What delays the current and is safe for humans. Why is electric current dangerous and what effect does it have on the human body? Which current is more dangerous: AC or DC

Chapter 14

FROM THE ACTION OF ELECTRIC CURRENT

ELECTRIC SHOCK HAZARD

The effect of electric current on the human body. Electricity It is currently used in all spheres of human activity: production, everyday life, medicine, etc., as a source of energy, convenient to transport and use. With all the advantages of using electricity, the danger of electricity to humans cannot be ignored.

The effect of electric current on living tissue unlike other factors, it has a peculiar and versatile character. Passing through the body, the electric current produces thermal, electrolytic, mechanical (dynamic) and biological effects.

thermal action manifests itself in the heating of tissues up to burns of individual parts of the body, heating to a high temperature of blood vessels, nerves, heart, brain and other organs that are on the path of the current, which causes serious functional disorders in them.

Electrolytic action causes decomposition of blood and plasma, which is accompanied by significant violations of their physico-chemical composition.

Mechanical (dynamic) action current is expressed in stratification, rupture and other similar damage to various tissues of the body: muscle tissue, walls of blood vessels, vessels of the lung tissue.

Biological action It is expressed in irritation and excitation of the living tissues of the body, which may be accompanied by involuntary convulsive muscle contractions, including the muscles of the heart and lungs, as well as in violation of internal bioelectrical processes that occur in a normally functioning organism and are closely related to its vital functions.

These actions are conditionally reduced to two main types of injuries: local electrical injuries and electric shocks.

Local electrical injuries - these are clearly defined local violations of the integrity of body tissues caused by exposure to electric current or an electric arc. Typical types of local electrical injuries - electrical burns, electrical signs and marks, skin metallization, electrophthalmia and mechanical damage.

Electric shock - This is the excitation of living tissues of the body by an electric current passing through it. It can cause convulsive contraction of muscles without loss of consciousness, with loss of consciousness, without damage or with damage to the work of the heart and respiratory system, as well as clinical death. Clinical or imaginary death - a short-term transitional state from life to death, occurring from the moment the activity of the heart and lungs ceases. The signs of clinical death are as follows: cardiac arrest and, as a result, the absence of a pulse, lack of breathing, the skin is bluish-pale, the pupils of the eyes are sharply dilated (due to oxygen starvation of the cerebral cortex) and do not react to light, pain irritations do not cause any reactions in the victim. The duration of clinical death is determined by the time from the moment of cessation of cardiac activity and respiration until the onset of death of the cells of the cerebral cortex; in most cases it is 4 - 5 minutes.

Factors that determine the outcome of electric shock. In general, the degree of electric shock is determined by the amount of absorbed electrical energy in organs, tissues and systems when an electrical circuit occurs through the human body.

The nature of the impact and the severity of human injury depends on many interrelated factors, such as the strength of the current, the duration of the current, the resistance of the human body, the path of passage, the type (constant, rectified, variable) and frequency of the current, the “attention factor”, the individual properties of the victim and factors environment.

With the increase current strength three qualitatively different responses of the body are clearly manifested: an unpleasant sensation, convulsive contraction of the muscles and fibrillation of the heart. Electric currents that cause an appropriate reaction are divided into tangible, non-release and fibrillation, and their minimum values ​​are usually called threshold.

as show experimental studies, a person begins to feel the flow of an alternating current with a frequency of 50 Hz through him with a power of the order of 0.6 - 1.5 mA. A perceptible current does not cause disturbances in the body's activity, therefore, its long-term flow through the human body under production conditions is permissible.

If a person who has been energized is able to independently overcome the effect of convulsions and free himself from contact with conductors, then such a current is called releasing. In cases where a person cannot free himself from contact, there is a danger of prolonged convulsions. The currents that cause such a reaction of the body are called non-letting currents. The threshold values ​​of non-releasing alternating currents at a frequency of 50 Hz lie within 10 - 15 mA. At 25–50 mA, the action of the current also extends to the muscles of the chest, which leads to difficulty and even cessation of breathing. When exposed to this current for several minutes, death may occur due to the cessation of lung function. There is a dependence of the threshold non-release currents on the weight of a person and his age. So, with an increase in weight from 50 to 80 kg, the value of the threshold current increases by 1.4 - 2 times.

A current of 50–80 mA affects the respiratory and cardiovascular systems. At 100 mA for 2–3 seconds, cardiac fibrillation occurs, which consists in random chaotic contraction and relaxation of the muscle fibers of the heart (fibrils). It stops, circulation stops. This current is called fibrillation.

