This document provides an overview of electrical safety training. It defines key electrical terms and describes the effects of electric shock on the human body. Hazards of electricity include burns, electrocution, and shock. The severity of electric injuries depends on current, path through the body, duration of contact, and energy type. Basic safety measures include ensuring equipment is de-energized during work, using proper PPE and grounding, and following lockout/tagout procedures. Signs of electric shock include muscle spasms, burns, pain, cries, and loss of consciousness. Cardiopulmonary resuscitation (CPR) is important if breathing is impaired by an electric shock until medical help arrives.

1. TRAINING MODULE
Electrical Safety

2. 2

3. CONTENTS:
• Glossary of Terms:
• Effect of electric shock on human body
• Human Resistance to Electrical Current:
• Electrical Hazard
• Signs & Symptoms of Electric Shock:
• Cardio pulmonary resuscitation (CPR)

4. Glossary of Terms:
Current: The movement of electrical charge.
Voltage: A measure of electrical force (You will receive a shock if you touch two wires at
different voltages at the same time)
Resistance: A material's ability to decrease or stop electrical current.
Neutral: At ground potential (0 volts) because of a connection to ground. (You will receive
a shock if you touch alive wire and are grounded at the same time)
Ohm: Unit of measurement for electrical resistance. Circuit: A complete path for the flow of
current Ground: A physical electrical connection to the earth Fault current: Any current
that is not in its intended path.
Leakage current: Current that does not return through the intended path but instead
“leaks‖ to ground.

5. Conductor: Material in which an electrical current move easily
Energized (live, “hot”): Similar terms meaning that a voltage is present that can cause a current
De-energize: Shutting off the energy sources to circuits and equipment and depleting any stored
energy
Amperage: Strength of an electrical current, measured in amperes.
Ampere (amp): The unit used to measure current.
Mill ampere (milliamp or mA): 1/1,000 of an ampere. Lock-out: Applying a physical lock to the
energy sources of circuits and equipment after they have been shut off and de-energized.
Ground potential: The voltage a grounded part should have; 0 volts relative to ground.
Power: The amount of energy used in each second, measured in watts.
1 horsepower = 746 watts
Tag-out: Applying a tag that alerts workers that circuits and equipment have been locked out

6. Shocking current: Electrical current that passes through a part of the body. Severity of shock depends on
voltage, amperage, and resistance.
Bonding: Joining electrical parts to assure a conductive path Bonding
jumper: conductor used to connect parts to be bonded
Short: Low-resistance path between a live wire and the ground or between wires at different voltages(called
a fault if the current is unintended)
Ground fault: A loss of current from a circuit to a ground connection. Double-insulated: Equipment with
two insulation barriers and no exposed metal parts
Overload: Too much current in a circuit. Double-insulated: Equipment with two insulation barriers and no
exposed metal parts
Fixed wiring: Permanent wiring installed in homes and other buildings
Flexible wiring: Cables with insulated and stranded wire that bends easily
Guarding: Covering or barrier that separates you from live electrical parts

7. Insulation: Material that does not conduct electricity easily. Make sure insulation is the right type and in
good condition.
GFCI: Ground Fault Circuit Interrupter - a device that detects current leakage from a circuit to ground
and shuts the current off. GFCI‘s have their limitations. An electrical circuit in a damp place without a
GFCI is dangerous. A GFCI reduces the danger.
Over current protection device: device that prevents too much current in a circuit An overload can
lead to a fire or electrical shock.
Circuit breaker: An over current protection device that automatically shuts off the current in a circuit if
an overload occurs.
ELCB: Earth Leakage Circuit Breaker - protective device used for ground fault protection. The rating of
the ELCB shall be 30mA with the fault clearing time less than 500 ms or 100mA with fault clearing time
less than 100 ms.
Trip: The automatic opening (turning off) of a circuit by a GFCI or circuit breaker.
Fuse: An over current protection device that has an internal part that melts and shuts off the current in a
circuit if there is an overload.

