Department Of Pharmaceutics
Under The Guidance Of:
Dr.Jagadeesh Induru M.Pharm ,M.B.A, PhD
Mrs. Tripti Suxena M.Pharm
Types of current
Dangers of electricity to the living tissue
Conditions that effect the shock
Saving the electrified person
Protection against electrical hazards
Electric hazard control
Things to be avoided
Regular safety Inspection
An electrical hazard can be defined as
- a dangerous condition where a worker could make electrical
contact with energized equipment or a conductor, and from which
the person may sustain an injury from shock
The law requires safe work practices. Under
the Occupational Health and Safety Act and
Regulations for Construction Projects,
employers, supervisors, and workers each
have legal responsibilities to ensure that work
is being carried out in a safe manner.
Electrical hazards are caused by
❑ The improper use of machinery or apparatus
❑ The improper use of electrical outlets
❑ The improper use of electrical equipment, such as cables and power
❑ The improper maintenance of apparatus, outlets, and electrical
Basically, electrical hazards can be categorized into three types.
The first and most commonly recognized hazard is electrical shock.
The second type of hazard is electrical burns and the third is the
effects of blasts which include pressure impact, flying particles
from vaporized conductors
Both alternating current (AC) and direct current (DC) can produce
injury to living tissue and can destroy equipment. However, the AC (60
Hz and 120 V) that electric companies supply to most electrical outlets
disturbs human nerve impulses more readily than DC of the same
voltage or AC at other frequencies do because human nerve impulses
resonate at approximately 60 Hz. In addition, the DC circuits often used
in classroom experiments are relatively harmless. Yet, DC can still be
dangerous, and burn hazards are created in many common uses of DC.
So, all circuits should be treated cautiously.
Electrical hazards can burn equipment and cause a fire. These hazards can
also cause serious injuries. Specifically, current passing through a body may
produce one or more of the following symptoms:
Shock should not be confused
with electric shock. Shock is
an excitation or disturbance
of the normal function of
nerves or muscles.
Involuntary muscle reaction
A person who experiences an
electric shock may not be able to
control the muscles, such as the
heart, may operate abnormally.
An electric shock may
prevent muscles from
moving (for example,
arm muscles cannot
flex) or operating (for
example, the heart
cannot pump blood).
Burning of tissue and organs
Tissue and organs may be burned so
badly that they haemorrhage.
Death can result from electrocution,
which is caused by electric shock. 6
Electric shock occurs when the body becomes part of an electrical
circuit. Shocks can happen in three ways.
• A person may come in contact with both conductors in a circuit.
• A person may provide a path between an ungrounded conductor
and the ground.
• A person may provide a path between the ground and a
conducting material that is in contact with an ungrounded
An electric shock can injure you in either or both of the following.
• A severe shock can stop the heart or the breathing muscles, or both.
• The heating effects of the current can cause severe burns, especially
at points where the electricity enters and leaves the body.
Current in milli amperes Effects
1 or less No sensation; probably not noticed
1 to 3 Mild sensation not painful
3 to 10 Painful shock.
10 to 30 Muscular control could be lost or
30 to 75 Respiratory paralysis
75mA to 4 amps Ventricular Fibrillation
Over 4 amps Tissue begins to burns. Heart
muscles clamp andheart stops
Effects of Electrical Current On the Human Body
CURRENT PATH THROUGH THE BODY
Electric shocks are less severe if the current path does not include
LENGTH OF TIME THE ELECTRIC SHOCK ACTS ON THE BODY
The duration of the electric shock effects the extent of injury the
longer the duration of the electric shock on the body, the greater
risk of severe injury. In addition, the electric shock can influence
the duration of exposure if a victim cannot let go of the conductor
of electricity that is causing the electric shock because of loss of
voluntary muscle control
❑ LOCATION ON THE BODY OF THE ELECTRICAL CONTACT
An electric shock that starts at a finger and exits through the grounded
elbow on the same arm will do less damage than an electric shock that
starts at a finger and exits through the victim’s grounded feet.
The latter scenario is more dangerous because more tissue is affected and
the path of current is closer tointernal organs.
Current can burn vital organs even if the current does not pass through
those vital organs.
This type of damage may occur externally because of arcing or thermal
contact (a vital organ is near tissue that is experiencing electric shock).
❑ SKIN RESISTANCE
The resistance of the body greatly affects the severity of the electric
Human tissue has very low resistance because the cellular fluid in
tissue is a good conductor of electricity.
