ARC Flash Boundary & NFPA

7/28/2019 ARC Flash Boundary & NFPA

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ARC Flash Boundary & NFPA-70E Requirements PPE Program1. Purpose and Scope

The Arc Flash Boundary-PPE Program was developed to minimize the risk toAMS employees from safety and health hazards in tHe work place related to thedischarge of electrical energy when working within the arc flash boundarydistance. The type of electrical equipment, Voltage of the equipment and job taskbeing performed determines this distance. The protection shall be provided bythe correct selection of PPE when employees are within the Arc Flash BoundaryDistance.This program meets the requirements establish by OSHA's Electric PowerTransmission 1910.269(1)(1 m Distribution Standards 1910.269(1)(6)(iii) andSafety Related Electrical Work Practices 1910.331, Electrical Protective Devices1910.1 37, as well as National Fire Protection Association (NFPA) standards No.70 National Electrical Code, and No. 70 E Personal and Other ProtectiveEquipment.The general requirements of th- Arc Flash Boundary (AFB) - PersonalProtection Equipment (PPE) program include access to reference tables,personal protective equipment matrix, equipment selection electricalassessment, signage, proper equipment storage and training.

2. DefinitionsArc Flash Boundary (ARC)- s the distance at which an electrical arc can flashoutward, which may endanger employees working on electrical equipment.Flash Protection Boundary (FPB) - heJcalculatedsafe working distance fromelectrical equipment which would not expose the employee to the hazardsassociated with an electrical arc flash.Electrical Assessment - an analytical evaluation which would calculate the arcflash potential of an electrical component 1hazard, used to establish the flashprotection boundary and the correct level of required PPE, determined by anelectrical engineer or the equivalent.Qualified Employees (per NFPA 70E, 2000 Edition, Standard for Electrical SafetyRequirements for Employee Workplaces) - a qualified person shall be trainedand knowledgeable of the construction and operation of equipment or a specificwork method, and be trained to recognize and avoid the electrical hazards thatmight be presentwith respect to that equipment or work method. Such personsshall also be familiar with the proper use of special precautionary techniques,personal protective equipment, insulating and shielding materia!, and insulating -- -- -- -- - -


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- ~ - . . A - . . . . -- -tools and test equipment. A persm can be considered qualified with respect tocertain equipment and methods but still be unqualified for others. Such personspermitted to work within limited approach of exposed energized conductors andcircuit parts shall at a minimum, be additionally trained in the following;

The skills and techniques necessary to distinguish exposed energizedparts from other parts of the electric equipment.The skills and techniques necessary to determine the nominal voltage ofexposed energized parts.The approach distance specified in the tables and the correspondingvoltage to which the qualified person will be exposed.Employees will be capable of reading and understanding the attachedPPE matrix, and listed approach boundaries and hazardlrisk categorytables, which are necessary to perform the task safely.

3. Working on or Near Living PartsJustification for WorkLive parts to which an employee might be exposed shall be put into anelectrically safe work condition before an employee works on or near them,unless the employer can demonstrate that deenergizing introduces additional orincreased hazards or is infeasible due to equipment design or operationallimitations. Energized parts that operate at less than 50 volts to ground shall notbe required to be deenergized if there will be no increased exposure to eiectricalburns or to explosion due to electric arcs.Energized Electrical Work PermitA. Where Required

If live parts are not placed in an electrically safe work condition (for thereasons of increased or additional hazards or infeasibility) work to beperformed shall be considered energized electrical work and shall beperformed by written permit only.

B. Elements of Work PermitThe energized electrical work permit shall include, but not limited to, thefollowing items:A description of the circuit and equipment to be worked on and their

location.a Justification for why the work must be performed in an energized

condition.A description of the safe work practices to be employed.a Results of the shock hazards analysis.

Determination of shock protection boundaries.Rssclts of the flash hazard ana!ysls.


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The Flash ~rotecG6n ou ndar yThe necessary personal protective equipment to safely perform theassigned task.Means employed to restrict the access of unqualified persons from thework area.Evidence of completion of a job briefing, including a discussion of anyjob-specific hazards.Energized work approval (authorizing or responsible management,safety officer, or owner, etc.) signature(s).