8. Fuse: An over current protection device that has an internal part that melts and shuts off the current in a
circuit if there is an overload.
CPR: Cardio Pulmonary Resuscitation: Emergency procedure that involves giving artificial breathing and
heart massage to someone who is not breathing or does not have a pulse (requires special training).
NEC: National Electrical Code - Comprehensive listing of practices to protect workers and equipment from
electrical hazards such as fire and electrocution
Electrical injuries may occur anywhere. It may be caused by direct current (DC) or by lightening. The
severity of the injuries by electric shock depends upon:
• The amount of current flowing through the body.
• The path of current has flown through the body to the earth. A weaker current passing through heart is
more dangerous than a relatively stronger current passing through any other parts of the body.
• Length of time the victim is in contact.
• Type of electrical energy.

9. Effect of Electricity on Human Body
9
Time
GFCI
GFCI – Ground-Fault Circuit Interrupter
ELECTROCUTION
PREVENTION

10. Human Resistance to Electrical Current:
Body Area Resistance (ohms)
Dry Skin 100,000 to 600,000 Ohms
Wet Skin 1,000 Ohms
Internal body – hand to foot 400 to 600 Ohms
Ear to ear (about) 100 Ohms

11. Hazards of Electricity
Primary
• Burns
• Electrocution
• Shock
• Arc flash/arc
blast
Electricity is created when electrons flow through a conducting material,
such as the copper or aluminum used in power lines.
Secondary
• Fall from height
• Fire
• Explosions
Electrical Hazard:

12. Energy Sources:
These energy sources are hazardous when they come in direct contact with human being while
conducting service or maintenance.

13. Signs & Symptoms of Electric Shock:
a) Sudden spasm
b) Burn
c) Severe pain
d) Cries out loud and falls on the ground
e) Unconsciousness
f) Breathing impaired or stopped
g) Burns leading to severe surgical shock

14. Basic Safety Measures:
 No Job shall be carried out in any electrical room/installation without work permit from
authorized person of TCIL.
 All electrical connections to be routed through ELCB.
ELCB sensitivity shall be maintained at 30 mA. All the distribution boards to be earthed
and connected with ELCB.
 Personnel working around electrical equipment shall take precautions to ensure that the
equipment is de-energized while work is being conducted on or around such equipment.
 Work that is to be conducted near any overhead power line shall be planned so that the
clearance is not less than ten feet or as per IE rules.

15. If work is to be performed within 3.0m radius of overhead energized equipment, the
equipment must be de-energized prior to starting the work, unless adequately controlled by
the safe work system.
Ladders used around electrical equipment should be of non-metallic construction so as not
to be a conductor of electricity.
 Precautions should be taken to ensure that all equipment used is properly grounded and
that accidental contact with ungrounded electrical sources is prevented.
All welding machines must be properly earthed with the provision of adequate earth.
Industrial plug tops and sockets to be used for connection
Since the most common result of electrical accident is failure of the nervous which
controls breathing, it is important the victim be applied to cardiopulmonary resuscitation
(CPR).
The technique should be continued until victim is revived or death is diagnosed by a
physician.

16. Cardio pulmonary resuscitation (CPR)
• Cardiopulmonary resuscitation is a lifesaving technique useful in many emergencies
including cardiac arrest due to electric shocks.
• Cardiac arrest is often caused byan abnormal heart rhythm called ventricular fibrillation
(VF). When VF develops, the heart quivers and does not pump blood. The victim in VF
cardiac arrest needs CPR and delivery of a shock to the heart, called defibrillation.
Defibrillation eliminates the abnormal VF heart rhythm and allows the normal rhythm to
resume.
• CPR involves a combination of mouth-to-mouth rescue breathing and chest compression
that keeps oxygenated blood flowing to the brain and other vital organs until more
definitive treatment can restore a normal heart rhythm.
When the heart stops, the absence of oxygenated blood can cause irreparable brain
damage in only a few minutes. Death will occur within 8 to 10 minutes.