Table Of Content

ARTICLE90—INTRODUCTION 90.2 NOTE: The following draft shows how the draft of the proposed 2012 edition of NFPA70E looks based on NFPA ARTICLE 90 staff’s reading of the Committee Actions contained in the Introduction NFPA 70E Technical Committee Report of the Technical Committees on Electrical Safety in theWorkplace (i.e., the CommitteeActionsintheReportonProposals).NFPAStaff 90.1 Purpose.Thepurposeofthisstandardistoprovidea frequentlyprepareandmakeavailabledraftssuchasthisas practical safe working area for employees relative to the an aid to participants in reviewing Technical Committee hazards arising from the use of electricity. Reports. Participants are encouraged to review this Report 90.2 Scope. onProposalsandtoraiseanyissuestheybelieveneedreso- lutionthroughthemakingofappropriatecomments.Please (A) Covered. This standard addresses electrical safety re- submit your public comments on the proposals, not on the quirements for employee workplaces that are necessary for draft.As mentioned previously, the draft is only an aid for the practical safeguarding of employees during activities reviewing the document, incorporating the proposals. suchastheinstallation,inspection,operation,maintenance, For further information on NFPA codes and standards and demolition of electric conductors, electric equipment, development rules or on how to participate in the NFPA signaling and communications conductors and equipment, codesandstandardsdevelopmentprocess,checktheNFPA and raceways for the following: [ROP-9] websiteatwww.nfpa.org,orcontactNFPACodesandStan- (1) Publicandprivatepremises,includingbuildings,struc- dards Administration at 617-770-3000, fax 617-770-3500, tures,mobilehomes,recreationalvehicles,andfloating or email [email protected] buildings (2) Yards, lots, parking lots, carnivals, and industrial sub- NFPA 70E stations Electrical Safety in the Workplace® (3) Installations of conductors and equipment that connect to the supply of electricity 2012Edition (4) Installations used by the electric utility, such as office buildings, warehouses, garages, machine shops, and IMPORTANT NOTE: This NFPA document is made recreational buildings [ROP-11] available for use subject to important notices and legal dis- claimers.Thesenoticesanddisclaimersappearinallpubli- (B) NotCovered.Thisstandarddoesnotcoverthefollow- cations containing this document and may be found under ing: the heading “Important Notices and Disclaimers Concern- (1) Installations in ships, watercraft other than floating ing NFPA Documents.” They can also be obtained on re- buildings, railway rolling stock, aircraft, or automotive questfromNFPAorviewedatwww.nfpa.org/disclaimers. vehicles other than mobile homes and recreational ve- This 2009 edition includes the following usability fea- hicles tures as aids to the user. Changes other than editorial are (2) Installations underground in mines and self-propelled highlightedwithgrayshadingwithinsectionsandwithver- mobile surface mining machinery and its attendant tical ruling for large blocks of changed or new text and for electrical trailing cable newtablesandchangedornewfigures.Whereoneormore (3) Installationsofrailwaysforgeneration,transformation, complete paragraphs have been deleted, the deletion is in- transmission, or distribution of power used exclusively dicated by a bullet ((cid:127)) between the paragraphs that remain. for operation of rolling stock or installations used ex- The index now has dictionary-style headers with helpful clusively for signaling and communications purposes identifiers at the top of every index page. Areference in brackets [ ] following a section or para- (4) Installations of communications equipment under the graph indicates material that has been extracted from an- exclusive control of communications utilities located other NFPAdocument.As an aid to the user, the complete outdoors or in building spaces used exclusively for title and edition of the source documents for extracts are such installations given inAnnexA. Extracted text may be edited for consis- tency and style and may include the revision of internal paragraph references and other references as appropriate. Requests for interpretations or revisions of extracted text shall be sent to the technical committee responsible for the source document. Information on referenced publications can be found in AnnexAandAnnex B. 2012Edition NATIONALELECTRICALCODE 70E–7 90.3 ARTICLE90—INTRODUCTION (5) Installations under the exclusive control of an electric (9) Annex F, Hazard/Risk Evaluation Procedure utility where such installations: (10) Annex G, Sample Lockout/Tagout Procedure a. Consist of service drops or service laterals, and as- (11) Annex H, Simplified, Two-Category, Arc-Rated sociated metering, or Clothing System b. Are located in legally established easements or (12) Annex I, Job Briefing and Planning Checklist rights-of-waydesignatedbyorrecognizedbypublic (13) Annex