Electrical Safety Awareness
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Transcript of Electrical Safety Awareness
Electrical Safety Awareness
TrainingRakib Hossain
Maintenance EngineerMidas Safety Bangladesh
Training Outline
•Basic Concepts of Electricity•Hazard Recognition•Effects of Electricity on the Human Body•Electrical Hazard Protection•Work Practices•How to Respond/Report a Problem•Supervisor Responsibilities•Video
Basic Concepts of Electricity• flow of electrons
(current) through a conductor.• Requires - source of
power• Travels in a closed
circuit.• When you become part
of the circuit – injury occurs.
Hazard Recognition• Cords & Equipment
• Power tools and extension cords inspection.
• If broken insulation servicing without delay.
Hazard Recognition• Cords & Equipment
• Visual InspectionVisual Inspection.
• Worn and damaged wire must be replaced without delay.• • Before cleaning - turn it off and unplug it.
Hazard Recognition• Electrical Panels
• Keep clear and no obstacles infront of it.
• No storage in panel room.
Hazard Recognition• Trip Hazards
• tripping hazards or create pinch
points for cords.
• Running a cord temporarily across the floor-- create protection
Hazard Recognition• Exposed Wiring
• Assume all exposed wiring is energized until proven otherwise.
• protect the area - contact supervision .
Hazard Recognition• Power Strips• daisy chain multi-outlet strips (plugging into
each other)
Hazard Recognition• Junction boxes, pull boxes,
and fittings – Covered.
• Unused openings in cabinets, boxes, and fittings- Closed.
• Report these situations to your supervisor.
Effects of Electricity on the Human Body• The four major types of electrical injuries
are:• Direct• Electrocution• Electrical Shock• Burns
• Indirect• Falls
Effects of Electricity on the Human Body: Electrical Shock• Received when current
passes through the body.• Severity of the shock
depends on:
• Path of current through the body.
• Amount of current.
• Length of time the.
Effects of Electricity on the Human Body: Electrical Shock• Range of currents lasting 1 second will illicit the
following reactions: • 1 milliamp• Just a faint tingle.
• 5 milliamps• Slight shock felt. Most people can let go.
• 6-30 milliamps• Painful shock. Muscular control is lost. This is the
range were “freezing current” starts. It may not be possible to let go.
Effects of Electricity on the Human Body: Electrical Shock• 50-150 milliamps• Extremely painful shock, respiratory arrest,
(breathing stops) and severe muscle contractions. Death is possible.
• 1,000-4,300 (1-4.3 amps)• Arrhythmic heart pumping action, muscles contract,
and nerve damage occurs. Death is likely.
• 10,000+ milliamps (10 amps)• Cardiac arrest and severe burns occur. Death is
probable.
Effects of Electricity on the Human Body: Electrical Shock• exposure, danger of shock • Low voltage can be extremely dangerouss because
the degree of injury depends not only on the current, but on the length of time in contact with the circuit.• Example:• A current of 100mA applied for 3 seconds is as
dangerous as 900mA applied for 0.03 seconds. • Low Voltage Does Not Mean Low Hazard.
Effects of Electricity on the Human Body: Electrical Shock•High voltages additional injuries.• Violent muscular contractions• May cause bone fractures from either
contractions themselves or from falls.
• Internal bleeding, destruction of tissues, nerves and muscles.
Effects of Electricity on the Human Body: Electrical Burns• Common nonfatal injury burn.• Burns caused by electricity may be of three types:• Electrical burns• Arc burns• Thermal contact burns
• Electrical burns immediate medical attention.
Effects of Electricity on the Human Body: Falls• Electric shock can also
cause indirect injuries. • Elevated workplace –
Fatal Injury.
Electrical Hazard Protections• Insulation•Grounding•Guarding• Electrical protective devices• Personal Protective Equipment• Safe work practices
Electrical Hazard Protections• Insulation
• Plastic or rubber coverings.
• Prevents live wires from coming in contact with people.
Electrical Hazard Protections• Grounding • Grounding is another
method.
• However, it is normally a secondary protective measure.
• By "grounding" a low-resistance path to the earth is intentionally created.
Electrical Hazard Protections• Guarding• A type of isolation .
• These structures include:• Boxes• Screens• Covers• Partitions
Electrical Hazard Protections• Fuses and Circuit Breakers• Intended primarily for the protection of
conductors and equipment.
• They prevent over-heating of wires .
• Also open the circuit under certain hazardous ground-fault conditions.
Electrical Hazard Protections• Personal Protective
Equipment• Foot protection • Footwear will be marked
“EH” if it’s approved for electrical work.• EH = Electrical Hazard• Footwear must be kept
dry.
Electrical Hazard Protections• Personal Protective
Equipment•Head protection• Hard hat (insulated -
nonconductive)• Class B & E.• Always wear your hat
with the bill forward.• Do not store anything
in the top of your hat while wearing it.
Electrical Hazard Protections• Personal Protective
Equipment•Hand protection• Rubber insulating gloves.
• Classified by the level of voltage and protection they provide.
Work Practices• Employees and others working with electric
equipment need to use safe work practices.
• Lock out and Tag out circuits and equipment.
• Shut off the circuit.• Lock and tag out the circuit at the distribution panel.• Test the circuit to make sure it’s de-energized.
Work Practices• Do not work in wet conditions.
• Avoid overhead power lines.(At least 10 feet high)
• Use proper wiring and connectors• Avoid overloading circuits.
• Test GFCI’s monthly.
• Make sure switches and insulation are in good condition.
How to Respond/Report a Problem•Do not panic; remain calm• In the event of a personal injury:• Call HSE personnel immediately.
• If a person is being shocked, turn of the source of electricity
• Do not touch someone being shocked
• Notify your supervisor
How to Respond/Report a Problem
• In the event of an electrical fire:• Activate the fire alarm system
• Do not use a Type A, water extinguisher
• If you know how to use an extinguisher, use a CO2 or dry chemical fire extinguisher
• If you are not sure about using a fire extinguisher, leave the area .
• Wait for the Fire Dept. personnel to arrive
Supervisor Responsibilities• Review project carefully with your workers, unless they
are routine assignments
• Emphasize safety practices
• Train workers on area-specific policies and procedures
• Check your employees’ work practices to ensure compliance
Video