C. Exemptions to work PermitWork.performed on or near live parts by qualified persons related to taskssuch as testing, troubleshooting, voltage measuring, etc., shall be permittedto be performed without an energized electrical work permit, providedappropriate safe work practices and personal protective equipment are used.4. Approach Boundaries to Live Parts

A. Shock Hazard AnalysisA shock hazard analysis shall determine the voltage to which personnel willbe exposed, boundary requirements, and the personnel protective equipmentnecessary in order to minimize the possibility of electric shock to personnel.9. Shock Protection BoundariesThe shock protection boundaries identifiedas Limited, Restricted, andProhibited Approach Boundaries are applicable to the situation in whichapproaching personnel are exposed to live parts. See NFPA Table 130.2(C)for the distances associated with various system voltages.C. ~ p ~ r o a c ho Exposed Live Parts Operating at 50 Volts or MoreNo qualified person shall approach or take any conductive object closer toexposed live parts operating at 50 volts or more than the Restricted ApproachBoundary set forth in NFPA Table 130.2(C), unless any of the following apply:

The qualified person is insulated or guarded from the live parts operatingat 50 volts or more (insulating gloves or insulating gloves and sleeves areconsidered insulation only with regard to the energized parts upon whichwork is being perfbrmed), and no uninsula'ted part of the qualified person'sbody crosses the Prohibited Apwoach Boundary set forth in Table130.2(C).The live part operating at 50 volts or more is insulated from the qualifiedperson and from any other conductive object at a differet-it potential.The qualified person is insulated from any other conductive object asduring live-line bare-handwork.D. Approach by Unqualified Persons-


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- --..Unqualified persons shdl not be permitted to enter spaces that are acce


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- -. .. .- -H. Flash Protection BoundaryFor systems that are 600 volts or less, the Flash Protection Boundary shall be4.0 ft, based on the product of clearing times of 6 cycles (0.1 second) and theavailable bolted fault current of 50kA or any combination not exceeding 300kA cycles (5000 ampere seconds). For clearing times and bolted faultcurrents other than300 kA cycles, or under engineering supervision, the FlashProtection Boundary shall alternatively be permitted to be calculated inaccordance with the following general formula:

D, = [53 x MVA x t]"Where:

D = distance in feet from an arc source for a second-degree burnMVAbf= bolted fault capacity available at point involved (in mega volt-amps)MVA = capacity rating of transformer (mega volt-amps). For transformerswith MVA ratings below 0.75 MVA, multiply the transformer MVArating by 1.25t = time of arc exposure (in seconds)

At voltage levels above 600 volts, the Flash Protection Boundary is the distance atwhich the incident energy equals 5 ~ l c m ~( 1 . 2al/cm2), For situations where fault-clearing time is 0.1 seconds (or faster), the Flash Protection Boundary is thedistance at which the incident energy level equals 6.24 ~/cm*(1.5 al/cm2).

I. Protective Clothing and Personal Protective Equipment for Application with aFlash Hazard Analysis.Where it has been determined that work will be performed within the FlashProtection Boundary , the flash hazard analysis shall determine, the employershall document, the incident energy exposure of the worker (in calories persquare centimeter). The incident energy exposure level shall be based on theworking distance of the employee's face and chest areas from a prospectivearc source for the specific task to be performed. Flame-resistant(FR)clothing and personal protective equipment (PPE) shall be used by theemployee based on the incident energy exposure associated with the specifictask. Recognizing that incident energy increases as the distance from the arcflash decreases, additional PPE shall be used for any parts of the body that

, are closer than the distance at which the incident energy was determined asan alternative, the PPE requirementsof 130.7(C)shall be permitted to beused in lieu of the detailed flash hazard analysis approach;J. Test Instrumentsand Equipment UseOnly qualified persons shall perform testing work on or near live partsoperating at 50 volts or more.

5 . Work On or Near Uninscflated Overhead bhes


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A. Uninsulated and EnergizedWhere work is performed in locations containing uninsulated energizedoverhead lines that are not guarded or isolated, precautions shall be taken toprevent employees from contacting such lines directly with any unguardedparts of their body or indirectly through conductive materials, tools, orequipment. Where the work to be performed is such that contact withuninsulated energized overhead is possible, the lines shall be deenergizedand visibly grounded at the point of work, or suitably guarded.

