kg of substance.

Equivalent dose (two units)

Rem is the biological equivalent of an x-ray (in some books - rad). Non-systemic unit of measurement of equivalent dose.

Sievert (Sv) is the SI unit of equivalent and effective dose equivalent. 1 Sv is equal to the equivalent dose at which the product of the absorbed dose in Grays (in biological tissue) by the coefficient K will be equal to 1 J/kg.

Question number 20. The most dangerous radionuclides, the concept of biological chains of their entry into the human body. The concept of the biological half-life of radionuclides from the human body. Classification of radionuclides according to the possibility of removing them from the body.

1) The most dangerous from the point of view of internal radiation are a-emitting nuclides, since the range of a-particles in a substance is small and their energy is completely absorbed near the location of the radioactive nuclide. The most dangerous radionuclides for humans are those of heavy elements whose nuclei undergo spontaneous fission or α-decay;

2) The migration routes of radionuclides into the human body are different and occur mainly through the following food chains.

Atmosphere – soil (earth, water) – plants (vegetables, fruits) – herbivores (meat, milk) – (transition to humans is possible at any stage)

3) Half-life is the time during which half of the radionuclides that enter the body are eliminated from the human body.

4) Radioactive substances are quickly removed from the body, concentrated in soft tissues and internal organs (cesium, molybdenum, ruthenium, iodine, tellurium), slowly - firmly fixed in the bones (strontium, plutonium, barium, yttrium, zirconium, niobium, lanthanides). Of the large number of radionuclides, the most important ones as a source of irradiation of the population are strontium-90 and cesium-137. Strontium - 90. The half-life of this radioactive element is 29 years. When strontium is ingested, its concentration in the blood reaches a significant value within 15 minutes, and in general this process is completed after 5 hours. Strontium selectively accumulates mainly in the bones and bone tissue, bone marrow, and hematopoietic system are exposed to irradiation. As a result, anemia develops, popularly called anemia. Research has shown that radioactive strontium can also be found in the bones of newborns. It passes through the placenta throughout the entire period of pregnancy, and in the last month before birth, the same amount of it accumulates in the skeleton as accumulated over the entire previous eight months.

Question number 21. Features of external and internal exposure of people to ionizing radiation.

There are two different ways in which radiation reaches and affects body tissue.

The first way is external irradiation from a source located outside the body. It is caused by gamma rays, x-rays, neutrons that penetrate deep into the body, and high-energy beta rays that can penetrate the superficial layers of the skin. Sources of background external radiation are cosmic radiation, gamma-emitting nuclides contained in rocks, soil, building materials (beta rays in this case can be ignored due to low ionization of air, high absorption of beta-active particles by minerals and building structures) .

The second way is internal exposure from ionizing radiation of radioactive substances located inside the body (by inhalation, intake with water and food, penetration through the skin). Both natural and artificial radioisotopes enter the body. When exposed to radioactive decay in the tissues of the body, these isotopes emit alpha, beta particles, and gamma rays. The dose of external radiation is formed mainly due to exposure to gamma radiation. Alpha and beta radiation do not make a significant contribution to the total external irradiation of living organisms, since they are mainly absorbed by air or the epidermis of the skin. Radiation damage to the skin by beta radiation is possible mainly when being in an open space at the time of fallout of radioactive products of a nuclear explosion or other radioactive fallout.

There are a number of features that make internal exposure many times more dangerous than external exposure (for the same amounts of radionuclides):

1. With internal irradiation, the time of irradiation of body tissues increases, since in this case the irradiation time coincides with the time spent in the body (with external irradiation, the dose is determined by the time spent in the radiation exposure zone).

2. The dose of internal radiation increases sharply due to the almost infinitesimal distance to the tissues that are exposed to ionizing effects (the so-called contact radiation).

3. With internal irradiation, the absorption of alpha particles by the stratum corneum of the skin is excluded (alpha-active substances become the most dangerous).

4. With a few exceptions, radioactive substances are distributed unevenly in the tissues of the body, and are selectively concentrated in individual organs, further increasing their irradiation.

The degree of radiation hazard during internal exposure of a person is determined by a number of parameters:

1. Route of entry of radioactive substances into the body (respiratory organs, gastrointestinal tract, skin).

2. Place of localization (deposition) of radioactive substances in the body.

3. Duration of entry of radioactive substances into the human body.

4. Time spent by the emitter in the body (depending on the half-life and half-life of radionuclides).

5. Energy emitted by radionuclides per unit of time (the number of decays per unit of time is multiplied by the average energy of one decay).

6. Mass of irradiated tissue (depends on the location of radioactive substances in the body).

7. Ratio of the mass of irradiated tissue to the mass of the human body.

8. The amount of radionuclide in the body, that is, the number of decays per unit of time and the type of radiation.

Question number 22. Radioactive contamination of the area as a source of negative factors that have a harmful effect on humans, animals and vegetation.

In areas contaminated with radioactive substances, people and animals may experience radioactive injuries caused by both external irradiation and internal irradiation due to the ingestion of radioactive substances into the body. When radioactive substances fall out, a mixed form of damage may develop, both in humans and animals, due to external irradiation and the presence of radioactive substances in the body.

External gamma radiation, like penetrating radiation, causes the same damage in humans and animals. When exposed to penetrating radiation, the body receives a dose in a very short period of time - from tenths of a second to a second, and with external irradiation, the dose accumulates unevenly during the stay in the contaminated area. Depending on the radiation dose, penetrating radiation causes acute radiation sickness in humans and animals. It can range from mild to extremely severe.

Radiation sickness in humans.

Mild degree of illness. A person experiences malaise, general weakness, headache, and a slight decrease in leukocytes in the blood. At this degree of damage, people recover.

Average degree of development. Signs of the disease are malaise, headache, frequent vomiting, dysfunction of the nervous system, and the number of leukocytes in the blood decreases by almost half. People recover within a few months, but complications from the disease are common.

Severe degree of damage. The patient's health condition is very serious, severe headache, vomiting, diarrhea, loss of consciousness occurs, sudden agitation appears, hemorrhages in the skin and mucous membranes, the number of leukocytes and red blood cells sharply decreases, the body's defenses are weakened and various complications appear. Without treatment, the disease often (up to 50%) leads to death.

Extremely severe illness. Symptoms include severe headache, vomiting, diarrhea, loss of consciousness, sudden agitation, hemorrhages in the skin and mucous membranes, the number of leukocytes and red blood cells sharply decreases, the body's defenses are weakened and various complications appear. The disease is very severe and if treatment is ineffective, such a lesion leads to death in 80 - 100% of cases.

In radiation damage to plants, unlike people and animals, the main role is played by beta rather than gamma radiation. This is explained by the fact that beta particles, having a certain mass and lower speed, are more strongly absorbed by plants. Due to the leaves, they have a very large surface of direct contact with particles, which is almost impossible to prevent.

The contribution of beta radiation to the total radiation dose absorbed by plants in the first hours after fallout can be 10 times or more greater than the contribution of gamma radiation, which means that the radiation dose received by plants is 10 times higher than the exposure dose of gamma radiation measured by dosimetry device.

Radioactive substances falling on plants not only contaminate the surface, but are also absorbed inside through the leaves (iodine, cesium), and once in the soil (they linger especially long in its upper layer (5-7 cm), they begin to enter the plants through the root system. Since this requires some time, during which short-lived isotopes decay, long-lived radionuclides, and primarily strontium-90, come from the soil.

Radiation damage to plants manifests itself in slower growth and development, decreased yield, and reduced seed reproduction. The nutritional quality of the crop is also reduced. Severe damage leads to a complete stop of plant growth and death several days or weeks after irradiation. The degree of radioactive damage depends mainly on the magnitude of the received radiation dose and the radiosensitivity of the plant during irradiation.