J, Energized Electrical Work Permit service commissions, utility commissions, or other (14) Annex K, General Categories of Electrical Hazards regulatory agencies having jurisdiction for such in- stallations, or (15) Annex L, Typical Application of Safeguards in the c. Are on property owned or leased by the electric Cell Line Working Zone utilityforthepurposeofcommunications,metering, (16) Annex M, Layering of Protective Clothing and Total generation, control, transformation, transmission, or SystemArc Rating distribution of electric energy. (17) AnnexN,ExampleIndustrialProceduresandPolicies for Working Near Overhead Electrical Lines and 90.3 Standard Arrangement. This standard is divided Equipment intotheintroductionandthreechapters,asshowninFigure (18) Annex O, Safety-Related Design Requirements 90.3. Chapter 1 applies generally for safety-related work practices; Chapter 3 supplements or modifies Chapter 1 90.5 Mandatory Rules, Permissive Rules, and Explana- with safety requirements for special equipment. tory Material. Chapter2appliestosafety-relatedmaintenancerequire- ments for electrical equipment and installations in work- (A) Mandatory Rules. Mandatory rules of this standard places. are those that identify actions that are specifically required Annexes are not part of the requirements of this stan- or prohibited and are characterized by the use of the terms dard but are included for informational purposes only. shall or shall not. (B) Permissive Rules. Permissive rules of this standard Applies generally to electrical Chapter 1 are those that identify actions that are allowed but not re- safety in the workplace Safety-Related quired, are normally used to describe options or alternative Work Practices methods,andarecharacterizedbytheuseofthetermsshall be permitted or shall not be required. Chapter 2 Safety related maintenance requirements Safety-Related (C) Explanatory Material. Explanatory material, such as Maintenance Requirements references to other standards, references to related sections of this standard, or information related to a Code rule, is Safety requirements for special Chapter 3 equipment; supplements and/or Safety Requirements includedinthisstandardintheformofinformationalnotes. modifies Chapter 1 for Special Equipment Such notes are informational only and are not enforceable as requirements of this standard. [ROP-13] Figure90.3 StandardArrangement. BracketscontainingsectionreferencestoanotherNFPA document are for informational purposes only and are pro- 90.4 Organization. This standard is divided into the fol- videdasaguidetoindicatethesourceoftheextractedtext. lowing three chapters and fifteen annexes: These bracketed references immediately follow the ex- (1) Chapter 1, Safety-Related Work Practices tracted text. (2) Chapter 2, Safety-Related Maintenance Requirements InformationalNote: Theformatandlanguageusedinthis (3) Chapter 3, Safety Requirements for Special Equip- standard follow guidelines established by NFPA and pub- ment lishedintheNECStyleManual.Copiesofthismanualcan beobtainedfromNFPA. (4) AnnexA, Referenced Publications (5) Annex B, Informational References 90.6 Formal Interpretations. To promote uniformity of (6) Annex C, Limits ofApproach interpretationandapplicationoftheprovisionsofthisstan- (7) Annex D, Incident Energy and Flash Protection dard, formal interpretation procedures have been estab- Boundary Calculation Methods lished and are found in the NFPA Regulations Governing (8) Annex E, Electrical Safety Program Committee Projects. 70E–8 NATIONALELECTRICALCODE 2012Edition ARTICLE100—DEFINITIONS CHAPTER1 Chapter 1 Safety-Related Work Practices the purpose of injury prevention and the determination of ARTICLE 100 safe work practices, arc flash protection boundary, and the Definitions appropriate levels of PPE. Arc Flash Suit. A complete arc-rated clothing and equip- Scope. This article contains only those definitions es- ment system that covers the entire body, except for the sential to the proper application of this standard. It is not hands and feet. [ROP-22] intended to include commonly defined general terms or InformationalNote: Anarc-flashsuitmayincludepantsor commonly defined technical terms from related codes and overalls, jacket, or a coverall and beekeeper-type hood fit- standards. In general, only those terms that are used in two tedwithafaceshield.