B. Deenergizing or GuardingIf the lines are to be deenenergized, arrangements shall be made with theperson or organization that operates or controls the lines to deeenergize thenand visibly ground them at the point of work. If arrangements are made touse protective measures, such as guarding, isolating, or insulation, theseprecautions shall prevent each employee from contacting such lines directlywith any part of his body or indirectly through conductive materials, tools, orequipment.

C. Employer and Employee ResponsibilityAMS shall be responsible for ensuring that guards or protective measures aresatisfactory for the conditions. Employees shall comply with established workmethods and the use of protective equipment.Approach Distance for Unqualified PersonsWhen employees without electrical training are working on the ground or in aaelevated position near overtiead lines, the location shall be such that theemployee and the longest conductive object the employee might contactcannot come closer to any unguarded, energized overhead power line thanthe Limited Approach Boundary. If the voltage on the line exceeds 50 kV, thedistance shall be 3.04 m (10 ft) plus 100 mm (4 in.) for every 10 kV over 50kV.

E. Equipment GroundingIf any vehicle or mechanical equipment capable of having parts of its structureelevated near energized overhead lines is intentionally grounded, employeesworking on the ground near the point of grounding shall not stand at thegrounding location whenever there i s a possibility of overhead line contact.Additional precautions, such as the use of barricades or insulation, shall betaken to protect employees from hazardous ground potentials (step and touchpotential), which can develop within a few feet or more outward from thegrounded point.

6. Othe r Precautionsfor PersonnelActivities


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When HazardousEmployees shall be instructed to be alert at all times when they areworking near live parts operating at 50 volts or more and in worksituations where unexpected electrical hazards might exist.When ImpairedEmployees shall not knowingly be permitted to work in areascontaining live parts operating at 50 volts or more or other electricalhazards while their alertness is recognizably impaired due to illness,fatigue, or other reasons.

B. Blind ReachingEmployees shall be instructed not to reach blindly into areas that mightcontain exposed live parts where an electrical hazard exists.C. Illumination

GeneralEmployees shall not enter spaces containing live parts unlessillumination is provided that enables the employees to perform thework safely.Obstructed View of Work AreaWhere lack of illumination or an obstruction precludes observation ofthe work to performed, employees shall not perform any task near liveparts operating at 50 volts or more or where an electrical hazard exists.

D. Conductive Articles Being WornConductive articles of jewelry and clothing (such as watchbands, bracelets,rings, key chains, necklaces, metalized aprons, cloth with conductive'thread,metal headgear, or metal from glasses) shall not be worn where they presentand electrical contact hazard with exposed live parts.E. Conductive Material, Tools, and Equipment Being Handled

GeneralConductive materials, tools, and equipment that are in contact with anypart of an employee's body shall be handled in a manner that preventsaccidental contact with live parts. Such materials and equipmentinclude, but are not limited to, long conductive objects, such as ducts,pipes and tubes, conductive hose and rope, metal lined rules andscales, steel tapes, pulling lines, metal scaffold parts, structuralmembers, bull floats, and chains.Approach to Live Parts


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-. . - . .. . - . . . . ,Means shall be employed to ensure that conductive materialsapproach exposed live parts no closer than that permitted by Table130.2(C).

F. Confined or Enclosed Work SpacesWhen an employee works in a confined or enclosed space (such as amanhole or vault) that contains exposed live parts operating at 50 volts ormore or an electrical hazard exists, the employer shall provide, and theemployee shall use, protective shields, protective barriers, or insulatingmaterials as necessary to avoid inadvertent contact with these parts. Doors,hinged panels, and the like shall be secured to prevent their swinging into anemployee and causing the employee to contact exposed live parts operatingat 50 volts or more or where an electrical hazard exists.

G. Housekeeping DutiesWhere live parts present an electrical contact hazard, employees shall notperform housekeeping duties inside the Limited Approach Boundary wherethere is a possibility of contact, unless adequate safeguards (such asinsulating equipment or barriers) are provided to prevent contact. Electricallyconductive cleaning materials (including conductive solids such as steel wool,metalized cloth, and silicone carbide, as weil as conductive liquid solutions)shall not be used inside the Limited Approach Boundary unless procedures toprevent electrical contact are followed.H. Occasional Use of Flammable MaterialsWhere flammable materials.are present only occasionally, electric equipmentcapable of igniting them may not be used, unless measures are taken toprevent hazardous conditions from developing. Such materials include, butare not limited to, flammable gases, vapors, or liquids; combustible dust; andignitable fibers or flyings.. Anticipating FailureWhen there is evidence that electric equipment could fail and injure

employees, the electric equipment shall be deenergized or repaired,employees shall be protected from hazards associated with the impendingfailure of the equipment.J. Routine Opening and Closing of CircuitsLoad-rated switches, circuits breakers, or other devices specifically designedas disconnecting means shall be used for the opening, reversing, or closing ofcircuits under load conditions. Cable connectors not of the load-break type,fuses, terminal lugs, and cable splice connections shall not be permitted to beused for such purposes, except in an emergency.K. Reclosing Circuits After Protective Device Operation