Duration of current flow Through the human body, it affects the resistance of the skin, as a result of which, with an increase in the time of current exposure to living tissue, its value increases, and the consequences of current exposure to the body increase.

Permissible currents for a person are evaluated according to three electrical safety criteria. First criterion - a perceptible current that does not cause disturbances in the activity of the body and is allowed for a long (no more than 10 minutes per day) flow through the human body in the normal (non-emergency) mode of the electrical installation. For alternating current with a frequency of 50 Hz, its strength is 0.3 mA, and for direct - 1 mA. The releasing current is taken as the second criterion. Its effect on a person is permissible with a flow duration of more than 1 second. The release current for AC is 6 mA, for DC - 15 mA. The third criterion is the fibrillation current, which does not exceed the threshold fibrillation current and is short-term (up to 1 s). The maximum allowable values ​​of alternating currents with a frequency of 50 Hz and contact voltages during emergency operation of industrial electrical installations with voltage up to 1000 V, depending on the duration of exposure, should not exceed the values ​​\u200b\u200bspecified in GOST 12.1.038-82 as amended. dated 01.07.88 and given in Table 14.1.

Table 14.1

Maximum permissible values ​​of contact voltage U etc. and currents I h,

flowing through the human body, in emergency mode

industrial electrical installations with voltage up to 1000 V

Knowledge of the norms for permissible values ​​of contact voltage and currents through the human body is necessary when developing methods and means of protecting people, when assessing electrical safety conditions in existing electrical installations, and when investigating electrical injuries.

Electrical resistance of the human body is a variable that depends on the touch voltage, the condition of the skin, the parameters of the electrical circuit, physiological factors and the state of the environment.

Complete electrical resistance The human body has active and capacitive components and consists of the resistance of the skin and the resistance of internal tissues.

The upper layer of the skin, called the epidermis, and consisting mainly of dead keratinized cells, has a high resistance, which determines the overall resistance of the human body. The resistance of the lower layers (dermis) and internal human tissues is insignificant (300–500 ohms). With dry, clean and intact skin, the resistance of the human body, measured at voltages up to 15–20 V, ranges from (3–100) × 10 3 Ohm. When moistened, as well as when it is damaged (under the contacts), the resistance of the body turns out to be the smallest - about 500 Ohm, i.e. reaches a value equal to the resistance of the internal tissues of the body. For approximate calculations, the resistance of the human body is considered purely active and equal to 1 kOhm at touch voltages above 50 V, 6 kOhm at touch voltages less than 50 V.

The inclusion of vital organs of a person in the zone of action of the current increases the possibility of a severe outcome. The most dangerous are the loops when the head and spinal cord. A fatal outcome is possible even at low voltages (12 V), if the current passes through the biologically active points of the body on the neck, temples, lower leg, shoulders, back and other places of the human body.

At voltages up to 500 V, alternating current is more dangerous; with a further increase in voltage, the danger direct current is growing rapidly.

When the frequency of the alternating current changes from zero to 100 Hz, the danger of injury at the same voltage increases, reaching a maximum in the range of 50 - 60 Hz, at a frequency of 200 Hz, the risk of fibrillation is reduced by 2 times, at a frequency of 400 Hz - more than 3 times.

Currents above 500,000 Hz do not cause electric shock, but they can cause thermal burns.

A certain influence on the outcome of the lesion has a physical and psychological condition person. Fatigue, depressed mental state, alcohol consumption, a number of diseases increase the risk of exposure to electric current. Therefore, a list of diseases has been defined, in the presence of which work in existing electrical installations is not allowed. Maintenance of electrical installations is entrusted to employees who have passed medical checkup And special education. Great importance has an "attention factor" that reduces the danger of current.

In general, people in the room are less at risk. However, if this is a production room, then the presence of dampness, conductive dust, many types of electrical equipment, and aggressive environments increase the risk of electric shock.

Classification of premises according to the danger of electric shock. In accordance with the Electrical Installation Rules (PUE), all premises are divided into three classes in relation to the danger of electric shock to people: without increased danger, with increased danger, especially dangerous.

Premises without increased danger - these are dry, dust-free rooms with normal air temperature and with insulating (for example, wooden) floors, i.e. in which there are no conditions that create an increased or special danger. Such premises include office premises, tool rooms, laboratories, etc.

