ELECTRICAL SAFETY & METHODS USED TO CONTROL ACCIDENTS

NIT CALICUT

Presented ByV.ReshmaP.HarikaN.PriyankaHarshid

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

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

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

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

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

Controlling Electrical HazardsEmployers must follow the OSHA Electrical Standards (Subpart K)

Subpart K includes four proactive methods:Electrical IsolationEquipment GroundingCircuit InterruptionSafe Work Practices

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.

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.

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.

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.

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.

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

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

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

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

THANK YOU