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-. - .- - . - . . . .- -. . - . . - - .After a circuit is deenergized by a circuit protective device, the circuit shall notbe manually reenergized until it has been determined that the equipment andcircuit can be safely energized. The repetitive manual reclosing of circuitbreakers or reenergizing circuits through replaced fuses shall be prohibited.When it is determined from the design of the circuit and the overcurrentdevices involved that the automatic operation of a device was caused by anoverload rather than a fault condition, examination of the circuit or connectedequipment shall not be required before the circuit is reenergized.

7. Personal and Other Protective EquipmentA. GeneralEmployees working in areas where electrical hazards are present shall beprovided with, and shall use, protective equipment that is designed andconstructed for the specific part of the body to be protected and for the workto be petformed.B. Care of EquipmentProtective equipment shall be maintained is a safe, reliable condition. Theprotective equipment shall be visually inspected before each use.C. Personal Protective Equipment

1. GeneralWhen an employee is working within the Flash Protection Boundaryhelshe shall wear protective clothing and other personal protectiveequipment in accordancewith NFPA 70E.2. Movement and VisibilityWhen flame-resistant (FR) clothing is worn to protect an employee, itshall cover all ignitable clothing and shall allow for movement andvisibility.3. Head, Face, Neck, and Chin ProtectionEmployees shall wear nonconductive head protection wherever there isa danger of head injury from electric shock or burns due to contact withlive parts or from flying objects resulting from electrical explosion.Employees shall wear nonconductive protective equipment for the face,neck, and chin whenever there is a danger of injury from exposure toelectric arcs of flashes or from faying objects resulting from electricalexplosion.4. Eye ProtectionEmployees shall wear protective equipment for the eyes whenever

there is danger of injury from electric arcs, flashes, or from flying objectsresulting from electrical explosion.- - -


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5. Body ProtectionEmployees shall wear FR clothing wherever there is possible exposureto an electric arc flash above the threshold incident-energy level for asecond-degree burn. 5 J/cm2(1.2 cal/cm2). Such clothing can beprovided as shirt and trousers, or as coveralls, or as a combination ofjacket and trousers, or, for increased protection, as coveralls with jacketand trousers. Various weight fabrics are available. Generally, thehigher degree of protection is provided by heavier weight fabrics and/orby layering combinations of one or more layers of FR clothing. In somecases one or more layers of FR clothing are worn over flammable, nonmelting clothing. Non-melting, flammable, clothing, used alone, canprovide protection at low incident energy levels of 8.36 J/cm2(2.0cal/cm2)and below.

6. Hand and Arm ProtectionEmployees shall wear rubber insulating gloves where there is danger ofhand and arm injury from electric shock due to contact with live parts.Hand and arm protection shall be worn where there is possibleexposure to arc flash burn.7. Foot and Leg ProtectionWhere insulated footwear is used as protection against step and touch

potential, dielectric overshoes shall be required. Insulated soles shallnot be used as primary electrical protection.8. Selection of Personal Prdtective Equipment

When Required for Various TasksWhen selected in lieu of the flash hazard analysis, NFPD table130.7(C)(9)(a) shall be used to determine the hazardlriskcategory for a task. The assumed short-circuit current capacitiesand fault clearing times for various tasks are listed in the text andnotes to Table 130.7(C)(g)(a). for tasks not listed, or for powersystems with greater than the assumed fault clearing times, aflash hazard analysis shall be required.Both larger and smaller available short-circuit currents couldresult in higher available arc-flash energies. If the available short-circuit current increases without a decrease in the opening time ofthe overcurrent protective device, the arc-flash energy willincrease. If the available short-circuit current decreases, resultingin a longer opening time for the overcurrent protective device, arc-flash energies could also increase.