Question number 23. The concept of a radiation accident and radiation hazardous objects (RHO). Typical ROO. Classification of ROO.

1) Radiation accident - loss of control of a source of ionizing radiation caused by equipment malfunction, improper actions of workers (personnel), natural disasters or other reasons that could lead or have led to exposure of people above established standards or to radioactive contamination of the environment. In this definition of a radiation accident, sources of ionizing radiation refer to man-made sources of ionizing radiation. A radiation accident can be defined as an unexpected situation at a radiation-hazardous facility, caused by a malfunction of equipment or a disruption of the normal course of the technological process, which may result in an external impact of ionizing radiation on personnel and the population , as well as exposure as a result of the ingestion of radioactive substances into the body in doses exceeding radiation safety standards.

Radiation hazardous facility (RHO) is an object where radioactive substances are stored, processed, used or transported, in the event of an accident or its destruction, exposure to ionizing radiation or radioactive contamination of people, farm animals and plants, economic facilities, as well as the environment may occur. natural environment.

3) Typical radiation-hazardous facilities include: nuclear power plants, enterprises for the production of nuclear fuel, spent fuel reprocessing and radioactive waste disposal, research and design organizations with nuclear reactors, nuclear power plants in transport, military facilities.

In the last lesson, we talked about special services that protect the population and emergency warning signals, as well as how to respond to danger signals. Today we will talk about the dangers that await us close to our homes.

In the twentieth century, cities grew with incredible speed and urban populations increased, it is even sometimes called the century of urbanization (Fig. 1).

Rice. 1. Buenos Aires ()

The city has a lot of entertainment, a lot of interesting things. There is a theater, cinema, zoo, playgrounds and much more. But at the same time, the city is also fraught with many dangers. Let's think about which ones. It may seem that in the city it is much safer than, for example, in the desert, where a person risks dying from thirst, hunger or poisonous snakes.

But the city is fraught with many dangers. Compared to rural areas, it provides certain advantages, but also has disadvantages.

If you compare life in a village and in a city, you can notice many differences. For example, thanks to physical labor, rural residents are stronger; less influence of polluting factors ensures them good health. Typically, rural residents are able to provide themselves with food more easily because they grow their own vegetables; they can warm themselves by collecting brushwood in the nearest forest; if necessary, build a temporary shelter. In the case of deprivation of some of the benefits of civilization, such as gas, electricity, running water, it is easier for rural residents to cope than for people in the city (Fig. 2).

Rice. 2. Village residents are less attached to communications ()

In a healthy body healthy mind

Rural residents are usually in better physical shape than city residents. This can be explained by the fact that in the city most people are engaged in mental work, and schoolchildren do not want to attend physical education classes.

But you must understand that sports are not only good for your health, but can also save your life someday.

For example, Denis from Arkhangelsk never thought that his athletics training would be useful to him in everyday life (Fig. 3).

Rice. 3. Playing sports will never be superfluous ()

Returning home late, the guy passed by a tipsy group. The young people began to behave aggressively towards Denis and already wanted to rob the schoolboy, but thanks to his dexterity, he wriggled out of their hands and was able to escape. His pursuers were less physically prepared, so the guy remained unharmed.

Boys often think that running away is a shame, but don’t forget that the best fight is the one that doesn’t take place. Especially if there are many more attackers.

City dwellers do not possess many useful skills that villagers possess, because they are simply not needed in the city. City residents have everything at their fingertips: gas is supplied directly to the stoves; in order to get water, just open the tap; Any food can be bought at the nearest supermarket.

There are a lot of people in the city, but not many of them know each other; often even neighbors don’t know each other. In the village, everyone knows each other, they know who is the antisocial element. If any danger appears, everyone instantly knows about it, and the same applies to new people.

Life in the city is much more dynamic. Many people have to commute an hour or two to work, which requires using public transport or a personal vehicle. This often causes stress and fatigue in people; they have to return from work in the same way, which only increases stress and negatively affects a person’s behavior (Fig. 4).

Rice. 4. Clashes between drivers lead to stress ()

Road and danger

You all know that the greatest danger on the road is faulty vehicles and careless drivers. You are told from a very early age that it is dangerous to play next to the roadway, that you need to look left and right before crossing the road.

In addition to dangerous cars, there are other dangers on the road. The road is very dangerous in winter: due to snowfalls, visibility may deteriorate. Ice, which is a common occurrence on our roads, is dangerous for injuries (Fig. 5). Therefore, both pedestrians and drivers need to be extremely careful on the roads in winter.

Rice. 5. Ice is dangerous for injuries ()

Open sewer manholes and potholes on the road are also dangerous on the road (you may not notice it due to bad weather and injure your leg, or your parents may drive into a pothole and damage their cars or even get hurt themselves). Tram tracks running along roads are dangerous, as you can trip over them and get hurt.

A rural resident works most of the time near his home, so he does not experience the inconveniences that exist in the city. Also, life in the village is more predictable, and therefore calmer.

The entertainment that abounds in the city takes place in the evening, so people have to return home late, which increases the risk of encountering criminal elements.

The health of citizens is threatened by many plants and factories located in cities. Natural disasters can easily deprive city residents of communications, the absence of which greatly complicates life. And accidents at various utility enterprises threaten the life and health of city residents (Fig. 6). Hail, rain, ice, and blizzards increase the number of road accidents.

Rice. 6. Factory emissions are harmful to health ()

Many of the problems described are less relevant for rural residents, because they are less connected to communications. However, the villages have their own problems. Much more often, villages suffer from natural phenomena. For example, floods, storms, and heavy hail can deprive an entire village of crops (Fig. 7). In emergency situations, it is more difficult for rescuers to provide assistance to victims.

Rice. 7. Consequences of bad weather for cereals ()

Powerful disasters can wipe out an entire settlement from the face of the earth. Although particularly dangerous disasters, such as earthquakes or floods, can cause enormous damage to a city, which is especially vulnerable due to population density and dense buildings.

By comparing the features of life in the city and in the countryside, we can identify the main dangers of the city and their causes:

The presence of many communications and the possibility of accidents on them;

People with evil intentions and antisocial elements;

Abundance of transport and its vulnerability in bad weather;

Pollution from factories, factories and transport;

The need to often be in crowded places.

To sum up the lesson, we can conclude that both city dwellers and villagers are affected by all types of unfavorable factors: man-made, natural and social. But rural residents are less vulnerable to man-made and social hazards.

Learn useful skills

We said that rural residents are more adapted to life in nature and have many useful skills. You can get them too.

You will be taught in the “Young Tourist” club to gain skills in lighting a fire in nature, learning how to set up an overnight stay in the forest, and recognizing edible and inedible mushrooms and plants. In addition, it is very interesting, because even traveling around your native land, you will discover a lot of new and interesting things.

The knowledge gained in life safety, biology, and natural science classes will also be useful.

Rice. 8. Film adaptation of the book “The Mysterious Island” ()

Remember the heroes of Jules Verne's adventure novels (Fig. 8), they survived thanks to knowledge and skills. The heroes of the novel “The Mysterious Island” greatly benefited from the extensive knowledge of one of the heroes in natural history. Thanks to the young naturalist, the heroes knew which plants were useful and which were poisonous, and knew which animals were best to hunt.

As they say, you can’t carry knowledge behind your shoulders, so try to learn as much as possible; knowledge and skills can be useful to you both in everyday life and in extreme situations.