High risk areas characterized by the presence in them of one of the following conditions that create an increased danger: dampness (relative humidity exceeds 75% for a long time) or conductive dust (coal, metal, etc.); conductive floors (metal, earthen, reinforced concrete, brick, etc.); high temperature (air temperature above +35 C); the possibility of a person simultaneously touching the metal structures of buildings connected to the ground, technological devices, mechanisms, etc., on the one hand, and to the metal cases of electrical equipment - with another.

Examples of premises with increased danger are stairwells of buildings with conductive floors, storage rooms that are not heated, etc.

Particularly dangerous premises, characterized by the presence of one of the following conditions that create a particular danger: extreme dampness (relative humidity close to 100%); chemically active or organic environment that destroys insulation and current-carrying parts of electrical equipment; two or more high-risk conditions at the same time.

Particularly dangerous premises are most of the industrial premises, including all equipment repair shops, workshops, etc.

Territories of location of outdoor electrical installations (in the open air or under a canopy) in relation to the danger of electric shock to people are equated to especially dangerous premises

Electrical safety is understood as a system of organizational and technical measures to protect a person from the action of damaging factors of electric current.

Electrical injury is the result of exposure to an electric current and an electric arc.

An electric current passing through a living organism produces:

thermal (thermal) effect, which is expressed in burns of individual parts of the body, heating of blood vessels, blood, nerve fibers, etc.;

electrolytic (biochemical) action - expressed in the decomposition of blood and other organic fluids, causing significant violations of their physico-chemical compositions;

biological (mechanical) action - expressed in irritation and excitation of living tissues of the body, accompanied by involuntary convulsive contraction of muscles (including the heart, lungs).

Electrical injuries include:

electrical burns (current, contact arc, as well as combined);

electric signs (“tags”), leather metallization;

· mechanical damage;

· electrophthalmia;

electric shock (electric shock).

Depending on the consequences, electric shocks are divided into four degrees:

convulsive muscle contraction without loss of consciousness;

convulsive muscle contraction with loss of consciousness;

loss of consciousness with impaired breathing or cardiac activity;

A state of clinical death as a result of cardiac fibrillation or asphyxia (suffocation).

The main adverse effects that may occur due to electric shock:

The flow of electric current through human organs can cause cardiac arrest, breathing; muscle ruptures, brain damage, burns. Such damage is typical for a damaging current of more than 10 milliamps, however, even a sensing current (1-2 mA) can frighten a person, as a result of which mechanical injuries are not excluded (for example, due to a fall from a height).

Factors that determine the outcome of the lesion.

The main factors that determine the outcome of the lesion are:

the magnitude of the current and voltage;

duration of current exposure;

Body resistance

Loop ("path") of the current;

· psychological readiness for impact.

The magnitude of the current and voltage.

Electric current, as a damaging factor, determines the degree of physiological impact on a person. Voltage should be considered only as a factor that determines the flow of a particular current under specific conditions - the greater the touch voltage, the greater the damaging current.

According to the degree of physiological impact, the following damaging currents can be distinguished:

threshold perceptible current - the smallest value of the current that causes perceptible irritation;

threshold non-release current - the value of the current that causes convulsive muscle contractions that do not allow the affected person to free themselves from the source of the lesion;

threshold fibrillation current - the value of the current that causes fibrillation of the heart.

Fibrillation is called chaotic and multi-temporal contractions of the fibers of the heart muscle, completely disrupting its work.

Average values ​​of threshold currents Current Current value

threshold perceptible, mA threshold non-releasing, mA threshold fibrillation, mA

Variable frequency 50 Hz 0.5... 1.5 6... 10 50...100

Permanent 5.0...20 50...80 300

The outcome of the lesion is strongly influenced by the resistance of the human body. The highest resistance (3 ... 20 kOhm) has the upper layer of the skin (0.2 mm), consisting of dead keratinized cells, while the resistance of the cerebrospinal fluid is 0.5 ... 0.6 Ohm. The total resistance of the body due to the resistance of the upper layer of the skin is quite large, but as soon as this layer is damaged, its value decreases sharply.

In calculations related to electrical safety, the resistance of the human body is taken equal to 1 kOhm.

The duration of the action of the current significantly affects the outcome of the lesion, since over time the resistance of the human skin drops sharply, heart damage becomes more likely and other negative consequences occur.

The most dangerous is the passage of current through the heart, lungs and brain.

The degree of damage also depends on the type and frequency of the current. The most dangerous is alternating current with a frequency of 20 ... 1000 Hz. Alternating current is more dangerous than direct current at voltages up to 300 V. At high voltages - direct current.