[ROP-22] ormorearticlesaredefinedinArticle100.Otherdefinitions ArcRating.Thevalueattributedtomaterialsthatdescribes are included in the article in which they are used but may theirperformancetoexposuretoanelectricalarcdischarge. be referenced inArticle 100. The definitions in this article The arc rating is expressed in cal/cm2 and is derived from shall apply wherever the terms are used throughout this the determined value of the arc thermal performance value standard. (ATPV) or energy of breakopen threshold (E ) (should a BT material system exhibit a breakopen response below the I. General ATPVvalue).ArcratingisreportedaseitherATPVorE , BT Accessible (as applied to equipment). Admitting close whichever is the lower value. [ROP-24] approach; not guarded by locked doors, elevation, or other Informational Note No. 1: Breakopen is a material re- effective means. [70, 2008] sponseevidencedbytheformationofoneormoreholesin the innermost layer of arc-rated material that would allow Accessible (as applied to wiring methods). Capable of flametopassthroughthematerial. being removed or exposed without damaging the building structureorfinishornotpermanentlyclosedinbythestruc- Informational Note No. 2: ATPV is defined in ASTM F 1959-06 as the incident energy on a material or a multi- ture or finish of the building. [70, 2008] layer system of materials that results in a 50% probability Accessible, Readily (Readily Accessible). Capable of be- that sufficient heat transfer through the tested specimen is ing reached quickly for operation, renewal, or inspections predicted to cause the onset of a second-degree skin burn injurybasedontheStollcurve,cal/cm2.[ROP-24] without requiring those to whom ready access is requisite to climb over or remove obstacles or to resort to portable Informational Note No. 3: E is defined in ASTM F BT ladders, and so forth. [70, 2008] 1959-06 as the incident energy on a material or material system that results in a 50% probability of breakopen. Ampacity. The current, in amperes, that a conductor can Breakopen is defined as a hole with an area of 1.6 cm2 carry continuously under the conditions of use without ex- (0.5 in2) or an opening with a 2.5 cm (1.0 in.) in any ceeding its temperature rating. [70, 2008] dimension.[ROP-24] [ROP-13a] Attachment Plug (Plug Cap) (Plug). A device that, by (cid:127) Approved. Acceptable to the authority having jurisdiction. insertion in a receptacle, establishes a connection between theconductorsoftheattachedflexiblecordandtheconduc- Arc Flash Hazard. Adangerous condition associated with tors connected permanently to the receptacle. [70, 2008] the possible release of energy caused by an electric arc. Authority Having Jurisdiction (AHJ). An organization, Informational Note No. 1: An arc flash hazard may exist when energized electrical conductors or circuit parts are office, or individual responsible for enforcing the require- exposedorwhentheyarewithinequipmentinaguardedor ments of a code or standard, or approving equipment, ma- enclosed condition, provided a person is interacting with terials, an installation, or a procedure. theequipmentinsuchamannerthatcouldcauseanelectric arc.Undernormaloperatingconditions,enclosedenergized InformationalNote: Thephrase“authorityhavingjurisdic- equipment that has been properly installed and maintained tion,”oritsacronymAHJ,isusedinNFPAdocumentsina isnotlikelytoposeanarcflashhazard. broad manner, since jurisdictions and approval agencies Informational Note No. 2: See Table 130.8(C)(15)(1) for vary, as do their responsibilities. Where public safety is examplesofactivitiesthatcouldposeanarcflashhazard. primary,theauthorityhavingjurisdictionmaybeafederal, [ROP-18] state,local,orotherregionaldepartmentorindividualsuch (cid:127) as a fire chief; fire marshal; chief of a fire prevention bu- ArcFlashHazardAnalysis.Astudyinvestigatingawork- reau,labordepartment,orhealthdepartment;buildingoffi- er’s potential exposure to arc-flash energy, conducted for cial;electricalinspector;orothershavingstatutoryauthor- 2012Edition NATIONALELECTRICALCODE 70E–9 CHAPTER1 ARTICLE100—DEFINITIONS ity. For insurance purposes, an insurance inspection Branch Circuit. The circuit conductors between the final department,ratingbureau,orotherinsurancecompanyrep- overcurrent device protecting the circuit and the outlet(s). resentative may be the authority having jurisdiction. In [70, 2008] manycircumstances,thepropertyownerorhisorherdes- [ROP-36] ignated agent assumes the role of the authority having ju- (cid:127) risdiction;atgovernmentinstallations,thecommandingof- Building. Any structure used or intended for supporting or ficer or departmental official may be the authority having sheltering any use or occupancy. [101, 2009] [ROP-37] jurisdiction. Cabinet. An enclosure that is designed for either surface Automatic. Performing a function without the necessity of mounting or flush mounting and is provided with a frame, human intervention. [ROP-25] mat, or trim in which a swinging door or doors are or can Balaclava (Sock Hood). An arc-rated hood that protects be hung. [70, 2008] the neck and head except for facial area of the eyes and Circuit Breaker. A device designed to open and close a nose. [ROP-27] circuit by nonautomatic means and to open the circuit au- Bare-HandWork.Atechniqueofperformingworkonen- tomaticallyonapredeterminedovercurrentwithoutdamage ergized electrical conductors or circuit parts, after the em- to itself when properly applied within its rating. [70, 2008] ployee has been raised to the potential of the conductor or InformationalNote: Theautomaticopeningmeanscanbe circuit part. integral, direct acting with the circuit breaker, or remote fromthecircuitbreaker.