Use and Maintenance

The great industrial and domestic diffusion of the electrical current, together with the fact that he is not perceivable by the senses, makes fall to the people in a routine, unconcern and lack of prevention in the use of the electrical equipment. 

On the other hand given to its nature and the effects, often mortal, that its passage by the human body causes, they cause that the electrical current is a source of accidents of such magnitude that are not due to haggle over efforts to obtain the maximum forecasts against the electrical risks.



The kids are the first causes of the electrical accidents in the house.

 

Indicative data of accidents of electrical origin:

- 0,30% of the working accidets with low.

- 1% of the accidents cause a permantent incapacity.

 

In companies dedicated to the production and transport of electrical energy.

- 3% of the accidents that they inflict losses.

- 50% of the accidents are fatal.



Electrical picture located in a dangerous place due to high humidity level

 

DETERMINANT ELEMENTS OF THE ELECTRICAL ACCIDENTES:

1º - Negligence.

2º - Dangerous electrical systems of permanent taking.

3º - Electrical systems with temporary defects.

4º - Due to another person.

5º - Forgetfulness of norms or danger

6º - Ignorance.

7º - Lack of monitoring.

8º - Error.

9º - Other cases.

The 15% of the electrical accidents are fatal.

 

 

FACTORS THAT INFLUENCE IN THE ELECTRICAL EFFECT

The human body to the being crossed by the electrical current, the law of Ohm behaves like a conductor following.

Where:  The Intensity is equal to the Difference of potential / Resistance

  

The burns produced by electrical accidents are very dangerous.

 

The factors are: 

INTENSITY

The electrical intensity that happens through the human body, together with the time of circulation, is the determining cause of the gravity in the electrical circuit.

This verified that intensities between:

1 - 3m.A. Do not offer danger some and its contact can be maintained.

3 - 25m.A. They can give rise to:

- Muscular contractions.

- Difficulty to separate of the meeting point.

- Burns.

- Secondary dangers.

- Increase of the sanguineous tension.

25 - 75m.A. They can give rise to:

- Shutdown of respiratory muscles (asphyxia).

- Ventricular fibrilación (time of greater contact of 3 minutes).

- Collapse.

75 - 3000m.A. It causes:

- Total Paralysis of breathing.

- Irreversible ventricular Fibrilation.

Mayor de 3A can produce ventricular fibrilación and great burns.



The asphyxia is one of the serious consequences but of the electrical accidents.

  

RESISTANCE

The electrical intensity that circulates around the human body because of an accidental contact, will exclusively depend only and on the resistance that is offered to the passage of the current, being this resistance the sum of:

- Resistance of the meeting point (skin).

- Resistance of the internal weaves that crosses the current.

- Resistance of the zone of exit of the current.

The meeting point with the tension source is always the skin, and its resistance can vary between 100 ohms for fine and humid skin and 1000000 ohms in rough and dry skin, internal weaves 500 ohms.

In most of the cases, the zone of exit of the current they are the feet, so the resistance will also depend on the type of footwear and the material of which the this made ground.



The electrical accidents can be produce for a bad conection of the anything of electrical apparatuses that you have in your house.

 

CONTACT TIMES

Aproxymate numbers so that ventricular fibrilación gets to take place:

- 15 m.A. during 2 minuts.

- 20 m.A. " 1 minut.

- 30 m.A. " 35 seconds.

- 100 m.A. " 3 seconds.

- 500 m.A. " 0,10 seconds.

- 1 A " 0,03 seconds.

ventricular fibrilación del is anarchical contractions cardiac muscle that takes place by the passage of the electrical current of a certain intensity and duration to traverse del heart.

 

TENSION 

Considering, that smaller intensities of 25m.A. they do not cause serious upheavals to the organism, and that the human resistance is of 1000 to 2000 ohms, we will have like tension of electrical security the following one:

- 0,025 * 1000 = 25V conductive or humid atmosphere.

- 0,025 * 2000 = 50V in dry atmosphere.