Electric shock to a person can occur in the following cases:

touching a person who is not isolated from the earth to the live parts of electrical installations that are under voltage;

approaching a person who is not insulated from the ground, at a dangerous distance to current-carrying parts of electrical installations that are not protected by insulation. The latter are under tension;

touching a person not isolated from the ground to non-current-carrying metal parts (cases) of electrical installations that are energized due to a short circuit to the case;

contact of a person with two points of the earth (floor) under different potentials in the current spreading field ("step voltage");

lightning strike;

the action of an electric arc;

releasing another person under tension.

The path ("loop") of current through the human body.

When investigating accidents associated with the impact of electric current, first of all it turns out which way the current flowed. A person can touch current-carrying parts (or non-current-carrying metal parts that may be energized) with a variety of parts of the body. Hence the variety of possible current paths.

The most likely are the following:

"right arm - legs" (20% of lesions);

« left hand- legs" (17%);

"both arms - legs" (12%);

"head - legs" (5%);

"hand - hand" (40%);

"leg - leg" (6%).

All loops, except the last one, are called "large" or "full" loops, the current captures the region of the heart and they are the most dangerous. In these cases, 8-12 percent of the total current flows through the heart. The "leg - leg" loop is called "small", only 0.4% of the total current flows through the heart. This loop occurs when a person finds himself in the current spreading zone, falling under the step voltage.

Not every current kills
But any current can kill.
Austrian scientist S. Jellinek

Every year, up to 30 thousand people die from electric shock.

Students take turns giving examples of accidents with teenagers.

Leading: Dry statistics of numbers, and behind it someone's tears, the collapse of hopes and lives.

We cannot imagine our life without a refrigerator, TV, computer. Electricity has firmly entered our lives, has become commonplace. And over time we become careless, forgetting about the danger that electric current poses. You guys have started practice in the welding workshop, and not far off summer holidays and lots of free time. Therefore, our today's briefing lesson will affect both industrial and domestic electrical safety, and it is called "This useful and dangerous electric current" (the name appears on the screen). Guys, you should have prepared electrical safety questions in advance, the answers to which you would like to know. Have you prepared? Well done! Who wants to start first?

1. Is household electricity dangerous?

The strength of the current that flows in the wires of our apartments is 5-10A, which is deadly. Already at J = 0.1-0.15A, a person cannot independently break away from the electrical wire. An example of a dangerous situation in everyday life is given.

2. What are the consequences of the action of electric current on the body? (in the process of answering, pictures appear on the screen - explanations follow).

The current passes through the human body, affects the central nervous system, thereby disrupting breathing and cardiac activity. Electric shock can result in electrical burns, mechanical injury due to muscle contraction, and electric arc blindness. The most vulnerable parts of the human body are described below.

3. What factors affect the extent of electrical damage? .

The amount of current passing through the human body depends on the resistance of the human body. The lower the resistance of the body, the higher the current. The resistance decreases from: high voltage, skin condition, exposure time, O2 content in the air, high air t. The danger of electric shock depends on the path of current in the human body. The most dangerous is the current loop, the path of which lies through the heart. The leading cause of death from electric shock is fibrillation (rhythm disturbance) hearts.

4. What should I do if someone gets electrocuted?

Immediately, not forgetting about your own safety, provide assistance, first of all, freeing the victim from the effects of electricity. Having quickly de-energized the victim, you can turn off the power source; throwing off the wires from the victim with any non-conductive object; cutting or interrupting the wires on different levels; dragging the victim by the clothes. Only then can you start helping.

5. Why is it dangerous to be near a broken wire lying on the ground?

The earth, being a conductor of electric current, becomes, as it were, a continuation of the wire. The path of the current is not interrupted, and it spreads over the ground. An electric shock occurs when the feet touch two points of the ground, the wider the step, the more likely the shock. A dangerous zone is formed around a broken wire lying on the ground within a radius of 8-10 m. When entering the step voltage zone, a person is in danger, even if he does not touch the wire. You can leave the danger zone in steps without taking your feet off the ground and without creating a gap between your feet.

Leading: You have many questions, all of which you will receive answers over time. And now I want to ask you - where does the danger of electric shock lie in wait for you?

The children take turns listing the objects of danger.

Well done! In order to avoid an accident, each of you should know that the places of possible electric shock are marked with special warning signs. It is unacceptable to neglect them, and even more so to remove them.

Leading: Your profession is electrically dangerous, but do you know the main causes of electrical injuries?

Answer.

Leading: Guys, listen carefully to the production situation and determine the reasons for the accident with the worker.

