• Elovsky branch of GBOU SPO
• "Osa Vocational Pedagogical College"

• Lesson in the discipline "Occupational Safety" in the profession "Auto mechanic"

• Electrical injury is a painful condition of the body caused by exposure to electric current. The severity of electrical injury depends on the parameters of the current and the duration of its impact. The main danger in case of electrical injury is not a burn, but physiological disorders associated with the passage of current through vital organs.

• Electricity surrounds us everywhere, it’s hard to imagine existence without it. modern man. But are you ready to really provide help if someone next to you, as people say, “gets an electric shock”?

• First aid in case of electric shock must be provided immediately, directly at the scene of the incident.

• Firstly, you should immediately stop exposing a person to electric current: unplug the plug from the socket, turn off the switch, circuit breaker, safety plugs, throw away the exposed wire, etc. At the moment the current is turned off, you should provide fall insurance for the victim if the damage occurs electric shock happened at altitude.

• Until the tension is relieved, you, too, may be injured when touching the victim. Use insulating material: dry rubber gloves to pull the victim aside, or a wooden stick to push away the exposed wire.
• After this, you should call an ambulance and assess the condition of the victim yourself. If there are no severe injuries with loss of consciousness, a sedative and analgesic should be given (5-10 drops of valerian or Corvalol tincture, 0.1 g of analgin), warm tea.

• In case of severe injuries with loss of consciousness, it is necessary to constantly monitor the victim’s breathing and heartbeat. In case of cardiac arrest, you must immediately begin mouth-to-mouth artificial respiration and chest compressions. Sometimes cardiac activity can be restored with a sharp blow to the sternum with the palm of the hand.

• After making sure that cardiac activity and breathing have been restored, you need to apply dry aseptic dressings to the electrical burn areas. In case of possible fractures, apply splints to the fracture sites using improvised means.
• If, after being released from the current, the victim has no signs of life, artificial respiration and closed heart massage must be immediately started and continued without interruption until the ambulance arrives. At the same time, warm the victim with a blanket, clothing, and heating pads.

• In the event that before arrival medical workers you have managed to restore breathing and cardiac activity, apply a dry sterile bandage to the affected area. For a minor burn, use a regular bandage; for a widespread burn, use clean sheets or cloth. Should not be applied to a burn site medicines- no liquids, no ointments, no powders!
• All those injured by electric shock must be taken to medical institution, and always on a stretcher, regardless of how you feel. This must be done because cardiac and respiratory disorders may occur again.

• Chumachenko Yu.T., Chumachenko G.V., Efimova A.V. Operation of automobiles and labor protection in motor transport. – Rostov-on-Don: Phoenix, 2002.
• http://www.orshanka.by/?p=13134 – fig. 2 slide
• http://www.culture.mchs.gov.ru/wap/medical/algorithms_of_first_aid_to_victims_of_traumatic_injuries_and_urgent_situations/first_aid_for_electric_shock/ fig. Slide 3, 4, 5

1. Freeing the victim from the action of electric current In case of electric shock, it is necessary to free the victim from the action of electric current as quickly as possible, because The severity of the electrical injury depends on the duration of this action. Voltage up to 1000 V To free the victim from the action of electric current, if he cannot do this on his own, it is necessary to separate him from the live parts that he touches: - turn off the installation or equipment using switching equipment (switch, circuit breaker, circuit breaker) or by removing fuses, plug connector; - pull the victim by dry clothes;

2. Assessing the physical condition of the victim After releasing the victim from the action of electric current, it is necessary to assess his physical condition. In case of electric shock, death is often clinical (imaginary). The victim cannot be considered dead due to lack of breathing, heartbeat, or pulse. Only a doctor can give an opinion on the continuation or futility of the action to revive the victim. With certain skills, the person providing assistance is able to assess the condition of the victim within one minute and decide in what order to provide assistance to him. Loss of consciousness is judged visually and, to ensure its absence, you can contact the victim with a question about his well-being. The color of the terminal integument and the presence of respiration are assessed visually.