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--a Energized E f t s hat operate at less than 50 volts are not requiredto be de-energized to satisfy an "electrically safe work condition".

Consideration should be given to the capacity of the source, anyovercurrent protection between the energy source and the worker,and whether the work task related to the source operating at lessthan 50 volts increases exposure to electrical burns or toexplosion from an electric arc.

Task (Assumes Equipment is Energized, and Work is Done Within the HazardlRisk V-Rated V-RatedFlash Protection Boundary) Category Gloves ToolsPanelboards Rated 240V and Below-Notes 1 and 3Circuit breaker(CB) or fused switch operation with covers onCB or fused switch operation with covers offWork on energized parts, including voltage testingRemovelinstall CBs or fused switchesRemoval of bolted covers (to expose bare, energized parts)Opening hinged covers (to expose bare, energized parts)Panelboards or Switchboards Rated >240 V and up to 600 V (withmolded case or insulated case circuit breakers) - Note 1 and 3CB or fused switch operation with covers on 0CB of fused switch' operation with cover off 1Work on energized parts, including voltage testing 2*600 V Class Motor Control Center (MCCs)- Notes 2 (except asindicated) and 3CB or fused switch or starter operation with enclosure doors closedReading a panel meter while operating a meter switchCB or fused switch or starter operation with enclosure door openWork on control circuits with energized parts 120 V'or below, exposedWork on control circuits with energized parts > 120V, exposedlnsertion or removal of individual starter "buckets" from MCC- Note 4Application of safety grounds, after voltage testRemoval of bolted covers (to expose bare, energized parts)Opening hinged covers (to expose bare, energized parts)600 V Class Switchgear (with power ci rcuit breakers or fusedswitches)-Notes 5 and 6CB or fused switch operation with enclosure doors closedReading a panel meter while operating a meter switchCB or fused switch operation with enclosure door openWork on energized parts, including voltage testingWork on control circuits with energized parts 120 V or below, exposedWork on control circuits with energized parts 2120 V, exposedlnsertion or removal (racking) of CBs from cubicles, door openlnsertion or removal (racking) of CBs from cubicles, doors closedApplication of safety grounds, after voltage testRemoval of bolted covers (to expose bare, energized parts)Opening hinged covers (to expose bare, energized parts)


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Task (Assumes Equipment is Energized, and Work i s Done Within HazardlRisk V-Rated V-Ratedthe Flash Protection Boundary) Category Gloves ToolsOther 600V Class (277V through 600 V, nominal) Equipment - Note 3Lighting or small power transformer (600 V, maximum)Removal of bolted covers (to expose bare, energized parts) 2* N NOpening hinged covers (to expose bare, energized parts) 1 N NWork on energized parts, including voltage testing 2* Y Y?Application of safety grounds, after voltage testing 2* Y NRevenue meters (kW-hour, at primary voltage and current)Insertion or removal 2* Y NCable trough or tray cover removal or installation 1 N NMiscellaneous equipment cover removal or installation 1 N NWork on energized parts, including voltage testing 2* Y YApplication of safety grounds, after voltage test 2* Y N

NEMA E2 (fused contractor) Motor Starters, 2.3 kV through 7.2 kVContractor operationwith enclosure doors closedReadinga panel meter while operating a meter switchContractor operation with enclosure doors openWork on energized parts, including voltage testingWork on control circuits with energized parts 120 V or below, exposedWork on control circuits with energized parts >I20 V, exposedlnsertion or removal (racking) of starters from cubicles, doors openlnsertion or removal (racking) of starters from cubicles, doors closedApplication of safety grounds, after voltage testRemoval of bolted covers (to expose bare, energized parts)Opening hinged covers (to expose bare, energized parts)Metal Clad Switchgear, 1 kV and AboveCB or fused switch operation with enclosure doors closedReading a panel meter while operating a meter switch ,,CB or fused switch operation with enclosure doors openWork on energized parts, including voltage testingWork on control circuits with energized parts 120 V or below, exposedWork on control circuits with energized parts >I20 V, exposedlnsertion or removal (racking) of CBs from cubicles, doors openlnsertion or removal (racking) of CBs from cubicles, doors closedApplication of safety grounds, after voltage testRemoval of bolted covers (to expose bare, energized parts)Opening hinged covers (to expose bare, energized parts)Opening voltage transformer or control power transformer compartments