Bibliography

1. Fundamentals of life safety: 5th grade: textbook for educational institutions / M.P. Frolov [et al.], ed. Yu.L. Vorobyova. - Moscow: Astrel, 2013, 174 pp.: ill. Polyakov V.V., Kuznetsov M.I. and others, ed. Latchuka V.N. Fundamentals of life safety. 5th grade. - 2012, 160 p.
2. Smirnov A.T., Khrennikov B.O. Fundamentals of life safety. 5th grade. - 2012, 191 p.

1. vigivanie.com ().
2. Video.yandex.ua ().
3. Vetkaivi.ru ().

Homework

1. Answer the questions on page 25. Fundamentals of life safety: 5th grade: textbook for educational institutions / M.P. Frolov [et al.], ed. Yu.L. Vorobyova. - Moscow: Astrel, 2013, 174 pp.: ill.
2. Make a comparative table of life in a village and a city with all the pros and cons
3. * Describe an ideal city to live in.

Dangerous factors are understood as factors that lead to poor health, various injuries and even disability. This kind of property is possessed by systems that have chemically, biologically and technically active components and conditions that do not correspond to human life.

If we talk about an adult, then dangers can await him at work, during vacation or travel, on the street, in transport, and even at home. For children, dangerous factors can be circumstances that arise on the way to school or during a lesson, while playing at home (especially if the child is alone).

All harmful and dangerous factors create various kinds of situations around a person that can become “catalysts” for accidents.

Interpretation of the concept in question

Dangerous situation- this is such an unfavorable environment, within which dangerous and harmful factors of various origins arise, acting as a threat to human life, health, as well as his habitat and property.

In the course of his life, a representative of the human race may find himself in the epicenter of any harmful situation (get injured, get lost, become a victim of an attack, etc.), when it is necessary to mobilize all available forces, skills and abilities. This kind of situation is called extreme(external assistance is excluded or limited).

According to M.P. Frolov, S.V. Petrov, A.T. Smirnov, E.N. Litvinov, extreme situation- this is a set of circumstances of this kind that require the maximum possible effort of all available spiritual and physical strength to protect a person’s health and life. It appears, for example, when a person finds himself in icy water, or in the epicenter of a snow storm, or during a fire.

Nowadays, extreme sports have become popular, where it is necessary to demonstrate all available skills, abilities, and capabilities in order to survive in autonomous, extremely difficult living conditions.

Also, test pilots, rescuers, astronauts, sailors, etc., whose profession is recognized as dangerous, prepare themselves for possible extremely dangerous situations.

Dangerous and emergency situations: distinctive features

Quite often, in a certain territory, due to natural phenomena, environmental disasters, socially dangerous situations, man-made disasters and accidents, the conditions required for the normal functioning of people are violated, and a real threat to their health, life, and property appears. All this (emergency). They require certain efforts from government agencies and the population to prevent and eliminate their consequences.

An extremely dangerous situation can be of a man-made, biological, natural, social-criminal, military, or environmental nature.

Natural emergency– natural disasters of atmospheric, hydro-, lithospheric origin. Under technogenic their nature refers to catastrophes and accidents that occur within the technosphere and that are associated with everyday, industrial human activities, as well as transport. Extremely dangerous situations of a social nature– circumstances contrary to Russian legislation.

Biological emergencies– diseases of the population, animals of a mass nature of infectious origin (episotia, epiphytosis, epidemic). Military extremely dangerous situation- a situation that leads to the use of weapons of all kinds against another state or population. This also includes the suppression of the popular will of one’s own state.

Natural hazards: sources, causes

An outbreak is a dangerous natural process or phenomenon. Dangerous situations of this kind occur for the following reasons:

• earthquake;
• landslide;
• mudflow;
• erosion;
• avalanche;
• strong wind;
• precipitation;
• frost (frost);
• storm;
• volcanic eruption;
• collapse;
• karst;
• tsunami;
• flood;
• tornado;
• drought;
• natural fire;
• fog.

The damaging factors of the above phenomena are a threat to the health and lives of people, as well as agricultural plants, animals, the natural environment and economically important objects. However, not all hazardous natural situations lead to emergencies (they are not recorded in places where a person is not engaged in any activity and does not live). They are formed exclusively when a threat to life, human health or the environment arises due to the occurrence of the situations in question.

Extremely hazardous natural situations– natural disasters (harmful circumstances of geophysical, hydrological, geological, atmospheric and other origin on a scale leading to a catastrophe, which is characterized by a sudden disruption of the normal functioning of the population, destruction and destruction of material assets, death and injury of people and animals).

Classification of natural disasters based on the conditions of their occurrence

They can be divided into the following groups:

1. Meteorological:

• storms (strong, extended air currents moving at speeds over 20 m/s);
• tornadoes (atmospheric vortices that appear in a thundercloud and spread down, as a rule, to the very earth’s surface; they represent a dark cloud arm or trunk with a diameter equal to tens or hundreds of meters);
• hurricanes (atmospheric vortices of large sizes, moving with wind speeds of up to 120 km/h or up to 200 km/h, if we are talking about the surface layer).

2. Geological:

• earthquakes (underground vibrations, tremors of the earth's surface that appear due to sudden ruptures and displacements in the earth's crust or upper mantle and extend over significant distances as elastic vibrations);
• snow avalanches (snow mass that slides or falls from the slopes of mountains (round) and moves at a speed of approximately 20 - 30 m/s).

3. Hydrological (hydrometeorological):

• flood (flooding of an area with water formed due to prolonged rainfall, snowfall, wind surge on the coast, severe snow melting, which causes material damage and damage to human health or even leads to their death);
• tsunamis (sea waves that arise due to the downward or upward displacement of extended zones of the seabed during coastal and underwater earthquakes).

4. Mass diseases - infections (diseases that arise due to the introduction of a living specific infectious agent into macroorganisms (animals, plants, humans): a virus, bacteria, fungus, etc.).

5. Natural fires (uncontrolled burning of vegetation that spreads through the forest).

Man-made emergencies: definition, criteria for assessing their consequences

Extremely dangerous man-made situations– industrial accidents accompanied by the release of chemical substances; explosions and fires; transport accidents (car, sea, river, railway).

Emergency incidents are divided into the following types of accidents:

• with the destruction of technical systems, vehicles, structures and without human casualties;
• disasters (destruction of all of the above means and systems, as well as loss of life).

Criteria for assessing the consequences of any kind of disaster:

• number of victims;
• number of wounded (invalids, deaths from severe wounds);
• long-term mental and physical consequences;
• material damage;
• social and individual upheaval;
• economic consequences.

What can lead to this type of situation?

The causes of dangerous situations (accidents) are as follows:

• miscalculations in the design of modern buildings, insufficient level of their reliability;
• construction work of inadequate quality or deviation from the design plan;
• lack of a clear plan regarding the location of production;
• serious violation of the technical process due to lack of training or lack of discipline or negligence of personnel.

Individual accidents, disasters in transport and industrial facilities may be accompanied by the release of chemical substances, radioactive substances, explosions, fires, etc.

What dangers await drivers on the roads?

Every time a driver gets behind the wheel of his car, he must remember that any vehicle is a source of increased danger; in his hands is the life of those close to him, those in the car with him, and other participants in this road traffic.

The following dangerous situations on the roads (threats) can be identified:

• Head-on collision. In a situation where an oncoming car is not moving in its lane, first of all, the other driver needs to smoothly reduce speed and signal the offender with headlights or a sound signal. Further, if the dangerous road situation worsens (there is a real danger of a collision), it is recommended to immediately reduce the speed and move the car to the right.

• Side collision. In this situation, you should apply extreme braking and try to avoid an accident (give the “offending vehicle” the opportunity to pass first, despite having the right of way). In the case when extreme braking does not produce results, it is necessary to accelerate sharply, thereby bypassing the place of conflict. When performing this maneuver, you should give a warning signal (audio or headlights). In a situation where it is impossible to avoid a collision, you should try to move it from lateral to tangential (turn the steering wheel in the direction of travel of the attacking car).

