Arc Flash Safety

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Arc Flash Safety. Qualified Persons Working On Or Near Energized Equipment. Objectives. You will be able to: Identify the causes and risks of arc flash Implement safe work procedures Identify and wear appropriate PPE Respond to an arc flash. What Is an Arc Flash?. - PowerPoint PPT Presentation

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  • Arc Flash SafetyQualified Persons Working On Or Near Energized Equipment

    Business & Legal Reports, Inc. 0709

    ObjectivesYou will be able to:Identify the causes and risks of arc flashImplement safe work proceduresIdentify and wear appropriate PPERespond to an arc flash

    Business & Legal Reports, Inc. 0709

    What Is an Arc Flash?Electrical short circuit or arcthrough the airConcentrated energy explodes outwardHigh-intensity flashInstantaneous arc blast pressure waveSuperheated ball of gasmelts metal, burns clothes and skinImage Credit: OSHA

    Business & Legal Reports, Inc. 0709

    Arc Flash EffectsSevere burnsFireball destroys skin and tissueHeat blast can extend several feet from sourceBurns from hot surfaces, projectiles, and fireballImage Credit: OSHAHearing lossExtensive damage to equipmentPunctures and lacerations

    Business & Legal Reports, Inc. 0709

    Causes of Arc FlashDropped toolsAccidental contact with electrical systemsImproper work proceduresInsulation failureVoltage testing with inappropriate instrumentInattentiveness

    Business & Legal Reports, Inc. 0709

    Causes of Arc Flash (cont.)Buildup of dust, impurities, and corrosion on insulating surfacesSparks produced during racking of breakers, replacement of fuses, and closing into faulted lines Birds or rodents that break leads at connections

    Business & Legal Reports, Inc. 0709

    Arc Flash Exposure RiskWorkers are at higher risk when:Exposed to energized parts often Required to perform multiple tasks Poorly trainedConcentration is broken

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    Arc Flash Exposure Risk (cont.)Risk is lower when:Clear work practices are establishedTraining is thorough and up to dateProper PPE is wornEquipment is routinely maintainedWorkers are alert

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    ExerciseHazards and RisksList 4 arc flash effectsSevere BurnsHearing LossExcessive Damage to EquipmentPuncture Wounds and Lacerations

    Business & Legal Reports, Inc. 0709

    Exercise (cont.)List at least 3 causes of arc flashDropped ToolsAccidental contact with electrical systemsImproper work proceduresInsulation failureVoltage testing with inappropriate toolBuildup of dust, impurities and corrosionSparks produced during maintenanceBirds or rodents that break connection leadsWorker Inattentiveness

    Business & Legal Reports, Inc. 0709

    Arc Flash HazardsAny Questions?Do you understand:What an arc flash is?Effects of a flash?What can cause a flash?Your exposure risk?

    Business & Legal Reports, Inc. 0709

    Arc Flash PreventionAllow only qualified personsDe-energize equipment whenever possibleCreate safe work conditionsUse proper equipment

    Business & Legal Reports, Inc. 0709

    Safe Work on Energized PartsNever work on live equipment, except when:De-energizing introduces additional or increased hazardsIt is not feasible to de-energizeThe proper training and safety equipment is provided

    Business & Legal Reports, Inc. 0709

    Safe Work Practices1. Review the operation2. Determine the hazards3. Determine and implement protective measures4. Wear appropriate PPE5. Know how to respond to an arc flash incident

    Business & Legal Reports, Inc. 0709

    Safe Work Practices Review the OperationRead all warning signsRead the hot work permitMatch the tools to the operationTake whatever readings are necessary to quantify the systems operation.

    Business & Legal Reports, Inc. 0709

    Safe Work Practices Determine the HazardsIdentify and inspect energized partsRespect the flash protection boundaryIdentify sharp objects and other obstructionsIdentify all environmental hazards

    Business & Legal Reports, Inc. 0709

    Safe Work PracticesThe Flash Protection BoundaryLimited approach boundaryRestricted approach boundaryProhibited approach boundary

    Business & Legal Reports, Inc. 0709

    Safe Work Practices Deenergizing and LockoutIdentify all possible sources of energy supplyOpen disconnecting device(s)Verify device is openApply lockout/tagout devicesTest voltagedouble check instrument ratingApply grounding devices

    Business & Legal Reports, Inc. 0709

    Safe Work Practices Wear Appropriate PPEHelmet or headgearArc-rated face shieldSafety glassesRated glovesRated shoes/bootsRated flame-resistant clothingNo metal button, clasps, or zippers!Credit: Web Soft Safety Solutions

    Business & Legal Reports, Inc. 0709

    Explosion Response ProcedureTurn off the powerExtinguish flamesCall for helpBegin CPR and first aid, if trained

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    Take Other PrecautionsOnly qualified personsWear only nonconductive apparelno jewelryWork area must be illuminatedNo conductive liquids near electrical work or equipmentDo not defeat electrical interlocksDouble-check for the right tools

    Business & Legal Reports, Inc. 0709

    Safe Work PracticesAny Questions?Do you understand about:Operations review?Hazard determination?Work practices?PPE?Emergency response?

