Electrical Safety and methods used to control accidents

1. ELECTRICAL SAFETY & METHODS
USED TO CONTROL ACCIDENTS
NIT CALICUT
Presented By
V.Reshma
P.Harika
N.Priyanka
Harshid

2. ELECTRICAL HAZARDS
• Electricity is the second leading cause of death.
• Electrocutions make up 12% of fatalities annually.
• Harmful Effects of Electricity :
- Electric shock
- Burns
- Arc blasts

3. Electrical shock
 Most common and possibly causing electrocution or muscle contraction
leading to secondary injury.
 Electric shock occurs when the body becomes part of an electrical circuit
 Shocks can happen in three ways. A person may be in
i. Contact with both conductors
ii. Contact with one conductor and ground
iii. Contact with ground and an ungrounded conducting material.
 Severity of the shock depends on:
- Path of current through the body
- Amount of current flowing through the body
- Length of time the body is in the circuit

4. Burns
An arc occurs when there is a gap
between conductors and current
travels through the air.
• Arc burns
• Electrical burns
• Thermal contact burns
Thermal contact burns can occur
when electricity ignites
combustible material.
Electrical burns can occur
when you come into direct
contact with electricity.
Burns can result when a person touches electrical wiring or
equipment that is energized

5. Arc blast
 Arc-blasts occur from high-amperage currents arcing through
the air.
 Occurs in milliseconds
 Temp: 30,000 degrees
 Air expands very violently (15 tons of pressure)
 Effects of arc blast:
Severe burns, Broken bones, Vision damage, Hearing loss,
internal injuries, Death

6. Electrical Hazards
To avoid injuries, you should be aware of electrical hazards.
Some of the most common causes of electrical hazards are:
 Exposed electrical parts
 Overloaded circuits
 Defective insulation
 Improper grounding
 Damaged power tools
 Overhead power lines
 Wet conditions

7. Controlling Electrical Hazards
Employers must follow the
OSHA Electrical Standards (Subpart K)
Subpart K includes four proactive methods:
Electrical Isolation
Equipment Grounding
Circuit Interruption
Safe Work Practices

8. Electrical Isolation
We can be safe by keeping electricity away from us. We
can:
Insulate the conductors.
 Check the insulation on equipment and cords before plugging them in.
 Rubber and plastic is put on wires to prevent shock, fires, and short circuits.
 Remember, even the smallest defect will allow leakage!
Elevate the conductors.
 To check the location of overhead lines.
 Never allow yourself, your tools, or the materials you are working with be
within 10 feet of energized lines.

9. Working Near Overhead Lines
Clearance of worker and any equipment, tool, material near
uninsulated lines
 Less than 50 kv : 10 feet.
 More than 50 kv : 10 feet + 0.4 inches for each kv.
Clearance near insulated lines
 Less than 300 kv : 3 feet.
 300 to 500 kv : 10 feet.
Cranes, Derricks, Hoists
 50 kv or less : minimum 10 feet.
 More than 50 kv : 10 feet + 0.4 for each kv.

10. Guard the conductors by enclosing them.
 Covers, boxes & enclosures are put around conductors to avoid contact
with workers.
 Check that electrical boxes and panels are covered and free from
missing “knock-outs”.
 Electric equipment operating at 50 volts or more must be guarded.

11. Equipment Grounding
 We can be safe by providing a separate, low resistance pathway for
electricity when it does not follow normal flow.
 Grounding gives the stray current somewhere to go and keeps you
from becoming part of the circuit.
 Grounding will not work if the electricity can flow through you more
easily than the ground.
This can happen when:
 Your tool doesn’t have a ground pin.
 You’re working in water.
 You’re touching a metal object.

12. Circuit Interruption
We can be safer by automatically shutting off the flow
electricity in the event of leakage, overload, or short
circuit.
Fuses, circuit breakers, & Ground Fault Circuit
Interrupters (GFCI) are circuit protection devices.
Remember, circuit breakers & fuses protect equipment,
not you, because they take too much current & too much
time to trip.

13. You can StartSafe and StaySafe by using the following safe work
practices:
Safe Work Practices
 Inspect cords before each use
 Never overload a circuit
 Stay away from all unguarded conductors
 To unplug, pull on the plug, not the cord
 Don’t wear jewelry or use other metal objects around
electrical equipment

14. Training concerning electricity is very important. Training for
employees working with electrical equipment must include
how to:
 De-energize the equipment
 Use lockout and tag procedures
 Use insulating protective equipment
 Maintain a safe distance from energized parts
 Use appropriate PPE
Safe Work Practices: Training

15. When performing lockout/tagout on circuits, trained employees
will do the following:
Safe Work Practices: Lockout/Tagout
 Turn off the power supply
 Put a lock on all power sources to the circuit
 Apply a tag
 Test the circuit

16. Summary
 Know the hazards
 Plan your work and plan for safety
 Avoid wet working conditions and other dangers
 Avoid overhead power lines
 Use proper wiring and connectors
 Use and maintain tools properly
 Wear the correct PPE for the job

17. THANK YOU