Other Equipment 1 kV and AboveMetal Clad load interrupter switches, fused or unfusedSwitch operation, doors closedWork on energized parts, including voltage testingRemoval of bolted covers (to expose bare, energized parts)Opening hinged covers (to expose bare, energized parts)Outdoor disconnect switch operation (hookstick operated)Outdoor disconnect with operation (gang-operated, from grade)lnsulated cable examination, in manhole or other confined spaceinsulated cable examination, in open area


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V-rated Gloves are gloves rated and tested for the maximum line-to-line voltage upon which work will be done.V-rated Tools are tools rated and tested for the maximum line-to-line voltage upon which work will be done.2* means that a double-layer switching hood and hearing protection are required for this task in addition to the otherHazardslRisk Category 2 requirements of Table 130.7(C)(I 0).Y = yes (required) 'N = no (not required)25 kA short circuit current available. 0.03 second (2 cycle) fault clearing time.65 kA short circuit current available. 0.03 second (2 cycle) fault clearing time.For< 10 kA short circuit currentgvailable, he hazardlrisk category required may be reduced by one number.65 kA short circuit current available, 0.33 second (20 cycle) fault clearing time.65 kA short circuit current available, up to 1.0 second (60 cycle) fault clearing time.For< 25 KA short circuit current available, the hazardlrisk category required may be reduced by one number.

9. Protective Clothing and Personal Protective Equipment MatrixOnce the HazardIRiskCategory has been identified NFPA Table130.7(C)(I0) shall be used to determine the required personalprotective equipment (PPE) for the task. Table 130.7(C)(I0) lists therequirements for protectiveclothing and other protective equipmentbased on HazardIRick Category numbersIhrough 4. This clothingand equipment shall be used when working on or near energizedequipment within the Flash Protection Boundary.See annex H for a suggestedsimplifiedapproachto ensure adequatePPEfor electricalworkers .within facilities with largeand divers electrical systems.

10. Protective Clothing CharacteristicsTable 130.7(C)(I 1) lists examples of protective clothing systems andtypical characteristics including the degree of protection for variousclothing, The protective clothing selected for the correspondinghazardlrisk category number shall have an arc rating of at least thevalue listed in the last..co!umn of Table 130.7(C)(I 1).11. Factors in Selection of Protective ClothingClothing and equipment that provide worker protection from shock andarc flash hazards shall be utilized. Clothing and equipment required for

' the degree of exposure shall be permitted to be worn alone orintegrated with flammable , nonmelting apparel. If FR clothing isrequired, it shall cover associated parts of the body as well a allflammable apparel while allowing movement and visibility. All personalprotective equipment shall be maintained is a sanitary and functionallyeffective condition. Personal protective equipment items will normally beused in conjunction with one another as a system to provide theappropriate level of protection.

LayeringNonmelting, flammable fiber garments shall be permitted to beused as under layers in conjunction with Fi3 garments in a layeredsystem for added protection. If nonmelting, flammable fibergarments ate used as underlayers the system arc rating shall besufficient to prevent breakopenai the innermost FR layer at theexpected arc exposure incident energy level to prevent ignition of- -


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- - . .~. .- ---- . . . . - .flammable underlayers. A typical layering systemmight includecotton shirt and trouser, and a FR coverall. Specific tasks mightcall for additional FR layers to achieve the required protectionlevel.Outer LayersGarments worn as outer layers over FR clothing, such as jacketsor rainwear, shall also be made from FR material.UnderlayersMeltable fibers such as acetate, nylon, polyester, polypropylene,and spandex shall not be permitted. n fabric underlayers(underwear) next to the skin.Exception: an incidental amount of elastic used on non-meltingfabric underwear or socks shall be permitted.CoverageClothing shall cover potentially exposed areas as completely aspossible. Shirt sleeves shall be fastened at the wrist, and shirtsand jackets shall be closed at the neck.FitTight-fitting clothing shall be avoided. Loose fitting clothingprovides additional thermal insulation because of sir spaces. FRapparel shall fit properly such that it does not interfere with thework task.InterferenceThe garment selected shall result in the least interference with thetask but still provide the necessary protection. The work method,location, and task could influence the protective equipmentselected.