Example: A team of locksmiths was installing blower pipelines. During operation, the welding transformer windings closed and the voltage from the high side entered the welding circuit. At this time, the electric welder touched the welding wire at the place where the insulation was broken, and received a fatal injury.

Lack of grounding of the secondary winding and the use of a cable with broken insulation led to an accident.

Work was carried out to connect the fire water supply to the previously installed valve. The electric welder put welding wires that were twisted into the fire well. The places of the twists were "insulated" by the material from the mittens. In the process of work, the electric welder stepped on a welding twist of wires lying on a fire-fighting water pipe, while the welding wire closed on the pipe (due to a violation of the insulation of the twist). The overalls of the electric welder caught fire, which was facilitated by its severe pollution, and he received severe burns, despite timely assistance.

The guys determine its cause.

Leading: And now attention! Situational task, carefully read and choose the correct answers and arrange them in order of priority.

Correct answers: 5, 7, 2, 1 or 5, 9, 2, 1

To finally consolidate the acquired knowledge, we offer test tasks.

TESTS

I. What is the best way to drop an electric wire from an unconscious person in your apartment:

1. Dry-handled mop brought from the bathroom.
2. With a dry house slipper taken from your foot.
3. With a dry wooden stick brought from the yard.
4. A thick magazine or book lying nearby on the table.

II. The sequence of actions when providing the first medical care to an electric shock victim lying unconscious in a bath:

1. Drain the water from the bath.
2. Enter the bathroom and turn off all electrical appliances from the network.
3. Turn off the electricity in the entire apartment.
4. Assess the condition and start cardiopulmonary resuscitation.
5. Call the ambulance team.

III. The sequence of actions when providing first aid to an injured person lying unconscious under an electric wire of city lighting on a lawn near a walking path:

1. Discard the wire with any non-conductive object.
2. Assess the condition of the victim and, in the absence of a pulse on the carotid artery, strike the chest.
3. Pull the victim 3-4 meters away from the wire lying on the ground and place him on a footpath free of grass.
4. Pull the victim 3-4 meters away from the wire lying on the ground away from the footpath that people can walk on.
5. Quickly run up to the victim or approach with large steps.
6. Carefully approach with a goose step.
7. Ask others to call an ambulance.

Correct answers: I (2, 4); II (3, 2, 1, 4, 5); III (6, 1, 4, 2, 7)

But before we part with you - 5 commandments - how to avoid electric shock.

This concludes our briefing lesson, I hope each of those present received useful information, be healthy!

1. O.N. Kulikov “Labor protection in the production of welding works”, M .: “Academy”, 2005.
2. Journal "Library of an engineer for labor protection", No. 11, 2006.
3. Materials of the "Republican seminar on the prevention of children's electrical injuries", 2006.

The current at which a person can independently free himself from the electrical circuit should be considered acceptable. Its value depends on the rate of passage of current through the human body: with a duration of more than 10 s - 2 mA, and for 120 s or less - 6 mA.

The safe voltage is considered to be 36 V (for lamps of local stationary lighting, portable lamps, etc.) and 12 V (for portable lamps when working inside metal tanks, boilers). But under certain situations, even such voltages can be dangerous.

Safe voltage levels are obtained from the lighting network using step-down transformers. It is impossible to extend the use of safe voltage to all electrical devices.

Two types of current are used in production processes - direct and alternating. They have different effects on the body at voltages up to 500 V. The danger of injury from direct current is less than alternating current. The greatest danger is the current with a frequency of 50 Hz, which is standard for domestic electrical networks.

The path along which the electric current passes through the human body largely determines the degree of damage to the body. The following options for the directions of current flow through the human body are possible:

• - a person touches current-carrying wires (parts of equipment) with both hands, in this case there is a direction of current flow from one hand to the other, i.e. “hand-hand”, this loop is most common;
• - when touching with one hand to the source, the current path closes through both legs to the ground “arm-legs”;
• - in the event of a breakdown of the insulation of the current-carrying parts of the equipment, the hands of the worker are energized on the case, at the same time, the flow of current from the equipment case to the ground leads to the fact that the legs are energized, but with a different potential, this is how the “hands-feet” current path arises ;
• - when current drains to earth from faulty equipment, the earth nearby receives a changing voltage potential, and a person who stepped on such earth with both feet finds himself under a potential difference, i.e. each of these feet receives a different voltage potential, as a result, a step voltage arises and the leg-to-leg electrical circuit, which happens the least and is considered the least dangerous;
• - touching the head to the current-carrying parts can cause, depending on the nature of the work performed, the current path to the arms or legs - “head-arms”, “head-legs”.

