How does road transport affect the environment? The impact of motor transport on the environment

For the full existence of society and transport support, a car is needed. Passenger flows are increasing in cities faster than the population. Transport has a negative impact on the natural environment due to emissions. The problem of pollution by vehicles remains relevant. Every day people breathe nitric oxide, carbon and hydrocarbons. The impact of cars on the ecological situation exceeds all permitted norms and standards.

The strong impact of transport on the environment is due to its great popularity. Almost everyone owns a car, so a lot of harmful substances are released into the air.

Composition of emissions

During the combustion of all kinds of substances, products are formed that enter the atmosphere. These include the following substances:

• carbon monoxide;
• hydrocarbons;
• sulfur dioxide;
• Nitric oxide;
• lead compounds;
• sulphuric acid.

The exhaust gases of cars contain hazardous substances - carcinogens that contribute to the development of cancer among mankind. Everything released by transport is highly toxic.

Water transport and its impact

Water vessels cannot be classified as environmentally friendly transport. Its negative impact is as follows:

• there is a deterioration of the biosphere due to waste emissions into the air during the operation of water transport;
• environmental disasters that occur during various accidents on ships associated with toxic products.

Harmful substances, penetrating into the atmosphere, return to the water along with precipitation.

On tankers, tanks are periodically washed to wash away the remains of the transported cargo. This contributes to water pollution. The impact of water transport on the environment is to reduce the level of existence of aquatic flora and fauna.

Air transport and its environmental damage

The impact of air transport on the environment also lies in the sounds emanating from it. The sound level on the airport platform is 100 dB, and in the building itself - 75 dB. Noise comes from engines, power plants, equipment of stationary objects. The pollution of nature lies in the electromagnetic relation. This is facilitated by radar and radio navigation, which is necessary in tracking the aircraft's route and weather conditions. Electromagnetic fields are created that threaten the health of mankind.

Air transport and the environment are closely linked. A significant amount of jet fuel combustion products are emitted into the air. Air transport has some features:

• kerosene used as fuel changes the structure of harmful substances;
• the degree of influence of harmful substances on nature is reduced due to the height of the transport flight.

Civil aviation emissions account for 75% of all engine gases.

With the help of rail transport, 80% of cargo transportation is carried out. Passenger turnover is 40%. The consumption of natural resources increases in accordance with the amount of work and, accordingly, more pollutants are released into the environment. But, comparing road and rail transport, there is less harm from the second.

This can be explained by the following reasons:

• the use of electric traction;
• less land use for railroads;
• low fuel consumption per unit of transport work.

The impact of trains on nature is the pollution of air, water and land during the construction and use of railways. Contaminated water sources are formed in the places of washing and preparation of wagons. Remains of cargo, mineral and organic substances, salts and various bacterial pollutants get into water bodies. There is no water supply at the preparatory points of the wagons, so there is an intensive use of natural waters.

Road transport and its impact

The damage caused by traffic is inevitable. How can we solve the problem of pollution of cities by road transport. Environmental problems can be solved only by complex actions.

Basic problem solving methods:

• using refined fuel instead of cheap gasoline that contains hazardous substances;
• use of alternative energy sources;
• creation of a new type of engines;
• correct operation of the vehicle.

In most Russian cities, residents hold an action on September 22 called "Day without a car." On this day, people give up their cars and try to get around in other ways.

Consequences of harmful influence

Briefly about the impact of transport on the environment and rather severe consequences:

1. The greenhouse effect. Due to the penetration of exhaust gases into the atmosphere, its density increases and a greenhouse effect is created. The surface of the earth is heated by solar heat, which then cannot return to space. Because of this problem, the level of the world ocean is rising, the glaciers are beginning to melt, and the flora and fauna of the Earth are suffering. The additional heat causes an increase in rainfall in the tropics. In areas of drought, on the contrary, it becomes even less rainy. The temperature of the seas and oceans will gradually rise, and lead to flooding of low-lying parts of the earth
2. Environmental problems. The widespread use of automobiles leads to air, water and atmosphere pollution. All this leads to a deterioration in human health.
3. Acid rain occurs due to the influence of exhaust gas. Under their influence, the soil composition changes, water bodies are polluted, and human health suffers.
4. Ecosystem changes. All life on the planet Earth suffers from exhaust gases. In animals, due to the inhalation of gases, the work of the respiratory system worsens. Due to the development of hypoxia, a violation occurs in the work of other organs. Due to the stress experienced, reproduction is reduced, which leads to the extinction of some species of animals. Among the representatives of the flora, disturbances also occur during natural respiration.

The ecology of transport determines the scale of the impact on nature. Scientists are developing entire systems of conservation strategies. They are trying to create promising directions for the greening of transport.

People use water, air, road and rail transport. Each of them has its own advantages, and all of them cause serious harm to the environment. Therefore, work on reducing the emission of harmful substances is an urgent problem. Work is underway to develop alternative modes of transportation. For the earth's ecosystem, the main danger is oil and oil products. Man, not noticing this, he causes global harm to nature. Under the influence of harmful substances, the ecosystem is destroyed, animal and plant species disappear, mutations develop, etc. All this is reflected in the existence of mankind. It is important to develop alternative types of vehicles and fuels.

The abstract was completed by a student Sulatskaya E.

Rostov State Economic University "RINH"

Department of Reg. Economics and nature management

Rostov-on-Don

Against nature by car. Aviation and rocket carriers. Environmental pollution by ships. Declaration and Pan-European Program for Transport, Environment and Health.

Introduction

The transport complex, in particular in Russia, which includes road, sea, inland waterway, rail and air transport, is one of the largest pollutants of the atmospheric air; its impact on the environment is expressed mainly in the emissions of toxicants into the atmosphere with exhaust gases engines and harmful substances from stationary sources, as well as pollution of surface water bodies, the formation of solid waste and the impact of traffic noise.

The main sources of environmental pollution and consumers of energy resources include road transport and the infrastructure of the motor transport complex.

Air pollutant emissions from cars are more than an order of magnitude larger than emissions from rail vehicles. Next come (in descending order) air transport, maritime and inland water transport. The non-compliance of vehicles with environmental requirements, the continued increase in traffic flows, the poor condition of roads - all this leads to a constant deterioration of the environmental situation.

Since motor transport, in comparison with other modes of transport, brings the greatest harm to the environment, I would like to dwell on it in more detail.

Against nature by car

The idea that something needs to be done with vehicles is spinning in the head of every conscious person. The terrible level of air pollution, in terms of the amount of harmful gases, MPC, for example, in Moscow is 30 times higher than the maximum allowable rate.