12. Arc Flash Protective EquipmentFlash SuitsFlash suit design shall permit easy and'rapid removal by thewearer. The entire flash suit, including the hood's face shield,shall have an arc rating that is suitable for the arc flash exposure.When exterior air is supplied into the hood, the air hoses andpump housing shall be either covered by FRmateriais orconstructedof nonmelting and nonflammable materials.Face Protection


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- -. ~- ..- A -- . - . . -. -Face shields shall have an .arc rating suitable for the arc flashexposure. Face shields without an arc rating shall not be used.Eye protection (safety glasses or goggles) shall be worn underface shields or hoods.

Protective Clothing and Equipment Protective Systems for HazardlRisk CategoryHazardlRisk Category Number . - I 0 I 2 3 4(Note 3)Non-melting (according to ASTM F 1506-00) or Untreated Natural Fibera. T-shirt (short-sleeve) X X X Xb. Shirt (long-sleeve) Xc. Pants (long) X X X X X X(Note 4) (Note 6)FRClothing (Note I)a. Long-sleeve shirt X X X X(Note 9)b. Pants X X X X(Note 4) (Note 6) (Note 9)c. Coverall X(Note 5) (Note 7) (Note 9) (Note 5)d. Jacket, parka, or rainwear ANFR Protective Equipmenta. Flash suit jacket (multilayer)b. Flash suit pants (multilayer)c. Head protection1. Hard Hat

2., FR hard hat linerd. Eye Protection1. Safety glasses2. Safety gogglese.. Face and head area protection1. Arc-rated face shield, or flash suit hood2. Flash suit hood3. Hearing protection (ear canal inserts)

-X(Note 8)X(Note 8)XX XX -minimum required

f. Hand protection -Leather gloves (Note 2) ANg. Foot protectionLeather work shoes ANAN = as needed AL = select one in group AR = as requiredNotes:1. See Table 130.7(C)(I1). Arc rating for a garment is expressed in caI/cm2.2. If voltage-rated gloves are required, the leather protectors worn external to the rubber gloves satisfy this requirement.3. HazardlRisk Category Number "-1" is only defined if determined by Notes 3 or 6 of Table 130.?(C)(g)(a).4. Regular weight (minimum 12 oz/yd2fabric weight), untreated. denim cotton blue jeans are acceptable in lieu of FR pants.The FR pants used for HazardlRisk Category 1 shall have a minimum arc rating of 4.5. Alternate is to use FR coveralls (minimum are rating of 4) instead of FR shirt and FR pants.6. If the FR pants have a minimum are rating of 8, long pants of nDn-melting or untreated natural fiber are not requiredbeneath the FR pants.7. Alternate is to use FR coveralls (minimum an: rating of 4) over non-melting or untreated natural fiber pants and T-shirt.8. a face shield with a minimum are rating of 8, with wrap-around guarding to protect not only the Face, but also the forehead,ears, and neck (or, alternatively, a flash suit hood), is required.9. Alternate is tb USEh0 etsof fR coveralls (the inner with a minimumarc rating of 4 and outer coverall with a minimum are rating of 5)over non-melting or untreated natural flber clathing, instead of FR coveralls over FR shirt and FR pants over non-melting or untreated naturalf i b~ riothing.


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Typical Protective Clothing SystemsRequired MinimumHazardlRisk Clothing Description Arc Rating of PPECategory (Typical number of clothing layers is given in parentheses) [~lcrn~(callcm~)]

Non-me lting, flammable materials (i.e., untreated cotton, wool, rayon, NIAor silk, or blends of these materials) with a fabric weight at least 4.5ozlyd2 (1)FR shirt and FR pants or FR coverall (1) 16.74 (4)Cotton underwear - conventional sho rt sleeve and brieflshorts, plus 33.47 (8)FR shirt and FR pants (1 or 2)Cotton underwear plus FR shirt and F R pants plus FR coverall, or 104.6 (25)cotton underwea r plus two FR coveralls (2 or 3)Cotton underwea r plus FR shirt and FR pants plus m ultilayer flash 167.36 (40)suit (3 or more)Note: Arc rating is defined in Article 100and can be either ATPV. Or Em. ATPV is defined in ASTM F 1959-99 as the incident energy on afabric or ma terial that results in sufficient heat transfer through the fabric or material to cause the onset of a sec ond-degre e burn based on theStoll curve. EsT s defined in ASTM F 1959-99as the avera ge of the five highest incident energy exposu re valves below the Stroll curve wherethe specimen s do not exhibit breakopen. EMs reported when ATPV cannot be measured due to FR fabric breakopen.