[70,2008] Barricade. Aphysical obstruction such as tapes, cones, or A-frame-type wood or metal structures intended to provide Conductive. Suitable for carrying electric current. a warning about and to limit access to a hazardous area. [ROP-38, ROP-39, ROP-40] (cid:127) Barrier. Aphysical obstruction that is intended to prevent Controller. A device or group of devices that serves to contact with equipment or energized electrical conductors govern, in some predetermined manner, the electric power and circuit parts or to prevent unauthorized access to a delivered to the apparatus to which it is connected. [70, work area. 2008] [ROP-41] Bonded (Bonding). Connected to establish electrical con- (cid:127) tinuity and conductivity. [70, 2008] Current-Limiting Overcurrent Protective Device. Ade- vice that, when interrupting currents in its current-limiting Bonding Jumper. A reliable conductor to ensure the re- range,reducesthecurrentflowinginthefaultedcircuittoa quired electrical conductivity between metal parts required magnitude substantially less than that obtainable in the to be electrically connected. [70, 2008] same circuit if the device were replaced with a solid con- Boundary,ArcFlash.[ROP-30]Whenanarcflashhazard ductor having comparable impedance. exists, an approach limit at a distance from a prospective Cutout. An assembly of a fuse support with either a fuse- arc source within which a person could receive a second holder, fuse carrier, or disconnecting blade.The fuseholder degree burn if an electrical arc flash were to occur. or fuse carrier may include a conducting element (fuse Informational Note: Asecond degree burn is possible by link), or may act as the disconnecting blade by the inclu- an exposure of unprotected skin to an electric arc flash sion of a nonfusible member. above the incident-energy level of 5 J/cm2 (1.2 cal/cm2). Cutout Box. An enclosure designed for surface mounting [ROP-29] that has swinging doors or covers secured directly to and Boundary,LimitedApproach.Anapproachlimitatadis- telescoping with the walls of the box proper. [70, 2008] tance from an exposed energized electrical conductor or Deenergized. Free from any electrical connection to a circuit part within which a shock hazard exists. source of potential difference and from electrical charge; Boundary, Prohibited Approach. An approach limit at a not having a potential different from that of the earth. distance from an exposed energized electrical conductor or Device. A unit of an electrical system that carries or con- circuit part within which work is considered the same as trols electric energy as its principal function. [70, 2008] makingcontactwiththeelectricalconductororcircuitpart. Disconnecting Means. A device, or group of devices, or Boundary, Restricted Approach. An approach limit at a other means by which the conductors of a circuit can be distance from an exposed energized electrical conductor or disconnected from their source of supply. [70, 2008] circuitpartwithinwhichthereisanincreasedriskofshock, duetoelectricalarcovercombinedwithinadvertentmove- Disconnecting (or Isolating) Switch (Disconnector, ment, for personnel working in close proximity to the en- Isolator).Amechanicalswitchingdeviceusedforisolating ergized electrical conductor or circuit part. a circuit or equipment from a source of power. 70E–10 NATIONALELECTRICALCODE 2012Edition ARTICLE100—DEFINITIONS CHAPTER1 Electrical Hazard. A dangerous condition such that con- It may or may not be the complete device necessary to tact or equipment failure can result in electric shock, arc connectitintoanelectricalcircuit. flash burn, thermal burn, or blast. Ground. The earth. [70, 2008] Informational Note: Class 2 power supplies, listed low Grounded (Grounding). Connected (connecting) to voltagelightingsystems,andsimilarsourcesareexamples ground or to a conductive body that extends the ground of circuits or systems that are not considered an electrical connection. [70, 2008] hazard. Grounded,Solidly.Connectedtogroundwithoutinserting Electrical Safety. Recognizing hazards associated with the any resistor or impedance device. [70, 2008] use of electrical energy and taking precautions so that haz- ards do not cause injury or death. Grounded Conductor. A system or circuit conductor that is intentionally grounded. [70, 2008] Electrically Safe Work Condition. A state in which an electrical conductor or circuit part has been disconnected Ground Fault. An unintentional, electrically conducting from energized parts, locked/tagged in accordance with es- connectionbetweenanungroundedconductorofanelectri- tablishedstandards,testedtoensuretheabsenceofvoltage, cal circuit and the normally non–current-carrying conduc- and grounded if determined necessary. tors,metallicenclosures,metallicraceways,metallicequip- ment, or earth. Enclosed.Surroundedbyacase,housing,fence,orwall(s) that prevents persons from accidentally contacting ener- Ground-Fault Circuit-Interrupter (GFCI). A device in- gized parts. [70, 2008] [ROP-49] tended for the protection of personnel that functions to de- energize a circuit or portion thereof within an established Enclosure. The case or housing of apparatus, or the fence periodoftimewhenacurrenttogroundexceedsthevalues or walls surrounding an installation to prevent personnel established for a ClassAdevice. [70, 2008] from accidentally contacting energized parts or to protect theequipmentfromphysicaldamage.