Life in the cities has become unbearable. Tokyo, Paris, London, Mexico City, Athens… suffocate with an excess of cars. In Moscow, more than 100 days a year smog. Why? No one wants to understand that the energy consumed by road transport exceeds by many times all environmental standards. Much has been said and written about this, but the issue remains unresolved, since no one has delved into the essence of the problem. And therefore, motor transport is the most energetically unfavorable.

Excess air from car exhaust caused a European flood in the summer of 2002: a flood in Germany, Czechoslovakia, France, Italy, the Krasnodar Territory, Adygea. Drought and smog in the central regions of the European part of Russia, in the Moscow region. The flood can be explained by the fact that powerful streams of hot air from automobile CO2 exhaust and H2O exhaust gases from Central and Eastern Europe, where the growth in the number of cars exceeded all permissible norms, were added to atmospheric currents and fluctuations in air flows. The number of cars on highways and cities has increased by 5 times. from this, the thermal heating of the air and its volume from automobile exhaust vapors sharply increased. If in the 1970s the heating of the atmosphere by road transport was much less than the heating of the Earth's surface from the sun, then in 2002 the number of moving cars increased so much that the heating of the atmosphere from cars becomes commensurate with the heating from the sun and sharply disrupts the climate of the atmosphere. Heated CO2 and H2O vapor from car exhaust give an excess of air mass in the center of Russia, equivalent to air flows from the Gulf Stream, and all this excess heated air increases atmospheric pressure. And when the wind blows towards Europe, two currents from the Atlantic Ocean and from Russia collide here, producing such excess rainfall that leads to the European flood.

The amount of harmful substances entering the atmosphere, as part of the exhaust gases, depends on the general technical condition of the vehicles and especially on the engine - the source of the greatest pollution. So, if the carburetor adjustment is violated, CO emissions increase by 4 to 5 times.

The use of leaded gasoline, which has lead compounds in its composition, causes air pollution with very toxic lead compounds. About 70% of the lead added to gasoline with ethyl liquid enters the atmosphere with exhaust gases, of which 30% settles on the ground immediately, and 40% remains in the atmosphere. One medium-duty truck emits 2.5 - 3 kg of lead per year. The concentration of lead in the air depends on the lead content in gasoline:

Lead concentration in air, µg/m 3 …..0.40 0.50 0.55 1.00

The share of road transport in air pollution in large cities of the world is, %:

Carbon monoxide Nitrogen oxides Hydrocarbons

Moscow 96.3 32.6 64.4

St. Petersburg 88.1 31.7 79

Tokyo 99 33 95

New York 97 31 63

In some cities, CO concentration reaches 200 mg/m 3 or more for short periods, with standard values ​​of the maximum allowable one-time concentrations of 40 mg/m 3 (USA) and 10 mg/m 3 (Russia).

In the Moscow region, exhaust gas (car exhaust gases) CO, CH, CnHm - create smog, and high pressure leads to the fact that the smoke of burning peat bogs spreads along the ground, does not go up, is added to exhaust gas, as a result, MPC is hundreds of times higher than the permissible norm .

This leads to the development of a wide range of diseases (bronchitis, pneumonia, bronchial asthma, heart failure, strokes, stomach ulcers, through which these gases are released ...) and an increase in the mortality of people with weakened immune systems. It is especially difficult for children6 to suffer from bronchitis, bronchial asthma, cough, in newborns, a violation of the gene structures of the body and incurable diseases, as a result, an increase in child mortality by 10% per year.

In healthy people, the body copes with poisoned air, but it takes so much physiological strength that as a result all these people lose their ability to work, labor productivity drops, and the brain works very poorly.

To reduce slip when driving cars in winter, salt is sprinkled on the streets, creating incredible mud and puddles. This dirt and dampness is transferred to trolleybuses and buses, to the subway and transitions, entrances and apartments, shoes deteriorate from this, salinization of the soil and rivers kills all living things, destroys trees and grasses, fish and all aquatic animals - the ecology is destroyed.

In Russia, 1 km of roads accounts for 2 to 7 hectares. At the same time, not only agricultural, forest and other lands are withdrawn, but the territory is also divided into separate closed areas, which disrupts the habitats of wild animal populations.

About 2 billion tons of oil is consumed by road and diesel transport, cars, tractors, ships, combines, tanks, aircraft.

Isn't it crazy to throw 2 billion tons of oil into the wind and use only 39 million tons to transport goods. At the same time, for example, in the United States, oil will run out in 10 years, in 20 years there will be a military reserve, in 30 years black gold will cost more than yellow.

If you do not change the consumption of oil, then in 40 years there will not be a drop left. Without oil, civilization will perish before reaching the age of maturity, the ability to revive civilization elsewhere.

Measures taken in Russia to reduce the negative impact of vehicles on the environment:

Measures are being taken to improve the quality of domestic automotive fuel: the production of high-octane gasoline by Russian refineries is growing, and the production of environmentally cleaner gasoline at JSC Moscow Oil Refinery has been organized. However, imports of leaded gasolines remain. As a result, less lead is released into the atmosphere from vehicles.

The existing legislation does not allow limiting the import into the country of old cars with low performance characteristics, and the number of foreign cars with a long service life that do not meet state standards.

Control over compliance with environmental requirements in the operation of vehicles is carried out by the regional departments of the Russian Transport Inspectorate of the Ministry of Transport in close cooperation with the State Committee for Ecology of Russia. In the course of the large-scale operation “Clean Air”, in which all departments of the Russian Transport Inspectorate took part, it was found that in almost all regions of the Russian Federation the share of cars operated in excess of the current toxicity standards and in some regions reaches 40%. At the suggestion of the departments of the Russian Transport Inspectorate, toxicity coupons for cars have been introduced in most territories of the constituent entities of the Russian Federation.

In recent years, despite the growth in the number of cars, there has been a tendency in Moscow to stabilize the volume of emissions of harmful substances. The main factors supporting this situation are the introduction of catholic exhaust gas converters; introduction of mandatory environmental certification of vehicles owned by legal entities; a significant improvement in fuel at gas stations.

In order to reduce environmental pollution, the transition of road facilities from liquid fuel to gas continues. Measures are being taken to improve the environmental situation in the areas where asphalt concrete plants and asphalt mixing plants are located, cleaning equipment is being modernized, and oil burners are being improved.