You should not waste time applying a mirror or shiny metal objects to the victim’s mouth and nose to determine the presence of breathing. The pulse on the carotid artery is felt with the pads of the second, third and fourth fingers, positioned along the neck between the Adam’s apple and the sternocleidomastoid muscle and lightly pressing them in the direction of the spine. Width of the pupils. with eyes closed, it is determined as follows: - place the fingertips on the upper eyelids and, lightly pressing them towards eyeball, lift up. A dilated pupil indicates a sharp deterioration in blood supply to the brain.

3. Rendering first aid The victim is revived by restoring breathing and heart function. Once you start reviving, you need to call a doctor or an ambulance. This should be done not by the person providing assistance, but by someone else. Before performing artificial respiration, it is necessary to: Lay the victim on his back; Unbutton clothing that restricts breathing; Ensure patency of the upper respiratory tract by freeing the larynx from the sunken tongue; Empty the cavity from foreign contents.

To free the upper respiratory tract, the person providing assistance is located on the side of the victim’s head, places one hand under his neck, and with the palm of the other hand presses on his forehead, throwing his head back as much as possible. In this case, the root of the tongue rises and the entrance to the larynx is freed, the victim’s mouth opens, the upper respiratory tract become open. Foreign contents in the oral cavity are removed with a finger wrapped in a scarf, cloth or bandage.

Carrying out artificial respiration Most in effective ways artificial respiration are “mouth to mouth” and “mouth to nose”, referring to the method of insufflation, when the air inhaled during the provision of assistance is forcibly supplied into the respiratory tract of the victim. The person providing assistance takes a deep breath with an open mouth, leans towards the victim’s face, completely tightly grabs the victim’s open mouth with his lips and with some effort takes an energetic breath.

As soon as the victim’s chest rises, the air injection is stopped, the person providing assistance removes his mouth from the victim’s mouth, and the victim exhales passively. Air can be blown through gauze, a scarf, or an “air duct.” The interval between artificial breaths should be seconds (12 respiratory cycles).

If after blowing air the chest does not expand, it is necessary to move the victim’s lower jaw forward. To do this, with four fingers of both hands, grab the lower jaw from behind by the corners and, resting your thumbs on its edge (below the corners of the mouth), pull it with your fingers to its edge, pull it back and push the jaw forward so that the lower teeth stand in front of the upper teeth. If the victim’s jaws are clenched tightly and it is not possible to open his mouth, artificial respiration should be performed “mouth to nose.”

A good indicator of the effectiveness of artificial respiration, except for expansion chest, may cause pinking of the mucous membranes of the skin, as well as the victim’s emergence from an unconscious state and the appearance of independent breathing. When performing artificial respiration, the person providing assistance must ensure that air does not enter the victim’s stomach. If air gets into the stomach, as evidenced by bloating in the stomach, gently press the palm of your hand on the stomach between the sternum and the navel. This may cause vomiting, in which case it is necessary to turn the victim's head and shoulders to the side to clear his mouth and throat.

External cardiac massage In case of electric shock, not only breathing can stop, but also blood circulation can stop when the heart does not circulate blood through the vessels. In this case, it is necessary to restore blood circulation artificially. When artificial respiration is combined with external cardiac massage, the functions of breathing and circulation are simulated. If you press on the sternum, the heart will be compressed between the sternum and the spine and blood will be squeezed out of its cavities into blood vessels. If you press on the sternum with jerking movements, then blood will be pushed out of the cavities of the heart almost the same way as it happens during natural contraction. This is called external cardiac massage, in which blood circulation is artificially restored.