13. Hand ProtectionLeather or FR gloves shall be worn where required for arc flashprotection. Where insulating rubber gloves are used for shockprotection, leather protectors shall be worn over the rubber gloves.

14. Foot ProtectionHeavy-duty leather work shoes provide some arc flash protection tothe feet and shall be used in all tasks in HazardiRisk Category2 andhigher.

D. Clothing Material CharacteristicsFR clothing shall meet the requirements described in NFPA 70E.1. Melting

Clothing made from flammable synthetic materials that melt attemperatures below 315C (600F), such as acetate, nylon, polyester,polypropylene, and spandex, wither alone or in blends, shall not beused.

2. FlammabilityClothing made from nanmelting flammable natural materials, such ascotton, wool, rayon, or silk, shall be permitted for HazardiRiskCategories 0 and -1 considered acceptable if it is determined by flashhazard analysis that the exposure level is 8.36 ~ l c m ~2.0 calicm2) orless, and that the fabric will not ignite and continue to burn under thearc exposure hazard conditions to which itwill be exposed.

3. Care and Maintenance of FR Clothing and FR Flash Suits


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- ---- - . - .- - -InspectionFR apparel shall be inspected before each use. Work clothing orflash suits that are contaminated, or damaged to the extent theirprotectivequalities are impaired, shall not be used. Protectiveitems that become contaminated with grease, oil, or flammableliquids or combustible materials shall not be used.Manufacturer's InstructionsThe garment manufacturer's instruction for care and maintenanceof FR apparel shall be followed.

E. Other Protective Equipmentlnsulated Tools and EquipmentEmployees shall use insulated tools and/or handling equipment whenworking inside the Limited Approach Boundary of exposed live parts wheretools or handling equipment might make accidental contact. lnsulated toolsshall be protected from damage to the insulating material.

1 . Requirements for insulatedToolsThe following requirementsshall apply to insulatedtools:

lnsulated tools shall be rated for the voltages on which they areused.lnsulated tools shall be designed and constructed for theenvironment to which they are exposed and the manner in whichthey are used.

2. Fuse or Fuse Holding EquipmentFuse of fuse holder handling equipment, insulated for the circuitvoltage, shall be used to remove or install a fuse if the fuse terminalsare energized.

3. Ropes and HandlinesRopes and handlines used near exposed live parts operating at 50volts or more, or used where an electrical hazard exists, shall benonconductive.

4. ~iber~lass-~einforcedlastic Rods.Fiberglass-reinforced plastic rod and tube used for live line tools shallmeet the requirements of ASTM F 7.11.

5. Portable LaddersPortable ladders shall have nonconductive side rails if they are usedwhere the employee or ladder could contact exposed live partsoperating at 50 v o k or more or where an electrical hazard exists.

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-- - -~onconduct ive~ddershall meet the requirements of ANSIstandards for ladder.6. Protective ShieldsProtective shields, protective barriers, or insulating materials shall beused to protect each employee from shock, burns, or otherelectrically related injuries while that employee is working near liveparts that might be accidentally contacted or where dangerouselectric heating or arcing might occur. When normally enclosed liveparts are exposed for maintenance or repair, they shall be guarded toprotect unqualified persons from contact with.the live parts.7. Rubber Insulating EquipmentRubber insulating equipment used for protection from accidentalcontact with live parts shall meet the requirements of the ASTMstandards.8. Voltage Rated Plastic Guard EquipmentPlastic guard equipment for protection of employees from accidentalcontact with live parts, or for protection of employees or energizedequipment or material from contact with ground, shall meet therequirements ~f the ASTM standards.

F. Alerting Techniques1. Safety Signs and TagsSafety signs, safety s)iinbols, or accident prevention tags shall beused where necessary to warn employees about electrical hazardsthat might endanger them. Such signs and tags shall meet therequirements of ANSI Standard 2535.2. BarricadesBarricades shall be used in conjunction with safety signs where it is

necessary to prevent or limit employee access to work areascontaining live parts. Conductive barricades shall not be used whereit might cause an electrical hazard. Barricades shall be placed nocloser that the Limited Approach Boundary.

Documents

ARC Flash Boundary & NFPA