Aviation and rocket carriers

The use of gas turbine propulsion systems in aviation and rocketry is truly enormous. All rocket carriers and all aircraft (except propeller-driven aircraft) use the thrust of these installations. Exhaust gases of gas turbine propulsion systems (GTE) contain such toxic components as CO, NOx, hydrocarbons, soot, aldehydes, etc.

Studies of the composition of combustion products of engines installed on Boeing-747 aircraft showed that the content of toxic components in combustion products significantly depends on the engine operating mode.

High concentrations of CO and CnHm (n is the nominal number of engine revolutions) are typical for gas turbine engines in reduced modes (idling, taxiing, approaching the airport, landing approach), while the content of nitrogen oxides NOx (NO, NO2, N2O5) increases significantly at work in modes close to nominal (takeoff, climb, flight mode).

The total emission of toxic substances by aircraft with gas turbine engines is constantly growing, which is due to an increase in fuel consumption up to 20–30 t/h and a steady increase in the number of aircraft in operation.

Gas turbine emissions have the greatest impact on living conditions at airports and areas adjacent to test stations. Comparative data on emissions of harmful substances at airports show that the receipts from gas turbine engines into the surface layer of the atmosphere are:

Carbon oxides - 55%

Nitrogen oxides - 77%

Hydrocarbons - 93%

Aerosol - 97

the remaining emissions come from ground vehicles with internal combustion engines.

Air pollution by vehicles with rocket propulsion systems occurs mainly during their operation before launch, during takeoff and landing, during ground tests during their production and after repair, during storage and transportation of fuel, as well as during refueling of aircraft. The operation of a liquid rocket engine is accompanied by the release of products of complete and incomplete combustion of fuel, consisting of O, NOx, OH, etc.

During the combustion of solid fuels, H 2 O, CO 2 , HCl, CO, NO, Cl, as well as solid particles of Al 2 O 3 with an average size of 0.1 μm (sometimes up to 10 μm) are emitted from the combustion chamber.

Space Shuttle engines burn both liquid and solid propellants. As the ship moves away from the Earth, the products of fuel combustion penetrate into various layers of the atmosphere, but mostly into the troposphere.

Under launch conditions, a cloud of combustion products, water vapor from the noise suppression system, sand and dust form at the launch system. The volume of combustion products can be determined from the time (usually 20 s) of operation of the facility on the launch pad and in the surface layer. After launch, the high-temperature cloud rises to a height of up to 3 km and moves under the influence of the wind to a distance of 30-60 km, it can dissipate, but can also cause acid rain.

During launch and return to Earth, rocket engines adversely affect not only the surface layer of the atmosphere, but also outer space, destroying the Earth's ozone layer. The scale of the destruction of the ozone layer is determined by the number of launches of rocket systems and the intensity of flights of supersonic aircraft. During the 40 years of the existence of cosmonautics in the USSR and later in Russia, more than 1,800 launches of carrier rockets have been carried out. According to the forecasts of the company Aerospace in the XXI century. to transport cargo into orbit, up to 10 rocket launches per day will be carried out, while the emission of combustion products of each rocket will exceed 1.5 t/s.

According to GOST 17.2.1.01 - 76 emissions into the atmosphere are classified:

according to the state of aggregation of harmful substances in emissions, these are gaseous and vaporous (SO 2 , CO, NO x hydrocarbons, etc.); liquid (acids, alkalis, organic compounds, solutions of salts and liquid metals); solid (lead and its compounds, organic and inorganic dust, soot, resinous substances, etc.);

by mass emission, distinguishing six groups, t/day:

less than 0.01 incl.;

over 0.01 to 0.1 incl.;

over 0.1 to 1.0 incl.;

over 1.0 to 10 incl.;

over 10 to 100 incl.;

In connection with the development of aviation and rocket technology, as well as the intensive use of aircraft and rocket engines in other sectors of the national economy, their total emission of harmful impurities into the atmosphere has increased significantly. However, these engines still account for no more than 5% of toxic substances entering the atmosphere from vehicles of all types.

Ship pollution

The marine fleet is a significant source of air pollution and the world's oceans. The stringent requirements of the International Maritime Organization (IMO) of 1997 on the quality control of marine diesel exhaust gases and bilge, domestic and sewage discharged overboard are aimed at limiting the negative impact of ships in operation on the environment.

In order to reduce gas pollution during diesel operation with metals, soot and other solid impurities, diesel engines and shipbuilders are forced to equip ship power plants and propulsion complexes with exhaust gas cleaning equipment, more efficient separators of oily bilge water, sewage and domestic water purifiers, modern incinerators.

Refrigerators, tankers, gas and chemical carriers, and some other ships are sources of air pollution with freons (nitrogen oxides0 used as a working fluid in refrigeration plants. Freons destroy the ozone layer of the Earth's atmosphere, which is a protective shield for all living things from the cruel radiation of ultraviolet radiation.

Obviously, the heavier the fuel used for thermal engines, the more heavy metals it contains. In this regard, the use of natural gas and hydrogen, the most environmentally friendly types of fuel, on ships is very promising. The exhaust gases of diesel engines running on gas fuel practically do not contain solid substances (soot, dust), as well as sulfur oxides, contain much less carbon monoxide and unburned hydrocarbons.

Sulfuric gas SO2, which is part of the exhaust gases, oxidizes to the state of SO3, dissolves in water and forms sulfuric acid, and therefore the degree of harmfulness of SO2 to the environment is twice as high as that of nitrogen oxides NO2, these gases and acids disrupt the ecological balance.

If we take as 100% all the damage from the operation of transport ships, then, as analysis shows, the economic damage from pollution of the marine environment and the biosphere is on average 405%, from vibration and noise of equipment and the ship's hull - 22%, from corrosion of equipment and the hull -18 %, from the unreliability of transport engines -15%, from the deterioration of the health of the crew -5%.

IMO rules from 1997 limit the maximum sulfur content in fuel to 4.5%, and in limited water areas (for example, in the Baltic region) to 1.5%. As for nitrogen oxides Nox, for all new ships under construction, the limit norms for their content in exhaust gases are set depending on the speed of the crankshaft of the diesel engine, which reduces atmospheric pollution by 305. At the same time, the value of the upper limit of the content of Nox, for low-speed diesel engines, is higher, than medium and high-speed ones, since they have more time to burn fuel in the cylinders.