• A passing collision. It is most often the result of an incorrectly set distance. You should carefully monitor the movement of the vehicle in front, carry out advanced surveillance (determine in advance changes in the road situation that may force the vehicle ahead to brake sharply). If an increase in speed is observed, it is recommended to increase the distance. Braking should be done smoothly to avoid skidding or hitting the following car, and do not forget about giving a warning signal in a timely manner.

These are just some of the dangerous situations on the roads.

Social emergencies

Processes and phenomena of this direction are filled with acute, insoluble contradictions and cataclysms, which in modern times are acquiring a global character. A socially dangerous situation is a harmful situation in a specific territory that has developed due to a dangerous social process or phenomenon that has resulted in human casualties or damage to their health or the environment, significant material losses, and disruption of the normal living conditions of people.

Protection against them is through professional measures that are aimed at eliminating this type of danger. In addition, appropriate training is necessary to enable a person to respond appropriately in dangerous situations.

The following socially dangerous situations can be distinguished:

• wars and related conflicts;
• accelerated population growth;
• insufficient provision of all people with the required resources that are necessary for normal life (fresh water, energy sources, food, etc.);
• distribution of drugs and dangerous diseases;
• uneven social and economic development of different countries;
• environmental pollution;
• negative consequences of scientific development, as well as technology, informatization;
• increase in crime and extremism.

Type of hazardous situations considered

They are:

• without direct physical influence (blackmail, fraud, etc.);
• with direct physical impact (murder, terror, rape, etc.);
• in the form of public protests (riots, revolutions, demonstrations, etc.).

What to do in case of a life threat?

The rules of conduct in dangerous situations are as follows:

1. Crush. First of all, you need to stay on your feet as much as possible. If it is not possible to stand up, you should take a protective pose (bend your legs, cover your head with your hands, turning it in the direction of the crowd). If there is a fire, you need to stay down and breathe through a dampened cloth.
2. snow avalanche. You need to cover your mouth with your hands, creating an air pocket. You should not scream, as in this situation it is necessary to conserve oxygen. It is recommended to remain in this position until the search party arrives.
3. Tornado. First of all, you need to find shelter. In a situation where this cannot be done, it is necessary to establish, as far as possible, its direction of movement. If there is a vehicle in this kind of dangerous situation, you must immediately leave it and start driving in the opposite direction from the “funnel”. In the worst case scenario, you need to lie on the ground, cover your head and hold on to the support you find as tightly as possible.
4. Falling from a mountainside. Do not try to reach the support to avoid a landslide. You need to press your chin to your chest and try to slow down with your feet.
5. Going under the ice. You should get out in the same direction where you entered. If no one is nearby, you need to try to push yourself out using your forearms (spread your arms as wide as possible and lean on the edge of the ice, gradually try to pull yourself up, pushing out first your torso and then your legs, without standing on them).
6. The car ended up in the river. On average, a person has one and a half minutes until the cabin is completely filled with water. The door cannot be opened, so you should open the window as quickly as possible (kick it out if necessary) and free yourself from the seat belt.
7. Seizure in water. You need to immediately turn over on your back and swim to the shore. Next, you need to stretch the place that has cramped, for example, pull your foot towards you.
8. If a person chokes. In a situation where this happened in a public place, you need to stay there, as the chances of others helping you increase. If no one is nearby, you will have to perform the Heimlich maneuver yourself (carry out a sharp blow to the stomach, somewhere between the navel and ribs, using either your own fist or any solid support, for example, a chair).
9. Nuclear explosion. It is possible to survive if a person is outside the radius of the shock wave. First, you should find shelter, if possible underground. In a situation where a person is in the affected area, it is necessary to lie on the ground and close your head for at least half a minute. It is forbidden to look at the flash, as it will instantly blind you.
10. Hostage taking. You should try to escape in the first minutes. If this is not possible, it is best to follow all the stated rules. It is necessary to constantly monitor what is happening and try to determine the reason for the abduction. Attempts to escape should only be made after carefully weighing the risks and chances.
11. Dog attack. It is always necessary to remain calm (do not shout, do not show fear, do not look into the eyes of the animal). Do not allow the dog to be behind your back (in a situation where the animal begins to move in a circle, you must always be facing it). If you have a third-party object in your hands, place it in front of you. The main thing is to protect your face, throat, and chest. Your fingers must be clenched into a fist.
12. Staying outside during a thunderstorm. You need to find a low-lying place and squat down (you need to position yourself as low as possible, but try not to touch the ground). Be sure to cover your ears.
13. A big wave. First you need to try to swim across it. In cases where this is impossible, you need to stretch your legs and arms (distribute the blow, keep your body from plunging to depth). Next, you should take a deep breath and hold your breath until the excitement subsides. You should surface as quickly as possible and breathe.

Introduction ………………………………………………………………………….3

Chapter 1. High danger zones…………………………………... 4

1.1 Street………………………………………………………………………………….. 4

1.2 Modern housing……………………………………………………... 4

1.3 Places where people gather………………………………………………………………... 5

1.4 Transport…………………………………………………………………….. 6

Chapter 2. Negative impact of the urban environment…………………. 7

2.1 Technogenic hazards……………………………………………...... 7

2.2 Environmental hazards…………………………………………………. 8

2.3 Social dangers………………………………………………………………...... 12

Chapter 3. Security system………………………… 14

Conclusion ………………………………………………………………........16

Bibliography ………………………………………………………...17

Introduction.

At the present stage of development, humanity faces acute problems of large cities.

The city, as an artificial habitat created by man, differs significantly from the natural environment. If in nature a person is faced with the influence of external natural conditions, then in society, the most complex phenomenon of which is the city, external influences come primarily from people or from circumstances caused by them.

The city includes components, which include natural components (terrain, climate, water, flora and fauna), an artificially created component - the technosphere (industrial enterprises, transport, residential buildings) and an essential part of the urban environment - the population.

Over the course of long historical development in cities, humans have developed a special habitat. In the process of life, a person is inextricably linked with the urban environment, forming an interacting system with it. This interaction gives both positive (comfort of life) and negative results. The negative result of human interaction with the city is determined by dangers - negative impacts that suddenly arise, periodically or constantly act in the “human - urban environment” system.

A positive result is determined by the fact that the city, as an artificial habitat created by man, allows people to depend less on extreme natural factors than before. The city provides ample opportunities to improve the comfort of living conditions and to develop the spiritual and creative activity of each person.

In connection with the special role of cities in the development of mankind, the question arises of how to maximize the positive and minimize the negative impacts of the city on people. Resolving this issue will be the goal of this work. To solve this issue, it is necessary to identify high-risk zones in the city, talk about the negative impacts of the urban environment on humans, their consequences and ways to combat them. And also indicate the services included in the city’s security system.

Chapter 1. High danger zones.

Knowing and taking into account high-risk areas allows you to predict the development of a possible extreme situation, provide appropriate rules of behavior and thereby ensure your safety.

1.1. Street

This danger zone includes non-residential buildings, courtyard nooks and crannies, deserted streets, vacant lots, and alleys.

Late at night, it is better to avoid such dangerous places: let the path lengthen, but the degree of danger will decrease. But if you had to walk down an alley, you need to stay close to the edge of the sidewalk and away from dark entrances where a suddenly appearing intruder could drag you. You should walk with confidence, holding an umbrella or lantern in your hands just in case.

When walking along the highway, you need to stay on the side where traffic is moving towards you - this way they won’t be able to drag you into a car that’s approaching from behind.