[70,2008][ROP-49] Informational Note: Class A ground-fault circuit- interrupters trip when the current to ground is 6 mA or Energized. Electrically connected to, or is, a source of higher and do not trip when the current to ground is less voltage. [70, 2008] than 4 mA. For further information, see ANSI/UL 943, Standard for Ground-Fault Circuit Interrupters. [ROP-59, Equipment. A general term, including material, fittings, ROP-60] (cid:127) devices, appliances, luminaires, apparatus, machinery, and Grounding Conductor, Equipment (EGC). The conduc- the like used as a part of, or in connection with, an electri- tive path installed to connect normally non–current- cal installation. [70, 2008] carrying metal parts of equipment together and to the sys- [ROP-50] tem grounded conductor or to the grounding electrode (cid:127) Exposed (as applied to energized electrical conductors conductor, or both. [70, 2008] or circuit parts). Capable of being inadvertently touched InformationalNoteNo.1: Itisrecognizedthattheequip- or approached nearer than a safe distance by a person. It is mentgroundingconductoralsoperformsbonding. applied to electrical conductors or circuit parts that are not InformationalNoteNo.2: SeeNFPA70,Section250.118 suitably guarded, isolated, or insulated. foralistofacceptableequipmentgroundingconductors. Exposed (as applied to wiring methods). On or attached Grounding Electrode. Aconducting object through which to the surface or behind panels designed to allow access. a direct connection to earth is established. [70, 2008] [70, 2008] Grounding Electrode Conductor. A conductor used to [ROP-53, ROP-54] connectthesystemgroundedconductorortheequipmentto (cid:127) Fitting. An accessory such as a locknut, bushing, or other a grounding electrode or to a point on the grounding elec- part of a wiring system that is intended primarily to per- trode system. [70, 2008] form a mechanical rather than an electrical function. [70, Guarded. Covered, shielded, fenced, enclosed, or other- 2008] wise protected by means of suitable covers, casings, barri- [ROP-55] ers, rails, screens, mats, or platforms to remove the likeli- (cid:127) Fuse. An overcurrent protective device with a circuit- hoodofapproachorcontactbypersonsorobjectstoapoint opening fusible part that is heated and severed by the pas- of danger. [70, 2008] sage of overcurrent through it. Incident Energy. The amount of energy impressed on a Informational Note: A fuse comprises all the parts that surface, a certain distance from the source, generated dur- formaunitcapableofperformingtheprescribedfunctions. inganelectricalarcevent.Oneoftheunitsusedtomeasure 2012Edition NATIONALELECTRICALCODE 70E–11 CHAPTER1 ARTICLE100—DEFINITIONS incident energy is calories per centimeter squared light, to position and protect the lamps and ballast (where (cal/cm2). applicable), and to connect the lamps to the power supply. It may also include parts to protect the light source or the Incident Energy Analysis. A study used to predict the ballast or to distribute the light. A lampholder is not a incident energy of an arc flash for a specified set of condi- luminaire. [70, 2008] tions. [ROP-19] Motor Control Center. An assembly of one or more en- Insulated. Separated from other conducting surfaces by a closed sections having a common power bus and princi- dielectric (including air space) offering a high resistance to pally containing motor control units. [70, 2008] the passage of current. Neutral Conductor. The conductor connected to the neu- Informational Note: When an object is said to be insu- tralpointofasystemthatisintendedtocarrycurrentunder lated, it is understood to be insulated for the conditions to normal conditions. [70, 2008] which it is normally subject. Otherwise, it is, within the [ROP-62, ROP-63] purposeoftheserules,uninsulated. (cid:127) Outlet. A point on the wiring system at which current is InterrupterSwitch.Aswitchcapableofmaking,carrying, taken to supply utilization equipment. [70, 2008] and interrupting specified currents. Overcurrent. Any current in excess of the rated current of Interrupting Rating. The highest current at rated voltage equipment or the ampacity of a conductor. It may result that a device is intended to interrupt under standard test from overload, short