Electrical Safety FRUMENCIO T. TAN Accredited Safety Consultant
Oct 30, 2014
Electrical Safety
FRUMENCIO T. TANAccredited Safety Consultant
Electricity - The Dangers
About 5 workers are electrocuted every week
Causes 12% of young worker workplace deaths
Takes very little electricity to cause harm
Significant risk of causing fires
Electricity – How it Works
Electricity is the flow of energy from one place to another
Requires a source of power: usually a generating station
A flow of electrons (current) travels through a conductor
Travels in a closed circuit
BASIC ELECTRICAL TERMS
What are the definitions of these terms?
Electricity
Current
Voltage
Resistance
Amps
Volts
Ohms
Direct current
Alternating current
Conductor
Insulator
Electrical Injuries
There are four main types of electrical injuries:
Direct:Electrocution or death due to electrical shockElectrical shockBurns
• Indirect - Falls
RESISTANCE OF THE HUMAN BODYTO DIFFERENT AMPERAGES
8 - 15 m.a. - Pain 15 - 20 m.a. - Pain, loss of muscular
control 20 - 100 m.a. - intense pain and paralysis
of breathing muscles; - possible suffocation.
100 - 200 m.a. - Ventricular fibrillation which will cause death.
Over 200 m.a. from 220V household voltage
Defibrillator in use
Burns
Most common shock-related injury
Occurs when you touch electrical wiring or equipment that is improperly used or maintained
Typically occurs on hands
Very serious injury that needs immediate attention
Electrical Burns
Entrance Wound
Exit Wound
Arc or Flash Burns Thermal Contact Burns
Internal Injuries
Involuntary Muscle Contraction
Current flows through the body from the entrance point,until finally exiting where the body is closest to the ground.
AVOID THE FOLLOWING UNSAFE ACTS:
Worker’s attitude such as working without appropriate PPEs.
Improper working method
Wearing of metal objects as watches, necklaces & rings.
Working in wet and/or damp locations
AVOID THE FOLLOWING UNSAFE ACTS:
AVOID THE FOLLOWING UNSAFE ACTS:
AVOID THE FOLLOWING UNSAFE ACTS:
Failure to de-energize, lockout and tagout hazards during maintenance, repair or inspections of fuse box.
Use of defective and unsafe tools.
Use of tools or equipment too close to energized parts.
Not draining off stored energy in capacitors.
Double Insulated Tool
AVOID THE FOLLOWING UNSAFE ACTS:
Using 3 wire cord with a 2 wire plug.
Remove and replace wrong fuse.
Not verifying power is off when making repair.
UNSAFE EQUIPMENT
What equipment can cause electrical accidents:
Faults in facilities such as exposed charged part of electrical machines and equipmentDamaged insulation of electrical wiringsShort CircuitOverloadingImproper grounding
HAZARDOUS ENVIRONMENT
Flammable vapors, liquids and gases
Combustible dusts
Corrosive atmosphere
Explosive environments
HAZARDOUS ENVIRONMENT
Deteriorated cords, where the exterior insulation has cracked, exposing the wires inside.
Cords and/ or plugs produced from substandard materials.
Use of cords which have no appropriate current (amp) rating for either the plug or the equipment.
HAZARDOUS ENVIRONMENT
Use of extension cords for permanent installations.
Equipment which has been incorrectly wired, representing either a shock or fire hazard.
ELECTRICAL HAZARDS TO WATCH OUT FOR
Loose electrical connectionsCord with frayed insulationsPlugs that do not match their outlets, e.g., 3-prong male plug to 2-plug female outletNon-waterproof cords, plugs and outlets used outdoorsEquipment running over capacity
ELECTRICAL HAZARDS TO WATCH OUT FOR
Tools that smell, smoke, spark or shockWires running across the floorElectrical cords in contact with hot appliances or soaked in waterExtension cords instead of permanent wiringOctopus connections
Electrical Plugs and Extension Cords
Electrical Plugs and Extension Cords
MEASURES TO PREVENT ELECTRIC SHOCK
Use grounding systemInstall GFCIIsolation of electrical conductors
Vault & boxesWarning signs
Safe ClearanceElevation (at least 10 ft minimum) of electrical cable specifically at construction siteMinimum approach distance
PREVENTIVE MEASURE ON ELECTRIC SHOCK
InsulationUse double-insulated royal cord for toolsProvide good insulation for appliancesInsure insulation between feet and moist ground
Use appropriate PPEUse Lock-Out and Tag-OutJHA
GROUNDINGParticulars regarding details of conductors sizes & nature of grounds can be obtained from the provision of the Philippine Electrical Code governing them
GROUNDING ROD SPECIFICATIONSteel Rod - 5/8” dia. & 8 ft longCopper Clad Steel Rod - 1/2” dia. & 8 ft longGalvanized Pipe - 3/4” & 8 ft longResistance should not exceed 25 ohms
Ground Fault Circuit Interrupters
Portable Ground Fault Circuit Interrupters
GFCI Panel Mounts
Preventing Electrical Hazards - PPE
Proper foot protection (not tennis shoes)
Rubber insulating gloves, hoods, sleeves, matting, and blankets
Hard hat (insulated - nonconductive)
SIMPLE RULES TO FOLLOW
DO NOT GUESSUSE PROPER INSTRUMENTSALWAYS USE SAFETY DEVICESLOCKING & TAGGING PROCEDURENEVER WORK ALONEUSE DANGER SIGNS
THANK YOU ALL!