If possible, you should try to avoid contact with anyone. If there is a threat of attack, it is best to flee. If you are unable to escape, you must fight back using available means of self-defense. Having become a victim of a robber or rapist, you should try to remember his face, clothes and other signs and immediately report to the police.

Also, on the street, you should carefully look not only to the sides, but also to your feet. City roads and sidewalks can become slippery for a number of reasons and, as a result, a large number of injured people appear, especially the elderly.

1.2.Modern housing.

In the city, even the houses themselves are potentially dangerous, especially multi-storey ones, from the roofs of which icicles fall off in winter and spring, and various objects can fall out of windows and balconies.

The entrances and elevators of apartment buildings, where attacks most often occur, are also dangerous. To avoid becoming their victim, certain precautions should be taken:

You should not enter the entrance or elevator with strangers or suspicious people;

If you find yourself alone with a stranger in an elevator, you should immediately get out;

When attacked, you need to call for help, ring someone’s doorbell.

Modern home– the center of various networks of communal and individual household services. A modern, comfortable apartment has enclosed, branched electrical wiring throughout the premises, as well as networks of water supply, heating and sewerage pipes. for the disposal of various household wastes. Many kitchens are equipped with gas stoves, which are supplied with gas through pipelines. Under these conditions, a variety of extreme situations are possible. All pipelines in which, as a result of long-term operation and exposure to the environment, are susceptible to corrosion and wear out. Sometimes it is not at all necessary to be a specialist in order to deal with a particular situation and try to prevent serious consequences.

Flooding.

Each section of the pipeline has a central, intermediate and terminal valves (valves). If there is a water leak from the tap, it is necessary to turn off the intermediate tap, and in the event of a serious accident, close the central valve, which is usually located in the basement of the entrance, and the end and intermediate taps - in the apartment. The same should be done in the event of a heating system failure. All emergencies must be reported to the building management, specialists must be called and an attempt must be made to prevent severe flooding of the apartment, since flooding can lead to a short circuit in the electrical wiring, and this, in turn, can lead to electric shock to people and a fire in the house.

Fire.

It is easier to prevent this situation than to cope with its consequences. If a fire occurs, it is necessary to localize the source of the fire by preventing air from reaching the fire. If a fire occurs due to a short circuit in the electrical wiring, you should turn off the electrical distribution switch located on the landing of each floor, then, if possible, turn off the central switch of the entrance. Next, you need to call the fire brigade and begin to extinguish the fire using available means (water, sand, etc.). The main thing in this situation is to notify neighbors about the fire and save people caught in the fire.

Building destruction.

This extreme situation can occur as a result of an explosion or due to the destruction of building structures. In this situation, it is necessary to show determination, courage, and most importantly endurance, to properly organize the rescue of people, to prevent panic (people in a state of panic often throw themselves from the windows of the upper floors). When buildings are destroyed, flooding, fire, and electrical short circuits can occur. In any case, the most important thing in this situation is to organize the rescue of people, especially from the upper floors.

1.3. Crowded places.

Places where people gather, where it is easy for criminals to commit crimes and escape, are areas of increased danger. It can be train stations, parks, cinemas, places of various celebrations, underground passages, etc. .

At train stations, a criminal can hide, getting lost among people, taking any train. With their large crowds, train stations attract mainly thieves and scammers, “homeless people,” since among a large number of people there will always be simpletons who are easy to deceive. While at the station, you should follow the following rules of safe behavior:

Do not leave things unattended;

Do not trust your belongings and luggage to strangers;

Do not exchange large bills for smaller ones unless absolutely necessary;

To avoid becoming a victim of deception, you should not play various lotteries, “thimbles”, or take part in draws and sweepstakes. After standing for a few minutes and taking a closer look at who is constantly playing and winning, you can personally verify that they are the same people.

Parks- favorite gathering places for young people, teenagers, various companies, places for drinking alcohol, and a person in a state of intoxication loses control over himself, attracts robbers and criminals of all stripes. It is easy for a criminal to hide in the park, so you should not go into secluded, remote places, you should stay close to people.

City markets They are also high-risk areas. These are possible places where thieves, robbers, and scammers gather. Here it is also easy for a criminal to hide, getting lost in the crowd.

At night, it is better to avoid dangerous places: the path will be longer, but the degree of danger will be reduced. If possible, you should try to avoid contact with anyone. If there is a threat of attack, it is best to flee. If this is not possible, then you must use all available means of self-defense. Having become a victim of a robber or rapist, you should try to remember his faces, clothes and other signs and immediately report to the police.

1.4.Transport.

All people, regardless of age and status, use different types of vehicles. But not everyone thinks about the fact that modern transport is a high-risk zone. A feature of modern transport is its high energy saturation. The most energy-intensive types of vehicles are trams, trolleybuses, metro and railway transport.

Automobile transport firmly entered the category of the most dangerous. A car accident (disaster) is one of the main causes of death in a modern city. In most cases, a car accident occurs due to non-compliance with basic safety measures and traffic rules, as well as due to insufficient awareness of the consequences of a particular violation of road safety rules. For example, few people know that colliding with a stationary obstacle at a speed of 50 km/h without a seat belt is equivalent to jumping face down from the 4th floor.

About 75% of all accidents in road transport occur due to drivers violating traffic rules. The most dangerous types of violations continue to be speeding, ignoring road signs, driving into oncoming traffic and driving while intoxicated.

Accidents often result from bad roads (mainly slippery ones) and vehicle malfunction (in the first place are the brakes, in the second place are the steering, in the third place are the wheels and tires). The peculiarity of car accidents is that 80% of the wounded die in the first 3 hours due to excessive blood loss.

Many road accidents occur due to the fault of pedestrians. One of the reasons for the occurrence of accidents involving pedestrians is the incorrect behavior of pedestrians on the roadway and incorrect prediction of the nature of their behavior by the driver. The following main violations of the rules of conduct by pedestrians and driver errors that led to an accident can be identified:

Unexpected exit of a pedestrian onto the roadway;

Crossing the roadway outside a pedestrian crossing;

A collision with a pedestrian “rushing” along the roadway in traffic. This is due to the fact that a pedestrian located between streams of moving cars is very frightened, and his behavior is chaotic and defies reasonable logic;

Distracting the driver's attention when performing a maneuver.

Human. Those traveling in transport should also take certain precautions that can reduce the risk of injury in the event of an accident:

In the event of an accident, safety is guaranteed by a stable, fixed position of the body - sitting in a chair, lean forward and place your crossed arms on the chair in front, press it against your hands, move your legs forward, but do not push it under the chair, as a broken chair can damage your legs;

When falling, group yourself and cover your head with your hands. Do not try to stop your fall by grabbing a handrail or anything else. This leads to dislocations and fractures;

Do not fall asleep while driving - there is a danger of injury during maneuver or sudden braking;

If there is a fire in the cabin, immediately notify the driver;

In case of an accident, open the doors using the emergency door release button. If this fails, break the side windows;

If possible, extinguish the fire yourself using a fire extinguisher located in the cabin;

Once you get out of the burning cabin, immediately start helping others.

Metro– this is a huge artificial system, a harmoniously working mechanism.

extreme situations in the metro can arise:

On the escalator;

On the platform;

In a train carriage.

The most dangerous thing to do is to violate the rules of using the subway on an escalator:

While the escalator is moving, hold on to the handrail;

Do not place luggage on the rail, but hold it in your hands;

Don't run on the escalator;

Do not sit on the steps of the escalator;

Use the emergency brake handle if a passenger spills luggage, hesitates when getting off an escalator, or gets stuck in a gap between steps.

Extreme situations on the platform happen less frequently, but it is still better not to go close to the edge of the platform. Someone may accidentally push you while running, you

You yourself may slip; when boarding, the crowd may push a person into the opening between the cars.