As a result of the analysis of all the negative factors affecting the environment during the operation of transport ships, it is possible to formulate the main measures aimed at reducing this impact:

the use of higher quality grades of motor fuels, as well as natural gas and hydrogen as an alternative fuel;

optimization of the working process in a diesel engine in all operating modes with the widespread introduction of electronically controlled fuel injection systems and control of the valve timing and fuel supply, as well as optimization of the oil supply to the diesel cylinders;

complete prevention of fires in utilization boilers by equipping them with temperature control systems in the boiler cavity, fire extinguishing, soot blowing;

obligatory equipment of ships with technical means for quality control of exhaust gases escaping into the atmosphere and oily, waste and domestic waters removed overboard;

complete prohibition of the use of nitrogen-containing substances on ships for any purpose (in refrigeration plants, fire fighting systems, etc.)

prevention of leaks in omental and flange connections and ship systems.

efficient use of shaft-generator units as part of ship power systems and the transition to the operation of diesel generators with variable speed.

Thus, it cannot be said that no attention is paid to the issue of transport pollution. More and more conventional trains are being replaced by electric locomotives, battery-powered cars are being developed and are already being produced, with the current pace of progress, one can hope that environmentally friendly aircraft and rocket engines will soon appear. Governments make decisions against pollution of the planet. This is evidenced by the adopted declaration.

Conclusion

The protection of nature is the task of our century, a problem that has become a social one. Again and again we hear about the danger threatening the environment, but still many of us consider them an unpleasant, but inevitable product of civilization and believe that we will still have time to cope with all the difficulties that have come to light.

However, human impact on the environment has taken on alarming proportions. To fundamentally improve the situation, purposeful and thoughtful actions will be needed. A responsible and efficient policy towards the environment will be possible only if we accumulate reliable data on the current state of the environment, substantiated knowledge about the interaction of important environmental factors, if we develop new methods to reduce and prevent the harm caused to Nature by Man.

Appendix

Oil reserves

Bibliography

Journal Nature and Man. No. 8 2003 ed.: Science Moscow 2000

Marine Fleet Magazine No. 11-12 2000 edition: RIC

Magazine Conversion in mechanical engineering No. 1 2001 ed.: Moscow "Infraconversion."

Journal Energy: economics, technology. Ecology. No. 11 1999 edition: Nauka Moscow 1999

Magazine "EcoNews" № 5 2002 www.statsoft.ru

Information portal on transport and customs statistics www.logistic.ru

Modern society cannot do without transport. Now both cargo and public vehicles are used, which are supplied with various types of energy to ensure movement. At the moment, the following vehicles are used in different parts of the world:

• automobile (buses, cars, minibuses);
• railway (metro, trains, electric trains);
• water (boats, boats, container ships, tankers, ferries, cruise ships);
• air (airplanes, helicopters);
• electric transport (trams, trolleybuses).

Despite the fact that transport allows you to speed up the time of all movements of people not only on the surface of the earth, but also through air and water, various vehicles have an impact on the environment.

Environmental pollution

Each mode of transport pollutes the environment, but a significant advantage - 85% of the pollution is carried out by road transport, which emits exhaust gases. Cars, buses and other vehicles of this type lead to various problems:

• air pollution;
• deterioration in human and animal health.

Sea transport

Maritime transport pollutes the hydrosphere most of all, since dirty ballast water and water used to wash sailing ships enter the reservoirs. Power plants of ships pollute the air with various gases. If tankers carry oil products, then there is a risk of water pollution with oil.

Air transport

Air transport pollutes, first of all, the atmosphere. Their source is aircraft engine gases. Thanks to the operation of air transport, carbon dioxide and nitrogen oxides, water vapor and sulfur oxides, carbon oxides and particulate matter enter the air.

Electric transport

Electric transport contributes to environmental pollution through electromagnetic radiation, noise and vibration. During its maintenance, various harmful substances enter the biosphere.

Thus, during the operation of a variety of vehicles, environmental pollution occurs. Harmful substances pollute water, soil, but most pollutants enter the atmosphere. These are carbon monoxide, oxides, heavy compounds and vaporous substances. As a result of this, not only the greenhouse effect occurs, but also fall out, the number of diseases increases and the state of people's health worsens.

Interaction of transport objects with the environment

Transport is one of the main sources of air pollution in the atmosphere. Environmental problems associated with the impact of various transport facilities on the environment are determined by the amount of emissions of toxicants by engines, and also consist in the pollution of water bodies. Solid waste generation and noise pollution contribute their share of negative impacts. At the same time, it is road transport that ranks first as an environmental pollutant and consumer of energy resources. An order of magnitude lower is the negative effect of railway transport facilities. Pollution - in decreasing order - from air, sea and inland water transport is even less.

Impact of road transport on the environment

By burning a huge amount of petroleum products, cars harm both the environment (primarily the atmosphere) and human health. The air is depleted of oxygen, saturated with harmful substances of exhaust gases, the amount of dust suspended in the atmosphere and settled on the surface of various substrates increases.

Wastewater from the enterprises of the motor transport complex is usually saturated with oil products and suspended solids, and surface runoff from the roadway contains additional heavy metals (lead, cadmium, etc.) and chlorides.

Cars are also intensive factors in the elimination of vertebrates and invertebrates, they are also dangerous for humans, causing many deaths and severe injuries.

Remark 1

Owners of personal vehicles often wash their cars on the banks of water bodies using synthetic detergents that enter the water.

Damage to natural ecosystems is caused by the chemical method of eliminating snow and ice from road surfaces with the help of reagents - chloride compounds (through direct contact and through the soil).

The dangerous effect of these salts is manifested in the process of corrosion of the metal that is part of the car, the destruction of road machines and structural elements of road signs and roadside barriers.

Example 1

The share of cars operated, despite the excess of modern standards for toxicity and opacity of emissions, averages 20 - 25%.

The local geo-ecological impact of transport is manifested in the intensive accumulation of carbon monoxide, nitrogen oxides, hydrocarbons or lead in the vicinity of pollution sources (along highways, main streets, in tunnels, at intersections). Part of the pollutants is transported from the place of emission, causing regional geoecological impacts. Carbon dioxide and other gases that have a greenhouse effect, spreading throughout the atmosphere, causing global geoecological impacts that are unfavorable for humans.

Example 2

Approximately 15% of the samples in the areas affected by transport exceeded the MPCs of heavy metals hazardous to health.

The main motor transport wastes are batteries (lead), interior upholstery elements (plastic), car tires, fragments of car bodies (steel).

Influence of rail transport

The main source of air pollution is exhaust gases emitted by diesel locomotives containing carbon monoxide, nitrogen oxides, various types of hydrocarbons, sulfur dioxide, and soot.

In addition, up to 200 m³ of wastewater containing pathogenic microorganisms per year from passenger cars per kilometer of track, in addition, up to 12 tons of dry garbage are thrown out.