    Business & Legal Reports, Inc. 0709

    Warning LabelsPlaced on all equipment with potential arc flash hazardPhoto Credit: MIDWEST

    Business & Legal Reports, Inc. 0709

    Reportand Dont Use Damaged EquipmentStop using and report:Broken or missing coversDamaged toolsDamaged equipmentImproper equipment placement

    Photo Credit: OSHA

    Business & Legal Reports, Inc. 0709

    Review the operation Determine the hazards Determine and implement protective measures Wear appropriate PPE Know how to respond to an arc flash incident12345What are the 5 steps to safe work practices?

    Business & Legal Reports, Inc. 0709

    Inspect equipment and work areas for arc flash hazards and risksHuman error a common cause of arc flashDe-energize whenever possibleFollow safe work practicesWear all required PPEReportand dont usedamaged equipment and tools

    Slide Show Notes Welcome to this training session about arc flash. In this session well talk about the hazards and risks of working on or near energized electrical equipment. Well also discuss the procedures for preventing an arc flash accident, and how to protect yourself from the hazards of an arc flash.Slide Show Notes By the end of the training session, you will be able to:Identify the causes and risks of arc flash;Implement procedures to prevent arc flash;Identify and wear the proper personal protective equipment, or PPE; andRespond appropriately to an arc flash incident.

    Slide Show NotesAn arc flash is a high-amperage short circuit that sends an electric current through the air. It occurs when an electric current flows between separate energized conducting surfaces, such as when circuit breakers and disconnects are opened and closed, when energized equipment is touched with a tool, or when equipment fails. Most electrical arc flash injuries do not occur in the presence of high-voltage (above 600 volts) electrical currents. Low voltage equipment sources (under 600 volts) account for most electrical arc flash occurrences. However, high-voltage incidents can be the most catastrophic.In an arc flash incident, an enormous amount of concentrated radiant energy emanates outward from the source of the arc, along with extremely hot gases (arc plasma). A high-intensity flash is produced that can be bright enough to damage your eyesight.An instantaneous and powerful pressure wave that radiates from the source of the arc flash is also produced. The wave can cover several feet in half a second.The blast can send loose material like pieces of damaged equipment, tools, molten metal, and other objects flying through the air.The thermal blast generates a superheated ball of gas that can severely burn the human body and even melt metal.Slide Show Notes Electrical burns, often severe, are a common injury from arc flash incidents.The flash itself can reach 35,000 degrees Fahrenheit, and the resultant fireball will severely burn skin and underlying tissue.The heat blast can cause severe burns several feet from the source. Severe burns can also occur from contacting surfaces or being hit by super-heated projectiles or when clothing or equipment catches fire from the thermal blast. The arc blast pressure wave can damage your hearing.Equipment that is part of or exposed to the arc blast is often severely damaged.Also, flying debris can puncture or lacerate the skin.Slide Show NotesYou can be severely injured from an arc flash without touching the energized equipment! Workers have been injured while they were several feet away from the arc flash. The causes of an arc flash include:Tools dropped on conductors, circuit breakers, or other energized parts, which can cause a short-circuit;Accidental contact with electrical systems, such as a worker accidentally touching an energized conductor thought to be de-energized;Improper work procedures, such as working on energized equipment when it should have been de-energized or locked out;Insulation failure where the fault currents magnetic effect causes conductors to separate, producing an arc; Testing electrical equipment with inappropriate instruments; andInattentiveness to the risks posed by energized equipment.Slide Show NotesHere are some additional causes of arc flash:Buildup of dust, impurities, and corrosion on insulating surfaces, which can provide a path for current;Sparks produced during racking of breakers, replacement of fuses, and closing into faulted lines; and Birds or rodents that snap leads at connections.

    Slide Show Notes The risk of an arc flash and your exposure to it depends on many factors.There is a higher risk of an arc flash incident when workers are:Exposed to energized parts repeatedly or for extend