If, due to a breakdown or technical problem on the line, your train is stopped in a tunnel, first of all, remain calm and follow all orders of the metro workers.

Chapter 2. Negative impacts of the urban environment.

A person, solving the problems of achieving comfortable and material security, continuously influences the urban environment with his activities and products of activity, generating man-made, environmental and social hazards in the city.

2.1. Technogenic hazards.

Technogenic hazards are created by elements of the technosphere - machines, structures, substances, etc. as a result of erroneous or unauthorized actions of a person or groups of people.

In large, and especially in the largest cities, the historically formed functional zones of industrial, communal, and residential are still preserved through the floorboards. The number of victims from accidents (disasters) in transport, industrial and other facilities is growing. Transport accidents (disasters) were written in detail in the previous chapter, so below we will consider industrial accidents.

Industrial accidents(disasters) arise as a result of the sudden failure of parts, mechanisms, machines and units or due to human negligence and can be accompanied by serious disruptions in the production process, explosions, catastrophic flooding, the formation of fires, radioactive, chemical contamination of the area, injury and death. Accidents (disasters) at potentially hazardous production facilities are especially dangerous: fire hazardous, explosive, hydrodynamically hazardous, chemically hazardous, radiation hazardous. At industrial facilities, emissions or spills of highly toxic substances are possible. There are no guarantees against radiation damage to people associated with possible accidents at nuclear power plants or military facilities with nuclear weapons. It is at these facilities that accidents (disasters) most often occur, accompanied by significant material losses, disruption of living conditions, injury and death.

A person is exposed to significant man-made hazards when entering the area of ​​operation of technical systems, which include transport highways, radiation zones of radio and television transmission systems, and industrial zones. The levels of hazardous exposure to humans in this case are determined by the characteristics of technical systems and the duration of a person’s stay in the hazardous area.

Technogenic activity of cities and associated modifications of the human environment have entailed the need for a closer study of the environmental problem. As a result of environmental problems in industrial cities, the health of the population is deteriorating, the level of morbidity and mortality is increasing, and life expectancy is decreasing.

There are measures for the rational organization of territories taken in order to improve the environmental situation:

Technological (transition to more advanced, “clean” technologies);

Technical (improving devices for purifying discharges into water bodies and emissions into the atmosphere);

Structural (closing and moving polluting industries out of the city and, conversely, developing industries that are environmentally relevant for it);

Architectural and planning (organization of industrial zones, creation of sanitary and protective gaps).

2.2.Environmental hazards.

Cities are increasingly becoming places unsuitable for the healthy life of people, and all living things in general.

Environmental problems of cities, mainly the largest of them, are associated with excessive concentration of population, transport, and industrial enterprises in relatively small areas, with the formation of anthropogenic landscapes that are very far from a state of ecological balance.

The vegetation cover of cities is usually almost entirely represented by “cultural plantings” - parks, squares, lawns, flower beds, alleys. It happens that vegetation also plays a negative role - in the pursuit of fast-growing and beautiful plants that tolerate the conditions of the urban environment, ornamental plants are imported in large quantities, which can cause various allergic reactions in city residents.

Birds, rodents, insects and microorganisms, which are carriers and sources of diseases, also cause a lot of trouble, breeding in large numbers in city landfills and settling basins.

And yet, the greatest danger lies in poor-quality drinking water, polluted air, poor-quality food, increased levels of radioactivity, and strong exposure to electromagnetic waves.

Today, three-quarters of the population of developed countries and almost half of the population of developing countries live in industrial centers. If in 1950 there were only 5 cities in the world with a population of more than 5 million people (with a total population of 48 million people), then in 1890 there were 36 such cities with a total population of 252 million. In 2000, there were already about 60 cities with a population of over 5 million with a total population of 650 million people. The growth rate of the world's population is 1.5 - 2.0 times lower than the growth of the urban population, which today includes 40% of the world's people.

The millionaire city receives about 29 million a year (excluding water and air) of various substances, which, during transportation and processing, produce a significant amount of waste, some of which enters the atmosphere, the other part, along with wastewater, into reservoirs and underground aquifers horizons, another part in the form of solid waste into the soil.

Atmospheric air.

Scientists believe that every year thousands of deaths in cities around the world are linked to air pollution. Atmospheric pollution is responsible for up to 30% of common diseases in the population of industrial centers. Over large cities, the atmosphere contains 10 times more aerosols and 25 times more gases, among which the most widespread are carbon monoxide, sulfur dioxide and nitrogen oxides. When there is a high content of gases and dust (soot) in the air and air stagnation over industrial areas of cities, smog is formed. Smog is especially dangerous when the air is polluted with sulfur dioxide. It affects the human respiratory system and reduces resistance to other harmful impurities in the air (smoke, soil, asphalt and asbestos dust). At the same time, 60-70% of gas pollution comes from road transport. The car has become one of the main culprits of urban pollution. Every year, each car releases up to 10 kg of rubber muzzle into the air from tire abrasion. And how many toxic substances are emitted from the exhaust pipe, how much oxygen is absorbed by the car engine and carbon dioxide and carbon monoxide are released. Lead in car exhaust emissions can cause brain disorders and mental retardation in children.

District heating pipelines release up to 1/5 of the heat passing through them to the outside. Heat transfer from factories and factories, furnaces and boiler houses, various mechanisms and devices also contributes to heating the air basin of cities; from these industries 2/5 of the energy of all burned fuel comes into the air. With low air mobility, thermal anomalies over the city cover layers of the atmosphere of 250 - 400 m, and temperature contrasts can reach 5 - 6 ° C. It is not surprising that smoke domes with low air humidity and high air humidity and increased temperature are formed over large cities. The number of condensation centers (10 times) and fogs (2 times) increases. Every fourth disease among city residents is associated with urban air pollution, and its saturation with carbon dioxide is such that inhaling it for several hours can disrupt brain activity. Home air poses an equally serious danger to human health. According to scientists who compared the air in apartments with polluted city air, it turned out that the air in rooms is 4-6 times dirtier and 8-10 times more toxic. This is caused by exposure to lead white, linoleum, plastic, synthetic carpets, washing powders, furniture that contains a lot of synthetic adhesive, polymers, paints, varnish, etc.

The main sources of indoor air pollution can be divided into four groups:

1. Substances entering the room with polluted air.

2. Products of destruction of polymeric materials.

3. Anthropotoxins (human waste products).

4. Products of combustion of domestic gas and household activities.

Drinking water. Cities consume 10 or more times more water per person than rural areas, and water pollution reaches catastrophic proportions. Wastewater volumes reach 1 m3 per day per person. Therefore, almost all large cities experience a shortage of water resources and many of them receive water from remote sources.

Despite the fact that a person cannot live more than 9 days without water, water is an important cause of cardiovascular diseases and malignant neoplasms. Or rather, not the water itself, but the toxic substances dissolved in it.

A particular problem is water pollution with detergents - complex chemical compounds that are part of synthetic detergents. Detergents are difficult to clean, and up to 50-60% of their initial amount usually ends up in water bodies.

Among industrial wastes discharged into water, in addition to organic compounds, the most dangerous to the body are salts of many heavy metals (cadmium, lead, aluminum, nickel, manganese, zinc, etc.). Even in low concentrations they cause disruption of various functions of the human body. High concentrations of heavy metal salts cause acute poisoning.

The unsatisfactory sanitary and technical condition of water supply structures and networks in cities is the cause of secondary microbial contamination of drinking water during transportation through the distribution system. The reasons for this are wear and tear of water distribution networks (50 percent or more), untimely elimination of accidents and leaks, and lack of preventive disinfection of water pipelines.

Do not drink chlorinated water;

Use only water that has been purified using highly effective purifiers or freezing;

Drink only boiled water!