In the process of washing the rolling stock, detergents are thrown into the water along with wastewater - synthetic surfactants, various petroleum products, phenols, hexavalent chromium, acids, alkalis, various organics and inorganic suspended solids.

Noise pollution from moving trains causes negative health effects and generally affects the quality of life of the population.

Impact of air transport

Air transport saturates the atmosphere with carbon monoxide, hydrocarbons, nitrogen oxides, soot, and aldehydes. The engines of aviation and rocket transport objects have a negative effect on the troposphere, stratosphere, and outer space. Emissions that contribute to the destruction of the planet's ozone layer account for about 5% of toxic substances entering the atmosphere from the entire transport sector.

Fleet impact

The river and, in particular, the marine fleet seriously pollutes the atmosphere and hydrosphere. Transport shipping saturates the atmosphere with freons, which destroy the ozone layer of the Earth's atmosphere, and the fuel emits oxides of sulfur, nitrogen, and carbon monoxide during combustion. It is known that 40% of the negative impacts of water transport are due to air pollution. 60% “share” among themselves noise pollution, vibrations unusual for the biosphere, solid waste and corrosion processes of transport facilities, oil spills during tanker accidents and some other things. Mortality of juvenile fish and many other hydrobionts is associated with waves occurring during the operation of sea vessels.

Road transport is the most aggressive in comparison with other modes of transport in relation to the environment. It is a powerful source of its chemical (supplies a huge amount of toxic substances into the environment), noise and mechanical pollution. It should be emphasized that with the increase in the car park, the level of the harmful impact of vehicles on the environment increases intensively. So, if in the early 1970s, hygienists determined the share of pollution introduced into the atmosphere by road transport, on average, equal to 13%, now it has already reached 50% and continues to grow. And for cities and industrial centers, the share of vehicles in the total volume of pollution is much higher and reaches 70% or more, which creates a serious environmental problem that accompanies urbanization.

There are several sources of toxic substances in cars, the main ones are three:

• exhaust gases
• crankcase gases
• fuel vapors

Rice. Sources of toxic emissions

The largest share of chemical pollution of the environment by road transport is accounted for by the exhaust gases of internal combustion engines.

Theoretically, it is assumed that during the complete combustion of fuel, as a result of the interaction of carbon and hydrogen (which are part of the fuel) with atmospheric oxygen, carbon dioxide and water vapor are formed. In this case, the oxidation reactions have the form:

С+О2=СО2,
2H2+O2=2H2.

In practice, due to the physical and mechanical processes in the engine cylinders, the actual composition of the exhaust gases is very complex and includes more than 200 components, a significant part of which are toxic.

Table. Approximate composition of exhaust gases of automobile engines

The composition of the exhaust gases of engines using the example of passenger cars without their neutralization can be represented in the form of a diagram.

Rice. Components of exhaust gases without the use of neutralization

As can be seen from the table and figure, the composition of the exhaust gases of the considered types of engines differs significantly, primarily in the concentration of products of incomplete combustion - carbon monoxide, hydrocarbons, nitrogen oxides and soot.

Toxic components of exhaust gases include:

• carbon monoxide
• hydrocarbons
• nitrogen oxides
• sulfur oxides
• aldehydes
• benzo(a)pyrene
• lead compounds

The difference in the composition of the exhaust gases of gasoline and diesel engines is explained by the large excess air coefficient α (the ratio of the actual amount of air entering the engine cylinders to the amount of air theoretically required for combustion of 1 kg of fuel) for diesel engines and better fuel atomization (fuel injection). In addition, in a gasoline carburetor engine, the mixture for different cylinders is not the same: for cylinders located closer to the carburetor it is rich, and for those farther from it it is poorer, which is a disadvantage of gasoline carburetor engines. Part of the air-fuel mixture in carburetor engines enters the cylinders not in a vapor state, but in the form of a film, which also increases the content of toxic substances due to poor combustion of the fuel. This disadvantage is not typical for gasoline engines with fuel injection, since the fuel is supplied directly to the intake valves.

The reason for the formation of carbon monoxide and partially hydrocarbons is the incomplete combustion of carbon (the mass fraction of which in gasoline reaches 85%) due to an insufficient amount of oxygen. Therefore, the concentrations of carbon monoxide and hydrocarbons in the exhaust gases increase with the enrichment of the mixture (α 1, the probability of these transformations in the flame front is small and the exhaust gases contain less CO, but there are additional sources of its occurrence in the cylinders:

• low-temperature sections of the flame of the fuel ignition stage
• fuel droplets entering the chamber at the late stages of injection and burning in a diffusion flame with a lack of oxygen
• soot particles formed during the propagation of a turbulent flame along a heterogeneous charge, in which, with a general excess of oxygen, zones with its deficiency can be created and reactions of the type can be carried out:

2С+О2 → 2СО.

Carbon dioxide CO2 is a non-toxic, but harmful substance due to the recorded increase in its concentration in the planet's atmosphere and its impact on climate change. The main share of CO formed in the combustion chamber is oxidized to CO2 without leaving the chamber, because the measured volume fraction of carbon dioxide in the exhaust gases is 10-15%, i.e. 300 ... 450 times more than in atmospheric air. The irreversible reaction makes the greatest contribution to the formation of CO2:

CO + OH → CO2 + H

Oxidation of CO to CO2 occurs in the exhaust pipe, as well as in the exhaust gas converters that are installed on modern cars for the forced oxidation of CO and unburned hydrocarbons to CO2 due to the need to comply with toxicity standards.

hydrocarbons

Hydrocarbons - numerous compounds of various types (for example, C6H6 or C8H18) consist of the original or decayed fuel molecules, and their content increases not only with enrichment, but also with depletion of the mixture (a > 1.15), which is explained by an increased amount of unreacted (unburned) ) fuel due to excess air and misfires in individual cylinders. The formation of hydrocarbons also occurs due to the fact that at the walls of the combustion chamber the temperature of the gases is not high enough to burn the fuel, so the flame is extinguished here and complete combustion does not occur. The most toxic polycyclic aromatic hydrocarbons.

In diesel engines, light gaseous hydrocarbons are formed during thermal decomposition of fuel in the flame failure zone, in the core and in the leading front of the flame, on the wall on the walls of the combustion chamber and as a result of secondary injection (post-injection).

Solid particles include insoluble (solid carbon, metal oxides, silicon dioxide, sulfates, nitrates, asphalts, lead compounds) and soluble in an organic solvent (resins, phenols, aldehydes, varnish, carbon deposits, heavy fractions contained in fuel and oil) substances.