However, dry skin has very high resistance where as Resistance of
wet skin is low.
Skin resistance is even lower than the resistance of wet skin if a
cut or deep abrasion is present.
The exposure of moist and deeper skin layers increases the severity
of injury that results from the electric shock.
If someone is electrified , call for emergency personnel.
Then, remove the person from contact with the energized
Do not try to touch the person or you may be electrified as well.
You can turn off the power of the device that is causing the
electric shock if this can be done safely (for example, turning off
the circuit breaker for the outlet in which the device is plugged).
Or you can obtain an insulator, such as a wooden meter stick,
and break the contact between the person who is being electrified
and the energized conductor.
After the person who is suffering from electric shock has been
removed from the source of the shock, check to see if this person is
having breathing problems or is experiencing ventricular fibrillation.
Artificial respiration or cardiopulmonary resuscitation should be
performed on the person who experienced electric shock, if necessary.
Also, use blankets to keep the person warm.
Although a person who is electrified may appear unharmed, call
emergency personnel because this person may have suffered internal
injuries, such as burns to organs during the electric shock.
Most electrical accidents result from one of the following three
• unsafe equipment or installation,
• unsafe environment, or
• unsafe work practices.
Some ways to prevent these accidents are through the use of
insulation, guarding, grounding, electrical protective devices, and
safe work practices.
Insulators such as glass, mica, rubber, or plastic used to coat metals and
other conductors help stop or reduce the flow of electrical current. This
helps prevent shock, fires, and short circuits. To be effective, the insulation
must be suitable for the voltage used and conditions such as temperature
and other environmental factors like moisture, oil, gasoline, corrosive fumes,
or other substances that could cause the insulator to fail
Insulation on conductors is often colour coded.
Insulated equipment grounding conductors usually
are either solid green or green with yellow stripes.
Insulation covering grounded conductors is generally
white or gray. Ungrounded conductors, or “hot
wires,” often are black or red, although they may be
any colour other than green, white, or gray.
Grounding a tool or electrical system means intentionally creating a
low resistance path that connects to the earth.
This prevents the buildup of voltages that could cause an electrical
Grounding is normally a secondary protective measure to protect
against electric shock. It does not guarantee that you won’t get a shock
or be injured or killed by an electrical current.
A three pronged cord offers a grounding connection
White wire (neutral or common wire), returns the power.
Black wire (hot wire), is connected to the switch and fuse and carries
Green (or ground wire).
Three wires for each cord and terminal.
DO NOT use extension cords as permanent wiring. They
may not be able to carry the load. However, if it is necessary
to use an extension cord, never run it across walkways
Wall receptacles should be designed and
installed so that no current-carrying parts will
Replace or repair electrical appliances that over heated,
sparked, shorted out, smoked or have damaged cords or cracked
equipment If wires are exposed, they may cause a shock to a worker
comes into contact with them.
Cords should not be hung on nails, run over or wrapped
around objects, knotted or twisted. This may break the
wire or insulation.
Short circuits are usually caused by bare wires touching
due to breakdown of insulation.
Electrical tape or any other kind of tape is not adequate!
Pull the plug not the cord. Pulling the cord
could break a wire, causing a short circuit.
Plug your microwave or any other large appliances
into an outlet that is not shared with other
Do not overload circuits as this may cause the
wires to heat and ignite insulation or other
Keep office equipment properly cleaned and
Ensure lamps are free from contact with flammable
Be aware of the odor of burning plastic or wire.18
Water is VERY conductive! Overloading!
Missing grounding prong! 19
Missing outlet cover!
Electrical tape is not a fix! Damaged casing!
Don’t wear metal objects
Turn power off
Wear appropriate clothing
Don’t touch live parts
Don’t install or repair electrical equipment
Use qualified personnel
Clean and dry leads and plugs before use
Heed warning signs
Use the right equipment
Study the operation manual
Take care of extension leads
Use only approved extension lamps 21
Electrical equipment should be checked each time
before use for defects
If not tagged or the tag is out of date then report it and
place it out of service
The key messages are…
The risk of electric shock from correctly installed and maintained
power sources is negligible, provided that sensible precautions are
taken by the operator and correct work procedures are followed
Ensure that the right person is carrying out electrical work
Electricity is essential but, improperly used, it can be
TO STAY ALIVE, YOU HAVE TO STAY ALERT