All options differ in the degree of danger. The most dangerous are the options “head-arms”, “head-legs”, “arms-legs” (full loop). This is due to the fact that vital important systems body - brain, heart.

The duration of current exposure affects the final outcome of the lesion. The longer the electric current acts on the body, the more severe the consequences.

environmental conditions, human environment in the course of work activities may increase the risk of electric shock. Increase the risk of electric shock high temperature and humidity, metal or other conductive floor.

According to the degree of danger of electric shock to a person, all premises are divided into three classes: without increased danger, with increased danger, especially dangerous.

The nature of the impact of alternating and direct current on the human body is presented in table 1.

Table 1 - The nature of the impact of alternating and direct current on the human body

In everyday life and at work, we are faced with various electrical appliances, electrical installations. By following the rules of electrical safety and having knowledge in this area, you can reduce the likelihood of falling under the dangerous effects of electric current and voltage.

IN this issue engineering and medical knowledge is combined, the use of which in combination will increase the result in reducing the level of electrical injuries at home and at work.

The effect of electric current on the human body

Current, unlike other hazardous media, has no color, no smell, and is invisible.

Electric current has the following types of effects on the human body: thermal, electrolytic, biological. Let's consider each of these influences in more detail.

The thermal effect consists in burns of parts of the body, heating of blood vessels and nerve endings. This type of action is also called thermal. Because the thermal energy obtained from the electrical forms burns.

Electrolytic action results in the decomposition of blood and other fluids in the body through the process of electrolysis, which causes disturbances in the physico-chemical composition of these fluids. The essence of damage is molecular level- thickening of the blood, a change in the charge of proteins, vapor and gas formation in the body.

Biological impact electric current on the body is accompanied by irritation and excitation of the organs. It causes convulsions, contractions.

In the case of the heart and lungs, this effect can be fatal due to the cessation of the activity of the respiratory and heart organs.

Biological impact causes mechanical damage to human organs and joints. Also, mechanical damage can be caused by a person falling from a height due to the effects of electric current.

Dangerous, safe and deadly current for humans

No amount of current can be considered safe for humans. There is only a more or less dangerous amount of electric current. Each person has internal resistance, the value of which is influenced by many factors (skin thickness, humidity of the room and human body, current flow path).

The most dangerous path of current flow is the direction of the foot-head, hand-head, since in this case the way goes through the heart, brain, respiratory organs. A large amount of current can cause cardiac arrest and respiratory arrest. These reasons are the most probable causes lethal outcomes due to the flow of electric current.

It is believed that direct current is safer than alternating current in networks up to 500. At voltages above 500 volts, the danger of direct current increases.

The frequency of the network affects the severity of electrical injury. The industrial frequency of 50 Hz is more dangerous than the frequency of 500 Hz. At a high frequency, the so-called "skin effect" is observed, when the current does not pass through the entire conductor, but only along its surface. This means that the internal organs are not directly affected.

Also, the degree of danger of current exposure to a person is affected by the duration of a person's stay under the influence of current. Here the dependence is linear - the longer, the more destruction and adverse effects.

Here are the threshold values ​​of alternating and direct current and the possible reactions of the body to these effects:

When passing through the human body, current can create electrical injury or electrical shock.

Electric shock means that the current excites the tissues of the body, which causes them to contract and convulsions. There are 4 groups of electric shocks: convulsions, convulsions with loss of consciousness, loss of consciousness with impaired breathing and heart function, clinical death.

In case of electrical injury, the current causes direct damage to human tissues and organs. These can be electrical burns, metallization of the skin, electrical marks and mechanical damage.

Electric burns are current and arc. The action of a current burn is associated with the passage of current through the human body. An arc burn occurs between a person and a high voltage conductor, due to the occurrence between them. The temperature of the arc can reach thousands of degrees Celsius. Such a burn is much more dangerous and can, in addition, be accompanied by a fire in the victim’s clothes.

Metallization of the skin occurs when, under the influence of current, metal particles enter the skin, while the conductivity of the skin increases, which increases the risk of injury.

Electrical tags are places through which current enters and exits the human body. Most often found on the legs and arms.

In any case, you should try to avoid touching current-carrying parts with conductive objects (fishing under power lines, carry a ladder near voltage buses), do not use wires and cables with weakened insulation, observe safety rules when staying and working in electrical installations. Take care of the health of yourself and your family.

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