Solid particles in the exhaust gases of supercharged diesel engines consist of 68 ... 75% of insoluble substances, 25 ... 32% of soluble substances.

Soot

Soot (solid carbon) is the main component of insoluble particulate matter. It is formed during bulk pyrolysis (thermal decomposition of hydrocarbons in the gas or vapor phase with a lack of oxygen). The mechanism of soot formation includes several stages:

• nucleation
• growth of nuclei to primary particles (hexagonal plates of graphite)
• increase in particle size (coagulation) to complex formations - conglomerates, including 100 ... 150 carbon atoms
• burnout

The release of soot from the flame occurs at α = 0.33…0.70. In tuned engines with external carburetion and spark ignition (petrol, gas), the likelihood of such zones is negligible. In diesel engines, local zones oversaturated with fuel are formed more often and the listed processes of soot formation are fully realized. Therefore, soot emissions from the exhaust gases of diesel engines are greater than those of spark ignition engines. The formation of soot depends on the properties of the fuel: the greater the C/H ratio in the fuel, the higher the soot yield.

The composition of solid particles, in addition to soot, includes compounds of sulfur and lead. Nitrogen oxides NOx represent a set of the following compounds: N2O, NO, N2O3, NO2, N2O4 and N2O5. In the exhaust gases of automobile engines, NO prevails (99% in gasoline engines and more than 90% in diesel engines). In the combustion chamber, NO can form:

• at high-temperature air nitrogen oxidation (thermal NO)
• as a result of low-temperature oxidation of nitrogen-containing fuel compounds (fuel NO)
• due to the collision of hydrocarbon radicals with nitrogen molecules in the combustion reaction zone in the presence of temperature pulsation (fast NO)

The combustion chambers are dominated by thermal NO formed from molecular nitrogen during the combustion of a lean air-fuel mixture and a mixture close to stoichiometric behind the flame front in the zone of combustion products. Predominantly during the combustion of lean and moderately rich mixtures (α > 0.8), reactions occur according to a chain mechanism:

O + N2 → NO + N
N + O2 → NO + O
N+OH → NO+H.

In rich mixtures< 0,8) осуществляются также реакции:

N2 + OH → NO + NH
NH + O → NO + OH.

In lean mixtures, the NO output is determined by the maximum temperature of the chain-thermal explosion (maximum temperature 2800 ... 2900 ° K), i.e., the kinetics of formation. In rich mixtures, the NO yield ceases to depend on the maximum explosion temperature and is determined by the decomposition kinetics, and the NO content decreases. When burning lean mixtures, the formation of NO is significantly affected by the uneven temperature field in the zone of combustion products and the presence of water vapor, which is an inhibitor in the NOx oxidation chain reaction.

The high intensity of the process of heating and then cooling the mixture of gases in the ICE cylinder leads to the formation of significantly nonequilibrium concentrations of the reactants. There is a freezing (hardening) of the formed NO at the level of maximum concentration, which is found in the exhaust gases due to a sharp slowdown in the rate of decomposition of NO.

The main lead compounds in vehicle exhaust gases are chlorides and bromides, as well as (in smaller amounts) oxides, sulfates, fluorides, phosphates and some of their intermediate compounds, which are in the form of aerosols or solid particles at temperatures below 370 ° C. About 50% of lead remains in the form of soot on engine parts and in the exhaust pipe, the rest goes into the atmosphere with exhaust gases.

A large number of lead compounds are released into the air when this metal is used as an antiknock agent. Currently, lead compounds are not used as antiknock agents.

Sulfur oxides

Sulfur oxides are formed during the combustion of sulfur contained in the fuel by a mechanism similar to the formation of CO.

The concentration of toxic components in exhaust gases is estimated in volume percent, ppm by volume - ppm -1, (parts per million, 10,000 ppm = 1% by volume) and less often in milligrams per 1 liter of exhaust gases.

In addition to exhaust gases, sources of environmental pollution by cars with carburetor engines are crankcase gases (in the absence of closed crankcase ventilation, as well as evaporation of fuel from the fuel system.

The pressure in the crankcase of a gasoline engine, with the exception of the intake stroke, is much less than in the cylinders, so part of the air-fuel mixture and exhaust gases break through leaks in the cylinder-piston group from the combustion chamber into the crankcase. Here they mix with oil and fuel vapors washed off the cylinder walls of a cold engine. Crankcase gases dilute the oil, contribute to water condensation, aging and contamination of the oil, and increase its acidity.

In a diesel engine, during the compression stroke, clean air breaks into the crankcase, and during combustion and expansion, exhaust gases with concentrations of toxic substances proportional to their concentrations in the cylinder. In diesel crankcase gases, the main toxic components are nitrogen oxides (45 ... 80%) and aldehydes (up to 30%). The maximum toxicity of crankcase gases of diesel engines is 10 times lower than that of exhaust gases, therefore the proportion of crankcase gases in a diesel engine does not exceed 0.2 ... 0.3% of the total emission of toxic substances. Given this, forced crankcase ventilation is usually not used in automotive diesel engines.

The main sources of fuel vapors are the fuel tank and the power system. Higher engine compartment temperatures, due to more loaded engine operating modes and the relative crampedness of the vehicle's engine compartment, cause significant fuel evaporation from the fuel system when a hot engine is stopped. Given the large emission of hydrocarbon compounds as a result of fuel evaporation, all car manufacturers are currently using special systems for their capture.

In addition to hydrocarbons coming from the car fuel system, significant atmospheric pollution with volatile hydrocarbons of car fuel occurs when cars are refueled (on average, 1.4 g of CH per 1 liter of fuel being poured). Evaporation also causes physical changes in the gasolines themselves: due to a change in the fractional composition, their density increases, starting qualities deteriorate, and the octane number of thermal cracking and direct distillation gasolines decreases. In diesel vehicles, fuel evaporation is practically absent due to the low volatility of diesel fuel and the tightness of the diesel fuel system.

The level of air pollution is assessed by comparing the measured and the maximum allowable concentration (MAC). MPC values ​​are set for various toxic substances with constant, average daily and one-time actions. The table shows the average daily MPC values ​​for some toxic substances.

Table. Permissible concentrations of toxic substances

According to research, a passenger car with an average annual mileage of 15 thousand km "inhales" 4.35 tons of oxygen and "exhales" 3.25 tons of carbon dioxide, 0.8 tons of carbon monoxide, 0.2 tons of hydrocarbons, 0.04 tons of oxides nitrogen. Unlike industrial enterprises, the emission of which is concentrated in a certain zone, a car disperses the products of incomplete combustion of fuel throughout almost the entire territory of cities, and directly in the surface layer of the atmosphere.