If the victim's heart stops, he must be immediately placed on level base: bench, floor and place a board under your back. No rollers should be placed under the neck and shoulders. If one person is providing assistance, he is located on the side of the victim and makes 2 quick blows “from mouth to mouth” or “from mouth to nose”. Remaining on the same side of the person lying down, he rises, places the palm of one hand on the lower half of the sternum, and raises his fingers. Place the palm of the second hand on top of the first and press, helping by tilting your body. When applying pressure, the hands should be straightened at the joints. Pressure should be applied in quick bursts so as to displace the sternum by 4-5 cm, the duration of pressure is no more than 0.5 seconds. The interval between pressures is 0.5 seconds. During pauses, the hands are not removed from the sternum, the fingers remain straight, the arms are fully straightened at the elbow joints.

For every 2 injections, 15 pressures are applied to the sternum, i.e. in one minute you need to do 72 manipulations. Revival can be carried out by 2 people: one does artificial respiration, the other does cardiac massage. During artificial inhalation of the victim, the one who massages the heart does not apply pressure, because the forces developed when pressing are much greater than when blowing.

If resuscitation is carried out correctly, skin turn pink, the pupils narrow, independent breathing is restored. After cardiac activity is restored and the pulse is well determined, cardiac massage is immediately stopped, artificial respiration is continued if the victim’s breathing is weak. At the same time, so that natural and artificial breaths coincide. If artificial respiration and closed cardiac massage are ineffective, resuscitation is stopped after 30 minutes.

1 slide

Electrical Hazard Analysis Diagrams electrical networks ZNT INT ZNT - network with a grounded neutral point of the transformer; INT - network with an isolated neutral point (NT); (0 - 0) - neutral protective conductor; R0 - working grounding of NT; Ri is the phase insulation resistance relative to ground; C - capacity; Ul - linear voltage (380V); Uph - phase voltage (220V).

2 slide

Dangerous situations electric shock 1. Accidental two-phase or single-phase contact with live parts. 2. Approaching a person at a dangerous distance to high-voltage buses (according to regulations, the minimum distance is 0.7 m.) 3. Touching metal non-current-carrying parts of equipment that may become live due to insulation damage or erroneous actions of personnel. 4. Getting under step voltage when a person moves through the zone of current spreading from a wire that has fallen to the ground or short circuit of live parts to the ground.

3 slide

Two-phase touching of live parts The most dangerous case is touching two phase wires(a) and to the phase and neutral wires (b). Current Ich passing through a person and touch voltage Upr (V) with human resistance Rch (Ohm): Touch voltage is the potential difference between two points in the circuit that a person touches with the surface of the skin. Current path - “hand-to-hand”

4 slide

Single-phase touch to the network with ZNT This case is less dangerous than two-phase touch, since the resistance of the shoes Rob and the floor Rp is included in the damage circuit. R = Rch+ Rob+ Rp Damage chain: Networks with ZNT are used in enterprises, cities, and rural areas. Current path - “arm-leg”

5 slide

Single-phase contact with a network with an INT This case is less dangerous than for a network with a ZNT with normal insulation resistance Ri (Ohm), but the danger for a long-distance network may increase due to the presence of capacitive current. With the same R and each phase, the total insulation resistance is equal to: Networks with INT are used for short lines. They require constant monitoring of R and. Current path - “arm-leg”

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Slide 6

Slide 7

The presentation on the topic “Analysis of Electric Shock Hazards” can be downloaded absolutely free of charge on our website. Project subject: Physics. Colorful slides and illustrations will help you engage your classmates or audience. To view the content, use the player, or if you want to download the report, click on the corresponding text under the player. The presentation contains 7 slide(s).

Presentation slides

Slide 1

Electrical Hazard Analysis

Electrical network diagrams

ZNT - network with a grounded neutral point of the transformer; INT - network with an isolated neutral point (NT); (0 - 0) - neutral protective conductor; R0 - working grounding of NT; Ri is the phase insulation resistance relative to ground; C - capacity; Ul - linear voltage (380V); Uph - phase voltage (220V).

Slide 2

Hazardous Electrical Situations

1. Accidental two-phase or single-phase contact with live parts.

2. Approaching a person at a dangerous distance to high-voltage buses (according to standards, the minimum distance is 0.7 m.)