circuit, or ground fault. [70, 2008] conditions. [70, 2008] Informational Note: Acurrent in excess of rating may be Informational Note: Equipment intended to interrupt cur- accommodated by certain equipment and conductors for a rent at other than fault levels may have its interrupting givensetofconditions.Therefore,therulesforovercurrent rating implied in other ratings, such as horsepower or protectionarespecificforparticularsituations. lockedrotorcurrent. Overload. Operation of equipment in excess of normal, Isolated(asappliedtolocation).Notreadilyaccessibleto full-loadrating,orofaconductorinexcessofratedampac- persons unless special means for access are used. [70, ity that, when it persists for a sufficient length of time, 2008] would cause damage or dangerous overheating. A fault, Labeled. Equipment or materials to which has been at- such as a short circuit or ground fault, is not an overload. tached a label, symbol, or other identifying mark of an [70, 2008] organizationthatisacceptabletotheauthorityhavingjuris- Panelboard. A single panel or group of panel units de- diction and concerned with product evaluation, that main- signedforassemblyintheformofasinglepanel,including tains periodic inspection of production of labeled equip- buses and automatic overcurrent devices, and equipped ment or materials, and by whose labeling the manufacturer with or without switches for the control of light, heat, or indicates compliance with appropriate standards or perfor- powercircuits;designedtobeplacedinacabinetorcutout mance in a specified manner. box placed in or against a wall, partition, or other support; and accessible only from the front. [70, 2008] Listed. Equipment, materials, or services included in a list published by an organization that is acceptable to the au- Premises Wiring (System). Interior and exterior wiring, thority having jurisdiction and concerned with evaluation includingpower,lighting,control,andsignalcircuitwiring of products or services, that maintains periodic inspection together with all their associated hardware, fittings, and of production of listed equipment or materials or periodic wiringdevices,bothpermanentlyandtemporarilyinstalled. evaluation of services, and whose listing states that either This includes: (a) wiring from the service point or power the equipment, material, or services meets appropriate des- source to the outlets; or (b) wiring from and including the ignated standards or has been tested and found suitable for powersourcetotheoutletswherethereisnoservicepoint. a specified purpose. Such wiring does not include wiring internal to appli- ances, luminaires, motors, controllers, motor control cen- Informational Note: The means for identifying listed ters, and similar equipment. [70, 2008] equipment may vary for each organization concerned with productevaluation,someofwhichdonotrecognizeequip- Qualified Person. One who has skills and knowledge re- ment as listed unless it is also labeled. Use of the system lated to the construction and operation of the electrical employed by the listing organization allows the authority havingjurisdictiontoidentifyalistedproduct. equipmentandinstallationsandhasreceivedsafetytraining [ROP-61] to recognize and avoid the hazards involved. [70, 2008] (cid:127) Luminaire. A complete lighting unit consisting of a lamp Raceway. An enclosed channel of metal or nonmetallic or lamps, together with the parts designed to distribute the materials designed expressly for holding wires, cables, or 70E–12 NATIONALELECTRICALCODE 2012Edition ARTICLE100—DEFINITIONS CHAPTER1 busbars,withadditionalfunctionsaspermittedinthisstan- Structure. That which is built or constructed. [70, 2008] dard. Raceways include, but are not limited to, rigid metal Switch, Isolating. Aswitch intended for isolating an elec- conduit, rigid nonmetallic conduit, intermediate metal con- tric circuit from the source of power. It has no interrupting duit, liquidtight flexible conduit, flexible metallic tubing, rating,anditisintendedtobeoperatedonlyafterthecircuit flexible metal conduit, electrical metallic tubing, electrical has been opened by some other means. [70, 2008] nonmetallic tubing, underfloor raceways, cellular concrete floor raceways, cellular metal floor raceways, surface race- Switchboard. A large single panel, frame, or assembly of ways, wireways, and busways. [70, 2008] panels on which are mounted on the face, back, or both, switches, overcurrent and other protective devices, buses, Receptacle.Areceptacleisacontactdeviceinstalledatthe and usually instruments. Switchboards are generally acces- outlet for the connection of an attachment plug. A single sible from the rear as well as from the front and are not receptacle is a single contact device with no other contact intended to be installed in cabinets. [70, 2008] device on the same yoke. A multiple receptacle is two or more contact devices on the same yoke. [70, 