The share of pollution by cars in large cities reaches large values.

Table. The share of road transport in the total air pollution in the largest cities of the world, %

Toxic components of exhaust gases and fumes from the fuel system adversely affect the human body. The degree of exposure depends on their concentrations in the atmosphere, the state of the person and his individual characteristics.

carbon monoxide

Carbon monoxide (CO) is a colorless, odorless gas. The density of CO is less than air, and therefore it can easily spread in the atmosphere. Entering the human body with inhaled air, CO reduces the function of oxygen supply, displacing oxygen from the blood. This is due to the fact that the absorption of CO by the blood is 240 times higher than the absorption of oxygen. CO has a direct effect on tissue biochemical processes, resulting in a violation of fat and carbohydrate metabolism, vitamin balance, etc. As a result of oxygen starvation, the toxic effect of CO is associated with a direct effect on the cells of the central nervous system. An increase in the concentration of carbon monoxide is also dangerous because, as a result of oxygen starvation of the body, attention is weakened, the reaction slows down, the efficiency of drivers decreases, which affects road safety.

The nature of the toxic effects of CO can be traced from the diagram shown in the figure.

Rice. Diagram of the effects of CO on the human body:
1 - death; 2 - mortal danger; 3 - headache, nausea; 4 - the beginning of the toxic effect; 5 - the beginning of a noticeable action; 6 - imperceptible action; T, h - exposure time

It follows from the diagram that even with a low concentration of CO in the air (up to 0.01%), prolonged exposure to it causes a headache and leads to a decrease in performance. A higher concentration of CO (0.02...0.033%) leads to the development of atherosclerosis, the occurrence of myocardial infarction and the development of chronic lung diseases. Moreover, the effect of CO on people suffering from coronary insufficiency is especially harmful. At a CO concentration of about 1%, loss of consciousness occurs after a few breaths. CO also has a negative effect on the human nervous system, causing fainting, as well as changes in the color and light sensitivity of the eyes. Symptoms of CO poisoning are headache, palpitations, shortness of breath and nausea. It should be noted that at relatively low concentrations in the atmosphere (up to 0.002%), CO associated with hemoglobin is gradually released and human blood is cleared of it by 50% every 3-4 hours.

Hydrocarbon compounds

Hydrocarbon compounds have not yet been sufficiently studied in terms of their biological action. However, experimental studies have shown that polycyclic aromatic compounds have caused cancer in animals. Under certain atmospheric conditions (calm, intense solar radiation, significant temperature inversion), hydrocarbons serve as the initial products for the formation of extremely toxic products - photooxidants, which have a strong irritating and general toxic effect on human organs, and form photochemical smog. Carcinogenic substances are especially dangerous from the group of hydrocarbons. The most studied is the polynuclear aromatic hydrocarbon benzo(a)pyrene, also known as 3,4 benzo(a)pyrene, a substance that is a yellow crystal. It has been established that malignant tumors appear in places of direct contact of carcinogenic substances with tissue. If carcinogenic substances deposited on dust-like particles enter the lungs through the respiratory tract, they are retained in the body. Toxic hydrocarbons are also gasoline vapors that enter the atmosphere from the fuel system, and crankcase gases escaping through ventilation devices and leaks in the connections of individual engine components and systems.

Nitric oxide

Nitric oxide is a colorless gas, and nitrogen dioxide is a red-brown gas with a characteristic odor. Nitrogen oxides, when ingested, combine with water. At the same time, they form compounds of nitric and nitrous acids in the respiratory tract, irritating the mucous membranes of the eyes, nose and mouth. Nitrogen oxides are involved in the processes leading to the formation of smog. The danger of their impact lies in the fact that the poisoning of the body does not appear immediately, but gradually, and there are no neutralizing agents.

Soot

Soot, when it enters the human body, causes negative consequences in the respiratory organs. If relatively large soot particles of 2…10 microns in size are easily excreted from the body, then small ones of 0.5…2 microns in size linger in the lungs, respiratory tract, and cause allergies. Like any aerosol, soot pollutes the air, impairs visibility on the roads, but, most importantly, heavy aromatic hydrocarbons, including benzo(a)pyrene, are adsorbed on it.

Sulfur dioxide SO2

Sulfur dioxide SO2 is a colorless gas with a pungent odor. The irritant effect on the upper respiratory tract is due to the absorption of SO2 by the moist surface of the mucous membranes and the formation of acids in them. It disrupts protein metabolism and enzymatic processes, causes eye irritation, cough.

CO2 carbon dioxide

Carbon dioxide CO2 (carbon dioxide) - does not have a toxic effect on the human body. It is well absorbed by plants with the release of oxygen. But if there is a significant amount of carbon dioxide in the earth's atmosphere that absorbs the sun's rays, a greenhouse effect is created, leading to the so-called "thermal pollution". As a result of this phenomenon, the air temperature in the lower layers of the atmosphere rises, warming occurs, and various climatic anomalies are observed. In addition, an increase in the content of CO2 in the atmosphere contributes to the formation of "ozone" holes. With a decrease in the concentration of ozone in the earth's atmosphere, the negative impact of hard ultraviolet radiation on the human body increases.

The car is also a source of air pollution with dust. During driving, especially when braking, as a result of the friction of tires on the road surface, rubber dust is formed, which is constantly present in the air on highways with heavy traffic. But tires are not the only source of dust. Solid particles in the form of dust are emitted with exhaust gases, are brought into the city in the form of dirt on car bodies, are formed from abrasion of the road surface, rise into the air by vortex flows that occur when the car is moving, etc. Dust adversely affects human health, has a detrimental effect on the plant world.

In urban conditions, the car is a source of warming the surrounding air. If 100,000 cars move simultaneously in a city, this is equal to the effect produced by 1 million liters of hot water. Exhaust gases from vehicles containing warm water vapor contribute to climate change in the city. Higher steam temperatures increase heat transfer by the moving medium (thermal convection), resulting in more precipitation over the city. The influence of the city on the amount of precipitation is especially clearly seen in their regular increase, which occurs in parallel with the growth of the city. For a ten-year observation period, in Moscow, for example, 668 mm of precipitation fell per year, in its vicinity - 572 mm, in Chicago - 841 and 500 mm, respectively.