Radioactivity. In recent years, the issue of the impact of radiation on humans and the environment has attracted the most attention. Speaking about background radiation stokers in residential premises, it is advisable to dwell in more detail on the significance of such a gas as radon. Radiation hazards are created primarily by inhaling alpha-emitting aerosols from the decay products of radon and sodium. People come into contact with radon and thorium everywhere, but mainly in stone and brick houses, when using gas for cooking and heating, and with water. A great danger is the ingress of water vapor with a high content of radon into the lungs along with inhaled air, which most often occurs in the bathroom, where, as studies have shown, the concentration of radon is 3 times higher than in the kitchen and 40 times higher than in residential areas. rooms. Measures to preserve heat in winter can lead to a significant increase in radon concentrations inside residential premises.

The danger of radon, in addition to the functional disorders it causes (difficulty breathing, migraines, dizziness, nausea, depression, early aging, etc.), also lies in the fact that due to internal irradiation of lung tissue, it can cause lung cancer.

In order to reduce the risk of radon exposure, it is necessary to take protective measures:

Ventilate the premises thoroughly;

Use special coatings for floors;

Replace gas stoves in apartments with electric ones;

Use proven materials for the construction of new houses.

Electromagnetic fields as an unfavorable environmental factor in residential and public premises. As a result of many years of observations, it turned out that electromagnetic fields (EMF) pose a huge danger to health, since with prolonged exposure to humans they can cause cancer, leukemia, brain tumors, multiple sclerosis and other serious diseases. EMFs created by various devices that generate, transmit and use electrical energy are a widespread and constantly increasing negative factor in the urban environment.

Currently, there are a huge number of EMF sources located both outside residential and public buildings (power lines, satellite communication stations, radio relay installations, television transmission centers, open switchgear, electric vehicles, etc.) and indoors (TVs, VCRs , computers, cellular radiotelephones, household microwave ovens, etc.)

In cities, there is a significant change in the level of EMF intensity during the day: during the day, during the operation of industrial and municipal enterprises, it increases, and in the evening it decreases. Daily fluctuations in artificial EMF dramatically change the electromagnetic environment of the city as a whole. Naturally, this does not go unnoticed for city residents, many of whom are exposed to EMFs at their workplaces. The main way to protect the population from the effects of external EMFs in a residential area is protection by distance, that is, there must be an appropriate sanitary protection zone between the EMF source and residential buildings. Another reliable way to protect the body from the harmful effects of EMF, the sources of which are household appliances and personal computers, is time protection. That is, the time spent working near such devices should be limited.

Noise in a residential environment. Austrian experts have found that human life expectancy is reduced by 10-12 years due to the noise of large cities. According to sanitary standards, noise in a residential area should be no more than 60 dB, and at night - no more than 40 dB. The limit value of noise that does not cause harmful consequences is 100 dB. However, on busy streets the noise often reaches 120-125 dB. But over the last decade alone, noise in large Russian cities has increased 10-15 times.

The noise “symphony” of a city is made up of many factors: the rumble of railways and the rumble of airplanes, the roar of construction equipment, etc. The most powerful chords in it are the movement of vehicles, which, against the general background, produces up to 80% of the noise.

Noise seriously affects people's well-being and health. Thus, for many young people who listen to loud rock music, their hearing can be permanently damaged. However, noise harms more than just your hearing. A number of studies show that noise can increase blood pressure and cause damage to the cardiovascular system. Excessive noise makes it difficult for students to learn the material, causing irritability, fatigue, and decreased productivity.

High noise levels from televisions and radios in the home have been shown to impede the development of sensorimotor skills in children during the first two years of life. Constant exposure to loud sounds also impedes speech development and suppresses the exploratory instinct.

Statistics show that workers who are constantly in a noisy atmosphere are more likely to develop cardiac arrhythmia, vestibular disorders and other diseases. They more often complain of fatigue and increased irritability.

Against a background noise of approximately 70 dB, a person performing moderately complex operations makes twice as many errors as in the absence of this background. It has also been established that noticeable noise reduces the performance of people engaged in mental work by more than one and a half times, and in physical work by almost a third.

Of course, much in the fight against noise depends on us. For example, if you work in noisy industries, then it is advisable to wear sound-absorbing headphones. If there is a strong source of noise inside the building, the walls and ceiling can be lined with sound-absorbing material, such as polystyrene foam. If you live in a house located on a street with heavy traffic, then during rush hours you should close the windows facing the street and open the windows facing the courtyard. And, of course, do not turn on television and radio equipment at full power, especially in the evening and at night.

To reduce noise in a residential area, the following principles must be observed:

Place low-rise buildings near noise sources;

Noise protection facilities should be built parallel to the transport highway;

Group residential properties into closed or semi-closed neighborhoods;

Buildings that do not require noise control (warehouses, garages, etc.) should be used as barriers to limit the spread of noise.

Vibration in living conditions.

Vibration as a factor in the human environment, along with noise, is one of the types of physical pollution that contributes to the deterioration of the living conditions of the urban population.

Fluctuations in buildings can be generated by external sources (underground and surface transport, industrial enterprises), in-house equipment of built-in trade and public services enterprises. Vibration in an apartment is often caused by the operation of the elevator. In some cases, noticeable vibration is observed during construction work carried out near residential buildings. Vibrations of the floor, shaking of walls, furniture, etc., regularly repeated after 1.5-2 minutes. disrupt residents’ rest, interfere with household chores, and prevent them from concentrating on mental work. People living in such houses experience increased irritability and sleep disturbances. Those most susceptible to the negative effects of vibration are those aged 31 to 40 years and those with diseases of the cardiovascular and nervous system.

The most important direction in solving the problem of limiting the adverse effects of vibration in residential conditions is the hygienic regulation of its permissible effects.

Currently, we can speak with confidence about the complex impact of a number of unfavorable factors that have led to a decrease in the defenses of the body of a city resident and increased susceptibility to various diseases. There is a connection between the geochemical structure of urban pollution and the state of public health, which can be traced at all stages - from the accumulation of pollutants and the occurrence of immunobiological changes in the body to an increase in morbidity. Being a function of many variables, the health of the urban population is an integral indicator of environmental quality.

2.3. Social dangers.

An unfavorable social situation arises as a result of epidemics, the resolution of social, interethnic and religious conflicts by non-parliamentary methods, the actions of gangs and groups, which leads to disruption of the normal functioning of the population, loss of life, destruction and destruction of material and cultural values.

The consequences of an unfavorable social situation in cities can be very different: from the emergence of hazardous living conditions during an epidemic to destruction, fires, the emergence of extensive foci of chemical, biological, radiation contamination, mass deaths during combat operations, during public unrest, terrorist attack

Crowds of people in cities are fertile ground for the emergence of interpersonal and group conflicts, worsening the criminal situation, and increasing the danger to human life and health. The number of crimes, terrorist acts, and riots is growing year by year. The growth rate of crime in cities is 4 times faster than the growth rate of their population

Radical and sometimes painful reforms in almost all spheres of life have given rise to a number of phenomena in cities that are becoming serious criminogenic factors. Among them:

Economic instability;

Increase in unemployment rate;

Increasing stratification of the population by income level;

Changes at the level of state policy in ideological attitudes in

regarding property, means of production and psychological

the unwillingness of many people to accept these changes;

Power deficit;

The manifestation of bureaucracy and the spread of corruption in the state

apparatus.

This obviously explains the high growth rates crime in recent years and, in particular, increasing cases of mass antisocial manifestations, often accompanied by grave consequences (murder, bodily harm, arson, pogroms, destruction of property, disobedience to authorities).

