Safety in Electronics

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Section 1
Safety in Electronics
 2013
Fertilizer plant explosion near Waco,
Texas

http://www.youtube.com/watch?v=Ba8jTkRWiwI
 2013
Rana Plaza factory building collapse near
Dhaka, Bangladesh

http://www.youtube.com/watch?v=poQoWBSgiEA
 2011
Fukushima Daiichi nuclear disaster in
Japan

http://www.youtube.com/watch?v=8c2GN63HUhM
 In
general, an accident is an unplanned and
unexpected event that interferes with the
activity a person is engaged in. An accident
may lead to an injury to the person directly
involved; it may also lead to the injury of
others.
 When
an accident occurs, you can never be
sure of the outcome. The result of an
accident can range from a minor irritation to
a major injury and even death.
 Accidents
a cause.
 For
do not just happen. They all have
example, a person can easily cause an
accident by repairing electrical equipment
while it is still hooked up to power. The
question to ask of a person doing this type of
activity is not whether an accident will
happen, but when the accident will occur,
because sooner or later the worker will touch
a live wire (if the worker continues doing this
type of activity).
 It
would not be truthful to say, ”Look, an
accident happened to that worker.” It would
be more appropriate to say, “Look, that
worker just caused an accident.”
 http://www.youtube.com/watch?v=aXRe0HY
AUeU
 http://www.youtube.com/watch?v=DX1iplQQ
JTo
 http://www.youtube.com/watch?v=FZrkaZxuYU
 An
unsafe act is anything a worker does that
does not follow accepted, normal, or correct
procedure or practice. Unsafe acts lead to
accidents.
 An unsafe condition is any hazardous
physical condition, which if left uncorrected,
can lead to an accident.
 You must recognize and identify unsafe acts
in order to remove them. The better you are
at recognizing dangerous acts and conditions,
the less accident-prone you will be.
 Failing
to wear safe attire is considered an
unsafe act. Without proper clothing, a person
soldering an electronics project could
receive a severe burn if a drop of molten
solder landed on him or her.
 Distracting, teasing, abusing, or startling
someone are all unsafe acts. Distractions
prevent people from concentrating on what
they are doing and can cause injuries like a
burn from touching a hot soldering iron.






Operating equipment without warning people in the
area (for example, using a soldering iron creates toxic
fumes).
Operating equipment before checking out its condition
(for example, a power tool might have a short circuit)
Operating equipment before securing accessories (for
example, saw blades or drill bits should be tightly
secured)
Failing to shut off equipment that is unattended (for
example, a soldering iron left plugged in could seriously
burn someone or start a fire. Operating equipment in an
unsafe environment (for example, using a soldering iron
near flammable material.
Working with, or near equipment after taking drugs,
alcohol or any medication (prescription or nonprescription) that can make you dizzy or sleepy.
Working on equipment that is still connected to a power
source.




Defective equipment make working conditions unsafe.
Extension cords with damaged insulation are dangerous,
especially in wet conditions. Equipment or cords with
exposed live wires are extremely dangerous.
Improper ventilation in the work area is unsafe. Fumes
from the materials being worked on to remain in the
work area making it unsafe (for example, solder and flux
fumes).
Wet work areas are a hazard. Do not work around or
with equipment if the floor is wet. It is easy for you
and/or your equipment to slip if the work area is wet.
The wet area could also be a dangerous (toxic)
substance. Power equipment should never be used
outdoors after a rain until the ground has dried.
Portable power equipment must be grounded or it be of
the double-insulated type. Double-insulated tools have
an insulating case so the operator does not touch any
parts that could give him or her a shock.

To reduce accidents, you must work to remove the
causes. Overconfidence can lead to accidents.


Have you ever seen a car slide on a slippery ice patch
and then, once recovered, take off as if nothing has
happened? If the driver of this car did not learn from the
experience and continued the unsafe driving (unsafe
acts), he or she could cause a serious accident.
Accident prevention also means considering and
acknowledging your own limitations before
attempting a job.

For example, you should never attempt to lift an object
if you are not strong enough. If you move material from
a shelf, but you cannot hold it because it is too heavy,
you could easily develop a back, leg, or foot injury.
 The
possibility of injury from shocks or burns
always exists when working with electrical
equipment. Develop attitudes and habits that
maintain safety as a first priority to prevent
injuries. Mistakes and carelessness may
result in injury to you or someone else. It is
therefore important to have some knowledge
about first-aid practices.
Contact with a live or bare wire/cable or a stoke
of lightening can cause electrical current to pass
through the body. This can cause severe,
potentially fatal injury, depending on the
amount of current, its path through the body and
the duration of contact.
 There are two main types of electrical injuries:

Shock
 Burns


Electrical injuries can occur anywhere electricity
is being used to power appliances or machines.
Overhead, high-voltage supply lines can also
cause injuries.

The following chart lists some of the possible effects of
electric shocks received by the passage of various
current values.

The current values are given in milliamperes (1/1000 A or
0.001 A). These values are very small when you consider
the average outlet in the home is fully capable of delivering
15 amperes (15 000 milliamperes).
 Burns
may be severe and deep, especially
with higher voltages. With any heat burn the
skin is usually destroyed. The burn
penetrates into the flesh beneath the area in
direct contact with the burn. In the case of
an electrical contact burn, the destruction of
the flesh fans out into the body. A section of
the destroyed tissue is cone-shaped,
spreading out from the surface of the burn.
As a result, it is very difficult to determine
the seriousness of an electrical contact burn
simply by examining the surface area.






Work areas that involve the use of tools that generate heat,
such as soldering irons, should have a fire extinguisher close
by.
If a fire occurs, always call the fire department first. Alert
anyone else working in the area.
Do not attempt to put out the fire unless you are absolutely
sure you can contain it. Some fires may be easily put out if
you respond quickly, while a fire is just beginning to flare up.
Become familiar with the fire extinguishers around you. Read
the directions on each fire extinguisher before you have to use
it; the types of fires it can be used on will be given.
Some types of fire extinguishers, such as dry chemical
extinguishers and carbon dioxide extinguishers, can be used
on flammable liquids without spreading the fire and without
fear of electrocution.
Water is one of the best fire-fighting agents if it is used on
appropriate types of fires. Water can be used to extinguish
fires in wood and paper, as long as there are no electrical
wires close by. Electricity can conduct back along the water
and possibly electrocute the person fighting the fire if
electrical wires are involved.



Respond immediately after an accident occurs.
Emergency response should be made available as
quickly as possible. A person's injuries could quickly
get worse if emergency treatment is not carried out
immediately. If there is a serious injury, is important
to call for an ambulance as quickly as possible.
If a person has come in contact with high voltage, do
not attempt to touch him or her until you are sure
the power is off. Touching a person or vehicle or
machine still in contact with live wires could get you
electrocuted.
First-aid supplies should be available wherever work
is taking place. Minor cuts and other injuries should
be treated to prevent infection. If there is any doubt
as to the seriousness of an injury, visit a doctor as
soon as possible
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