Electrical safety and Arc Flash Training

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This presentation is part of the OSHA Focus Four training that I do in all my Construction courses. More information you can contact me: Larry@asctraininginc.net

Text of Electrical safety and Arc Flash Training

  • 1. Access Safety Compliance TrainingElectrical Hazardsin the Workplace29CFR1910 Subpart S

2. Instructor: Larry D. Rileywww.asctraininginc.comemail: larry@asctraininginc.comElectrical Hazardsin the Workplace 3. Cant Anticipate the unexpected http://www.hostedfile.com/videos/4081/pedestrian-hit-in-crash.htmlAccess Safety Compliance Training, Inc. 4. What we are going to cover Electricity what are the dangers? What is Electrical Shock? What is Electrical Burn? Hazards of electrical work. How to control them. Arc Flash: What are the Hazards? Grounding Why important? Safety-Related Work Practices Summary 5. Electricity - The Dangers About 5 workers areelectrocuted everyweek Causes 12% of youngworker workplacedeaths Takes very littleelectricity to causeharm Significant risk ofcausing firesAccess Safety Compliance Training, Inc.. 6. Electrical InjuriesThere are four main types of electricalinjuries:Direct:Electrocution or death due to electrical shockElectrical shockBurnsAccess Safety Compliance Training, Inc..Indirect - Falls 7. Electrical ShockAn electrical shock is received when electricalcurrent passes through the bodyYou will get an electrical shock if a part of yourbody completes an electrical circuit by Touching a live wire and an electrical ground,or By touching a live wire and another wire at adifferent voltage.Access Safety Compliance Training, Inc.. 8. Shock Severity Severity of the shock depends on: Path of current through the body Amount of current flowing throughthe body (amps) Duration of the shocking currentthrough the body LOW VOLTAGE DOES NOT MEANLOW HAZARDAccess Safety Compliance Training, Inc.. 9. Dangers of Electrical Shock Currents above 10 mA* can paralyze orfreeze muscles. Currents more than 75 mA can cause arapid, ineffective heartbeat -- deathwill occur in a few minutes unless adefibrillator is used 75 mA is not much current a smallpower drill uses 30 times as much* mA = milliampere = 1/1,000 of an ampereAccess Safety Compliance Training, Inc..Defibrillator in use 10. Burns Most common shock-relatedinjury Occurs when you touchelectrical wiring or equipmentthat is improperly used ormaintained Typically occurs on hands Very serious injury that needsimmediate attentionAccess Safety Compliance Training, Inc.. 11. My Friend BillInvolved in an arcflash whileworking! 12. Falls Electric shock can also causeindirect injuries Workers in elevatedlocations who experience ashock may fall, resulting inserious injury or deathAccess Safety Compliance Training, Inc.. 13. 2) Electrical Hazards and How toControl ThemElectrical accidentsare caused by acombination of threefactors: Unsafe equipmentand/or installation, Workplaces madeunsafe by theenvironment, and Unsafe work practices.Access Safety Compliance Training, Inc.. 14. Hazard Exposed Electrical PartsCover removed from wiring or breaker boxAccess Safety Compliance Training, Inc.. 15. Control Isolate Electrical PartsUseguards orbarriersReplaceall coversAccess Safety Compliance Training, Inc..Guard live parts of electricequipment operating at 50volts or more againstaccidental contact 16. Control Isolate Electrical Parts -Cabinets, Boxes & FittingsConductors going into them must be protected, andunused openings must be closedAccess Safety Compliance Training, Inc.. 17. Control Close Openings Junction boxes, pullboxes and fittingsmust have approvedcovers Unused openings incabinets, boxes andfittings must beclosed (no missingknockouts)Access Safety Compliance Training, Inc.. 18. Hazard - Overhead Power Lines Usually not insulated Examples of equipment thatcan contact power lines: Crane Ladder Scaffold Backhoe Scissors lift Raised dump truck bed Aluminum paint rollerAccess Safety Compliance Training, Inc.. 19. Hazard- Overhead Power Lines Stay at least 10 feetaway Post warning signs Assume that lines areenergized Use wood or fiberglassladders, not metal Power line workers needspecial training & PPEAccess Safety Compliance Training, Inc. 20. The story of a Power-lineInspector http://www.flixxy.com/helicopter-cable-inspector.htmAccess Safety Compliance Training, Inc. 21. Overhead Power linesAccess Safety Compliance Training Inc.. 22. TheSadRealityAccess Safety Compliance Training Inc.. 23. Hazard - Inadequate Wiring Hazard - wire too small for the current Example - portable tool with an extensioncord that has a wire too small for the tool The tool will draw more current than thecord can handle, causing overheatingand a possible fire without tripping thecircuit breaker The circuit breaker could be the rightsize for the circuit but not for thesmaller-wire extension cordAccess Safety Compliance Training, Inc.Wire GaugeWIREWire gauge measureswires ranging in size fromnumber 36 to 0 Americanwire gauge (AWG) 24. Control Use the Correct Wire Wire used depends