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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.
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