3. Touching metal non-current-carrying parts of the equipment that may become live due to damaged insulation or erroneous actions of personnel.

4. Getting under step voltage when a person moves through the zone of current spreading from a wire that has fallen to the ground or short circuit of live parts to the ground.

Slide 3

Two-phase touching of live parts

The most dangerous case is touching two phase wires (a) and the phase and neutral wires (b).

Current Ich passing through a person and touch voltage Upr (V) with human resistance Rch (Ohm):

Touch voltage is the potential difference between two points in the circuit that a person touches with the surface of the skin.

Current path - “hand-to-hand”

Slide 4

Single-phase touch to the network with ZNT

This case is less dangerous than a two-phase touch, since the resistance of the shoes Rob and the floor Rp are included in the damage circuit.

R = Rch+ Rob+ Rp Damage chain:

Networks with ZNT are used in enterprises, cities, and rural areas.

Current path - “arm-leg”

Slide 5

Single-phase network touch with INT

This case is less dangerous than for a network with ZNT with normal insulation resistance R (Ohm), but the danger for a long-distance network may increase due to the presence of capacitive current.

With the same R and each phase, the total insulation resistance is equal to:

Networks with INT are used for short lines. They require constant monitoring of R and.

Slide 6

Electrical injury is a painful condition of the body caused by exposure to electric current. The severity of electrical injury depends on the parameters of the current and the duration of its impact. The main danger in case of electrical injury is not a burn, but physiological disorders associated with the passage of current through vital organs. Electricity surrounds us everywhere; without it it is difficult to imagine the existence of modern man. But are you ready to really provide help if someone next to you, as people say, “gets an electric shock”?

First aid in case of electric shock must be provided immediately, directly at the scene of the incident. Firstly, you should immediately stop exposing a person to electric current: unplug the plug from the socket, turn off the switch, circuit breaker, safety plugs, discard the exposed wire, etc. At the moment the current is turned off, insurance should be provided for the victim against falling if an electric shock occurs on top.

Until the tension is relieved, you, too, may be injured when touching the victim. Use insulating material: dry rubber gloves to pull the victim aside, or a wooden stick to push away the exposed wire. After this, you should call an ambulance and assess the condition of the victim yourself. If there are no severe injuries with loss of consciousness, a sedative and analgesic should be given (510 drops of valerian or Corvalol tincture, 0.1 g of analgin), warm tea.

In case of severe injuries with loss of consciousness, it is necessary to constantly monitor the victim’s breathing and heartbeat. In case of cardiac arrest, you must immediately begin mouth-to-mouth artificial respiration and chest compressions. Sometimes cardiac activity can be restored with a sharp blow to the sternum with the palm of the hand.

After making sure that cardiac activity and breathing have been restored, you need to apply dry aseptic dressings to the electrical burn areas. In case of possible fractures, apply splints to the fracture sites using improvised means. If, after being released from the current, the victim has no signs of life, artificial respiration and closed heart massage must be immediately started and continued without interruption until the ambulance arrives. At the same time, warm the victim with a blanket, clothing, and heating pads.

If you managed to restore your breathing and cardiac activity before the arrival of medical workers, apply a dry sterile bandage to the affected area. For minor burns, use a regular bandage; for larger burns, use clean sheets or cloth. Do not apply any medications, liquids, ointments, or powders to the burn site! All those injured by electric current must be taken to a medical facility, and always on a stretcher, regardless of their state of health. This must be done because cardiac and respiratory disorders may occur again.

Sources: 1. Chumachenko Yu.T., Chumachenko G.V., Efimova A.V. Operation of automobiles and labor protection in motor transport. – Rostov on Don: Phoenix, – fig. 2 slide 3. st_aid_to_victims_of_traumatic_injuries_and_urgent_situation s/first_aid_for_electric_shock/ fig. Slide 3, 4, 5http:// st_aid_to_victims_of_traumatic_injuries_and_urgent_situation s/first_aid_for_electric_shock/