2008] Switchgear, Arc-Resistant. Equipment designed to with- [ROP-65, ROP-66] stand the effects of an internal arcing fault and that directs (cid:127) the internally released energy away from the employee. Service Conductors. The conductors from the service point to the service disconnecting means. [70, 2008] Switchgear, Metal-Clad. A switchgear assembly com- pletelyenclosedonallsidesandtopwithsheetmetal,hav- Service Drop. The overhead service conductors from the ingdrawoutswitchingandinterruptingdevices,andalllive lastpoleorotheraerialsupporttoandincludingthesplices, parts enclosed within grounded metal compartments. if any, connecting to the service-entrance conductors at the Switchgear,Metal-Enclosed.Aswitchgearassemblycom- building or other structure. [70, 2008] [ROP-68, ROP-69, pletely enclosed on all sides and top with sheet metal (ex- ROP-67] (cid:127) ceptforventilatingopeningsandinspectionwindows),con- Service Lateral. The underground service conductors be- taining primary power circuit switching, interrupting tweenthestreetmain,includinganyrisersatapoleorother devices, or both, with buses and connections. This assem- structure or from transformers, and the first point of con- bly may include control and auxiliary devices. Access to nectiontotheservice-entranceconductorsinaterminalbox the interior of the enclosure is provided by doors, remov- or meter or other enclosure, inside or outside the building ablecovers,orboth.Metal-enclosedswitchgearisavailable wall.Wherethereisnoterminalbox,meter,orotherenclo- in non-arc-resistant or arc-resistant constructions. sure,thepointofconnectionisconsideredtobethepointof Switching Device. A device designed to close, open, or entrance of the service conductors into the building. [70, both, one or more electric circuits. 2008] Touch Potential. A ground potential gradient difference Service Point. The point of connection between the facili- thatcancausecurrentflowfromhandtohand,handtofoot, ties of the serving utility and the premises wiring. [70, or another path, other than foot to foot, through the body. 2008] Ungrounded. Not connected to ground or to a conductive Shock Hazard. Adangerous condition associated with the body that extends the ground connection. [70, 2008] possiblereleaseofenergycausedbycontactorapproachto energized electrical conductors or circuit parts. Unqualified Person. A person who is not a qualified per- son. Short-CircuitCurrentRating.Theprospectivesymmetri- Utilization Equipment. Equipment that utilizes electric calfaultcurrentatanominalvoltagetowhichanapparatus energyforelectronic,electromechanical,chemical,heating, or system is able to be connected without sustaining dam- lighting, or similar purposes. [70, 2008] age exceeding defined acceptance criteria. [70, 2008] Ventilated. Provided with a means to permit circulation of Single-Line Diagram. Adiagram that shows, by means of airsufficienttoremoveanexcessofheat,fumes,orvapors. single lines and graphic symbols, the course of an electric [70, 2008] circuit or system of circuits and the component devices or parts used in the circuit or system. Voltage (of a Circuit). The greatest root-mean-square (rms) (effective) difference of potential between any two Special Permission. The written consent of the authority conductors of the circuit concerned. [70, 2008] having jurisdiction. [70, 2008] Informational Note: Some systems, such as 3-phase Step Potential. Aground potential gradient difference that 4-wire,single-phase3-wire,and3-wiredirect-current,may can cause current flow from foot to foot through the body. havevariouscircuitsofvariousvoltages. 2012Edition NATIONALELECTRICALCODE 70E–13 105.1 ARTICLE110—GENERALREQUIREMENTSFORELECTRICALSAFETY-RELATEDWORKPRACTICES Voltage,Nominal.Anominalvalueassignedtoacircuitor Article130providesrequirementsforworkinvolvingelec- systemforthepurposeofconvenientlydesignatingitsvolt- trical hazards. [ROP-76] age class (e.g., 120/240 volts, 480Y/277 volts, 600 volts). Theactualvoltageatwhichacircuitoperatescanvaryfrom the nominal within a range that permits satisfactory opera- tion of equipment. [70, 2008] ARTICLE 110 General Requirements for Electrical Informational Note: See ANSI C84.1-2006, Electric PowerSystemsandEquipment—VoltageRatings(60Hz). Safety-Related Work Practices [ROP-72] (cid:127) Working On (energized electrical conductors or circuit 110.1 Relationships with Contractors (Outside Service parts).Intentionallycomingincontactwithenergizedelec- Personnel, etc.). trical conductors or circuit parts with the hands, feet, or (A) Host Employer Responsibilities. otherbodyparts,withtools,probes,orwithtestequipment, (1) The host employer shall inform contract employers of: regardless of the personal protective equipment a person is wearing. There are two categories of “working on”: Diag- a. Known hazards that are covered by this standard, nostic(testing)istakingreadingsormeasurementsofelec- thatarerelatedtothecontractemployer’swork,and