A serious social irritant and criminogenic factor are refugees, which are mainly concentrated in cities. Many of them, unable to cope with difficulties, begin to earn a living through illegal means, engaging in theft, robbery, robbery, and often organizing criminal communities for these purposes.

It is in large cities that various informal youth associations– metalheads, punks, fans, rockers, skinheads. Under certain conditions, the listed groups of young people can pose a real danger to people around them, and this should be taken into account in everyday life. Informal associations are the main participants in the violation of public order in public places, that is, in mass riots. One type of mass disorder is mass pogroms involving violence, arson, destruction of property, the use of firearms, explosives or explosive devices with armed resistance to government officials.

Another kind - mass spectacles, also always carries an explosive danger. This applies to the greatest extent to rock music concerts, when the ecstasy of listeners, often pumped up on drugs, leads to sad consequences. Quite a large number of fans die in stadiums, despite the safety measures taken. Religious holidays are also often accompanied by human sacrifices. Potentially dangerous events also include demonstrations, political demonstrations, and national holidays.

The high degree of public danger for participants in mass spectacles is due to the fact of the existence of a large crowd of people that is difficult to control, facts of damage to property and harm to the health of citizens (and sometimes death), and disorganization of the activities of government and administrative bodies.

From the above we can conclude that any mass riots cause material and physical harm and disorganize the life of society.

The real threat to security in modern society has become terrorism. Terrorism in all its forms has become one of the most dangerous socio-political and moral problems in terms of scale, unpredictability and consequences. Basically, any form of terrorism threatens the safety of large cities and their population, entails huge political, economic and moral losses, exerting strong psychological pressure on people and claiming more and more lives of innocent citizens.

Chapter 3. Security system.

Having considered the sources of danger in a modern city, it is necessary to name the services that help people cope with emergency situations. Speaking about the city's security system, it is necessary to emphasize that there are city and regional services.

Security services in the city:

Fire protection service (fire protection)

Law enforcement service (police)

Health service (ambulance)

Gas service

the main task fire service– having discovered a fire, localize it, save people in trouble and, of course, put out the fire. Firefighters use fire engines for different purposes: main, special and auxiliary. Each fire truck is assigned a combat crew consisting of a commander, driver and firefighters. Combat crews on main and special vehicles are called a squad. A squad constructed by a tanker truck, pumper truck, or pumper truck is the primary tactical unit of the fire department. The latter is capable of independently performing tasks of extinguishing fires, rescuing people, protecting and evacuating material assets.

The police are called upon to ensure the protection of public order, personal and other property, rights and legitimate interests of citizens, enterprises, organizations and institutions from criminal attacks and other antisocial actions. The most important tasks of the police are the prevention and suppression of crimes and other antisocial actions, the rapid and complete detection of crimes, and all possible assistance in eliminating the causes that give rise to crimes and other offenses.

Ensuring the safety of vehicles and pedestrians on streets and roads. entrusted to the road patrol service (DPS). The activities of the traffic police are aimed at carrying out measures to prevent and reduce the severity of road injuries, suppression of offenses in the field of road safety and are built in accordance with the principles of legality, humanism, respect for human rights and transparency.

Among the main tasks of the traffic police:

Supervision of compliance with traffic rules;

Traffic regulation;

Participation in maintaining public order and fighting crime;

Carrying out emergency actions at the scene of a road traffic accident

incidents, providing assistance to victims and evacuating them to

medical institutions;

Transportation of damaged vehicles from the scene of an accident.

Emergency has a team of doctors of various specialties, well-trained support staff, and a fleet of maneuverable cars. The main task of this service is to provide medical assistance to the victim and, if necessary, transport him to the nearest medical facility. Modern medical equipment makes it possible to competently assess the condition of the injured person (patient) and help him in a timely manner.

The main task of the emergency gas service is to detect and eliminate gas leaks resulting from an emergency or associated with improper operation of gas equipment.

It is very important, in the event of an accident or dangerous situation, to correctly remember the procedure for calling the appropriate service:

1. Pick up the phone and dial the desired number.

2. Provide the reason for the call.

3. State your first and last name.

4. Inform where to arrive and phone number.

District utilities include: water supply, electricity supply, gasification system, road service. In addition, each district is divided into microdistricts, where the operational departments operate elevator services, services for electrical networks, heating networks and sewer networks. Ensuring life safety is a fairly broad concept; this system should also include the sanitary and epidemiological service, the water rescue service, and the regional headquarters for civil defense and emergency situations. The courts and the prosecutor's office stand guard over the honor and dignity of citizens, their property and housing inviolability.

Conclusion.

Thus, analyzing the role of the city in human life, we see that human life in a modern city is potentially dangerous. Even without being born, while in the womb, a person is exposed to constantly existing and active dangers of various types. And from the moment of birth, dangers threaten the life and health of city dwellers much more than those of rural residents. This is due to the fact that human activity aimed at transforming nature and creating a comfortable artificial habitat, such as a city, often causes unforeseen consequences. All human actions and all components of the urban environment (primarily technical means and technologies) have the ability to generate, along with positive properties and results, dangerous and harmful factors. In this case, a new positive result is usually accompanied by a new potential danger.

Therefore, ensuring safety in the conditions of a modern city is the main task for city residents, enterprises, organizations and institutions. The solution to the problem of ensuring life safety is to ensure normal (comfortable) conditions for people’s activities, to protect people and their environment (urban, residential, industrial) from the effects of harmful factors exceeding regulatory acceptable levels. We can say that the task of ensuring the safety of human life in the city as a living environment is not to eliminate existing dangers, but to reduce the potential level of dangers and reduce the consequences of their actions. Realized in space and time, the dangers of the city threaten not only the individual, but also one or another social group.

How to achieve safety? The first and most important way is to increase the awareness of the people. From childhood, parents are obliged to teach their child to behave correctly in dangerous situations on the street, in city transport, when communicating with strangers, interacting with dangerous objects and poisonous objects and toxic substances. Actively contribute to the formation of the foundations of environmental culture and a healthy lifestyle.

In secondary educational institutions, teachers should pay special attention to the formation in the minds of children and adolescents of a heightened sense of personal and collective safety, instilling skills in recognizing and assessing dangers, as well as safe behavior in emergency situations at home, at school, and on the street.

To prevent dangers and protect against them, to develop the appropriate worldview and behavior of people, the science of “Life Safety” is used. Its goal is to develop knowledge and skills to protect life and health in dangerous and emergency situations, to eliminate consequences and provide self- and mutual assistance in the event of danger; a conscious and responsible attitude towards issues of personal safety and the safety of others; the ability to recognize and evaluate dangerous and harmful factors in the human environment, and find ways to protect against them.

“Life Safety” provides general literacy in the field of safety, being an integral part of the preparation of a comprehensively developed individual.

Bibliography:

1. Life safety: Textbook for universities / L.A. Mikhailov, V.P. Solomin, A.L. Mikhailov, A.V. Starostenko et al. – St. Petersburg: Miter, ts007.

2. Life safety: Textbook. manual for universities / Ed. prof. L.A. Ant. – 2nd ed., revised. and additional – M.: UNITY – DANA, 2003.

3. Denisov V.V., Denisova I.A., Gutenev V.V., Montvila O.I. Life safety. Protection of the population and territories in emergency situations: Textbook. allowance. – Moscow: ICC “MarT”, Rostov n/a: Publishing Center “MarT”, 2003.

4. Mikryukov V.Yu. Life safety: Textbook / V.Yu. Mikryukov. Rostov n/d: Phoenix, 2006.

5. Novikov Yu.V. Ecology, environment and people: Proc. manual for universities, secondary schools and colleges. – 2nd ed., rev. and additional /Yu.V Novikov. – M.: FAIR PRESS, 2002.