Among the side effects of human activity are acid rain - products of combustion dissolved in atmospheric moisture - oxides of nitrogen and sulfur. This mainly applies to industrial enterprises, the emissions of which are diverted high above the surface level and which contain a lot of sulfur oxides. The harmful effect of acid rain is manifested in the destruction of vegetation and the acceleration of corrosion of metal structures. An important factor here is the fact that acid rains, together with the movement of atmospheric air masses, can overcome distances of hundreds and thousands of kilometers, crossing the borders of states. In the periodical press, there are reports of acid rain falling in different countries of Europe, in the USA, Canada and seen even in such protected areas as the Amazon basin.

Temperature inversions, a special state of the atmosphere, in which the air temperature increases with height, rather than decreases, have an adverse effect on the environment. Surface temperature inversions are the result of intense heat radiation from the soil surface, as a result of which both the surface and the adjacent air layers are cooled. Such a state of the atmosphere prevents the development of vertical air movements, therefore water vapor, dust, gaseous substances accumulate in the lower layers, contributing to the formation of layers of haze and fog, including smog.

The widespread use of salt to combat icing on roads leads to a reduction in the life of cars, causes unexpected changes in roadside flora. So, in England, the appearance along the roads of plants characteristic of sea coasts was noted.

The car is a strong polluter of water bodies, underground water sources. It has been determined that 1 liter of oil can make several thousand liters of water unfit for drinking.

A large contribution to environmental pollution is made by the maintenance and repair of rolling stock, which require energy costs and are associated with high water consumption, the emission of pollutants into the atmosphere, and the generation of waste, including toxic ones.

When performing maintenance of vehicles, divisions, zones of periodic and operational forms of maintenance are involved. Repair work is carried out at production sites. Technological equipment, machine tools, mechanization and boiler plants used in maintenance and repair processes are stationary sources of pollutants.

Table. Sources of release and composition of harmful substances in production processes at operational and repair enterprises of transport

Wastewater

During the operation of vehicles, sewage is generated. The composition and quantity of these waters are different. Waste water is returned back to the environment, mainly to the objects of the hydrosphere (river, canal, lake, reservoir) and land (fields, reservoirs, underground horizons, etc.). Depending on the type of production, wastewater at transport enterprises can be:

• wastewater from car washes
• oily effluents from production sites (washing solutions)
• wastewater containing heavy metals, acids, alkalis
• wastewater containing paint, solvents

Waste water from car washing is from 80 to 85% of the volume of industrial effluents of motor transport organizations. The main pollutants are suspended solids and oil products. Their content depends on the type of car, the nature of the road surface, weather conditions, the nature of the cargo being transported, etc.

Wastewater from washing units, assemblies and parts (waste cleaning solutions) is distinguished by the presence of a significant amount of oil products, suspended solids, alkaline components and surfactants.

Wastewater containing heavy metals (chromium, copper, nickel, zinc), acids and alkalis are most typical for auto repair industries using galvanic processes. They are formed during the preparation of electrolytes, surface preparation (electrochemical degreasing, etching), electroplating and washing of parts.

In the process of painting work (by pneumatic spraying), 40% of paint and varnish materials enter the air of the working area. When carrying out these operations in spray booths equipped with hydraulic filters, 90% of this amount settles on the elements of the hydraulic filters themselves, 10% is carried away with water. Thus, up to 4% of the used paint and varnish materials get into the wastewater of the painting areas.

The main direction in the field of reducing pollution of water bodies, groundwater and groundwater by industrial waste is the creation of systems for recycling water supply to production.

Repair work is also accompanied by soil pollution, accumulation of metal, plastic and rubber waste near production sites and departments.

During the construction and repair of communication lines, as well as production and household facilities of transport enterprises, water, soil, fertile soils, and mineral resources are withdrawn from ecosystems, natural landscapes are destroyed, and flora and fauna are interfered with.

Noise

Along with other modes of transport, industrial equipment, household appliances, a car is a source of artificial noise background of the city, which, as a rule, negatively affects a person. It should be noted that even without noise, if it does not exceed the permissible limits, a person feels discomfort. It is no coincidence that Arctic researchers have repeatedly written about “white silence”, which has a depressing effect on a person, while the “noise design” of nature has a positive effect on the psyche. However, artificial noise, especially loud noise, has a negative effect on the nervous system. The population of modern cities faces a serious problem of noise control, since strong noise not only leads to hearing loss, but also causes mental disorders. The danger of noise exposure is exacerbated by the property of the human body to accumulate acoustic irritation. Under the influence of noise of a certain intensity, changes occur in blood circulation, the work of the heart and endocrine glands, and muscle endurance decreases. Statistics show that the percentage of neuropsychiatric diseases is higher among people working in environments with high noise levels. The reaction to noise is often expressed in increased excitability and irritability, covering the entire sphere of sensitive perceptions. People who are constantly exposed to noise often become difficult to communicate with.

Noise has a harmful effect on the visual and vestibular analyzers, reduces the stability of clear vision and reflex activity. The sensitivity of twilight vision weakens, the sensitivity of daytime vision to orange-red rays decreases. In this sense, noise is an indirect killer of many people on the world's highways. This applies both to drivers of vehicles working in conditions of intense noise and vibration, and to residents of large cities with high noise levels.

Noise in combination with vibration is especially harmful. If a short-term vibration tones the body, then a constant one causes the so-called vibration disease, i.e. a whole range of disorders in the body. The driver's visual acuity is reduced, the field of view narrows, color perception or the ability to judge the distance to an oncoming vehicle may change. These violations, of course, are individual, but for a professional driver they are always undesirable.

Infrasound is also dangerous, i.e. sound with a frequency of less than 17 Hz. This individual and inaudible enemy causes reactions that are contraindicated for a person behind the wheel. The impact of infrasound on the body causes drowsiness, deterioration of visual acuity and a slow reaction to danger.

Of the sources of noise and vibration in a car (gearbox, rear axle, cardan shaft, body, cab, suspension, as well as wheels, tires), the main one is the engine with its intake and exhaust, cooling and power systems.

Rice. Truck noise source analysis:
1 – total noise; 2 - engine; 3 – system of release of the fulfilled gases; 4 - fan; 5 - air inlet; 6 - the rest

However, at vehicle speeds over 50 km/h, tire noise is predominant and increases in proportion to vehicle speed.

Rice. The dependence of the noise of the car on the speed of movement:
1 - range of noise dispersion due to different combinations of road surfaces and tires

The cumulative effect of all sources of acoustic radiation leads to those high noise levels that characterize a modern car. These levels also depend on other reasons:

• pavement condition
• speed and change of direction
• engine speed changes
• loads
• etc.