on operation, building materials,electrical load, and environmental factors Use fixed cords rather than flexible cords Use the correct extension cordMust be 3-wire type and designed for hard or extra-hard useAccess Safety Compliance Training, Inc.1926.405(a)(2)(ii)(J) 25. Hazard Defective Cords & Wires Plastic or rubbercovering is missing Damagedextension cords &toolsAccess Safety Compliance Training, Inc. 26. Hazard Damaged Cords Cords can be damaged by: Aging Door or window edges Staples or fastenings Abrasion from adjacentmaterials Activity in the area Improper use can cause shocks,burns or fire1926.405(a)(2)(ii)(I)Access Safety Compliance Training, Inc. 27. Control Cords & Wires Insulate live wires Check before use Use only cords that are 3-wire type Use only cords marked for hard or extra-hardusage Use only cords, connection devices, andfittings equipped with strain relief Remove cords by pulling on the plugs,not the cords Cords not marked for hard or extra-harduse, or which have been modified, mustbe taken out of service immediatelyAccess Safety Compliance Training, Inc. 28. Permissible Use of Flexible CordsStationary equipment-tofacilitate interchangeDO NOT use flexible wiring wherefrequent inspection would bedifficult or where damage would belikely.Flexible cords must not be . . . run through holes in walls,ceilings, or floors; run through doorways, windows,or similar openings (unlessphysically protected); hidden in walls, ceilings, floors,conduit or other raceways.Access Safety Compliance Training, Inc. 29. GroundingGrounding creates a low-resistancepath from a tool tothe earth to disperseunwanted current.When a short or lightningoccurs, energy flows to theground, protecting you fromelectrical shock, injury anddeath.Access Safety Compliance Training, Inc. 30. Hazard Improper Grounding Tools plugged intoimproperly groundedcircuits may becomeenergized Broken wire or plugon extension cord Some of the mostfrequently violatedOSHA standardsAccess Safety Compliance Training, Inc. 31. Control Ground Tools & Equipment Ground power supply systems,electrical circuits, and electricalequipment Frequently inspect electrical systemsto insure path to ground is continuous Inspect electrical equipment beforeuse Dont remove ground prongs fromtools or extension cords Ground exposed metal parts ofequipmentAccess Safety Compliance Training, Inc. 32. Control Use GFCI (ground-fault circuitinterrupter) Protects you from shock Detects difference in current betweenthe black and white wires If ground fault detected, GFCI shuts offelectricity in 1/40th of a second Use GFCIs on all 120-volt, single-phase,15- and 20-ampere receptacles, or havean assured equipment groundingconductor program.Access Safety Compliance Training, Inc. 33. Control - Assured EquipmentGrounding Conductor ProgramProgram must cover: All cord sets Receptacles not part of a building or structure Equipment connected by plug and cordProgram requirements include: Specific procedures adopted by the employer Competent person to implement the program Visual inspection for damage of equipmentconnected by cord and plugAccess Safety Compliance Training, Inc. 34. Hazard Overloaded CircuitsHazards may result from: Too many devices pluggedinto a circuit, causing heatedwires and possibly a fire Damaged tools overheating Lack of overcurrentprotection Wire insulation melting,which may cause arcing and afire in the area where theoverload existsAccess Safety Compliance Training, Inc. 35. Control - Electrical Protective Devices Automatically opens circuit ifexcess current from overloador ground-fault is detected shutting off electricity Includes GFCIs, fuses, andcircuit breakers Fuses and circuit breakers areovercurrent devices. Whentoo much current: Fuses melt Circuit breakers tripopenAccess Safety Compliance Training, Inc. 36. Power Tool Requirements Have a three-wirecord with groundplugged into agroundedreceptacle, or Be double insulated,or Be powered by alow-voltage isolationtransformer Access Safety Compliance Training, Inc. 37. Tool Safety Tips Use gloves and appropriate footwear Store in dry place when not using Dont use in wet/damp conditions Keep working areas well lit Ensure not a tripping hazard Dont carry a tool by the cord Dont yank the cord to disconnect it Keep cords away from heat, oil, & sharp edges Disconnect when not in use and when changingaccessories such as blades & bits Remove damaged tools from useAccess Safety Compliance Training, Inc. 38. Preventing Electrical Hazards - Tools Inspect toolsbefore use Use the right toolcorrectly Protect your tools Use doubleinsulated toolsDouble Insulated markingAccess Safety Compliance Training, Inc. 39. Temporary LightsProtect fromcontact anddamage, anddont suspendby cordsunlessdesigned todo so.Access Safety Compliance Training, Inc. 40. Clues that Electrical Hazards Exist Tripped circuit breakers orblown fuses Warm tools, wires, cords,connections, or junctionboxes GFCI that shuts off a circuit Worn or frayed insulationaround wire or connectionAccess Safety Compliance Training, Inc. 41. ARC-FLASHWhat is an arc-flash?