tricalequipmentwithapprovedtestequipmentthatdoesnot that might not be recognized by the contract em- require making any physical change to the equipment; re- ployer or its employees pairisanyphysicalalterationofelectricalequipment(such b. Information about the employer’s installation that asmakingortighteningconnections,removingorreplacing the contract employer needs to make the assess- components, etc.). [ROP-73] ments required by Chapter 1 (2) The host employer shall report observed contract- employer-related violations of this standard to the con- tract employer. ARTICLE 105 (B) Contract Employer Responsibilities. Application of Safety-Related Work (1) The contract employer shall ensure that each of his or Practices [ROP-76] her employees is instructed in the hazards communi- cated to the contract employer by the host employer. This instruction is in addition to the basic training re- 105.1 Scope. Chapter 1 covers electrical safety-related quired by this standard. work practices and procedures for employees who are ex- (2) The contract employer shall ensure that each of his or posed to an electrical hazard in workplaces covered in the her employees follows the work practices required by scope of this standard. Electric circuits and equipment not this standard and safety-related work rules required by included in the scope of this standard might present a haz- the host employer. ard to employees working near such facilities. [ROP-76, (3) The contract employer shall advise the host employer ROP-77]. of: a. Any unique hazards presented by the contract em- 105.2 Purpose. These practices and procedures are in- ployer’s work, tended to provide for employee safety relative to specific b. Any unanticipated hazards found during the con- identified electrical hazards in the workplace. [ROP-76] tractemployer’sworkthatthehostemployerdidnot Informational Note: For general categories of electrical mention, and hazards,seeAnnexK. c. Themeasuresthecontractortooktocorrectanyvio- lations reported by the host employer under para- 105.3 Responsibility [ROP-80]. The employer shall pro- graph (A)(2) of this section and to prevent such vide the safety-related work practices and shall train the violation from recurring in the future. employee who shall then implement them. [ROP-76] (C) Documentation.Thereshallbeadocumentedmeeting 105.4 Organization. Chapter 1 of this standard is divided between the host employer and the contract employer. intofourarticles.Article100providesdefinitionsforterms [ROP-89] used in one or more of the chapters of this document.Ar- 110.2 Training Requirements. ticle 110 provides general requirements for electrical safety-related work practices.Article 120 provides require- (A) Safety Training. The training requirements contained ments for establishing an electrically safe work condition. in this section shall apply to employees who face a risk of 70E–14 NATIONALELECTRICALCODE 2012Edition ARTICLE110—GENERALREQUIREMENTSFORELECTRICALSAFETY-RELATEDWORKPRACTICES 110.2 electrical hazard that is not reduced to a safe level by the (3) The approach distances specified in Table 130.4(C)(1) applicable electrical installation requirements. Such em- and the corresponding voltages to which the qualified ployees shall be trained to understand the specific hazards person will be exposed associated with electrical energy. They shall be trained in (4) The decision-making process necessary to determine safety-related work practices and procedural requirements the degree and extent of the hazard and the personal as necessary to provide protection from the electrical haz- protective equipment and job planning necessary to ards associated with their respective job or task assign- perform the task safely ments. Employees shall be trained to identify and under- (c) An employee who is undergoing on-the-job train- stand the relationship between electrical hazards and ing for the purpose of obtaining the skills and knowledge possible injury. necessary to be considered a qualified person and who, in the course of such training, has demonstrated an ability to Informational Note: For further information concerning installation requirements, see NFPA70®, National Electri- perform specific duties safely at his or her level of training calCode®,2008edition. and who is under the direct supervision of a qualified per- son shall be considered to be a qualified person for the (B) TypeofTraining.Thetrainingrequiredbythissection performance of those specific duties. [ROP-97] [ROP-98] shall be classroom or on-the-job type, or a combination of (d) Tasks that are performed less often than once per the two. The degree of training provided shall be deter- year shall require retraining before the performance of the mined by the risk to the employee. work practices involved. (C) Emergency Procedures. Employees responsible for (e) Employeesshallbetrainedtoselectanappropriate takingactionincaseofemergencyshallbetrainedinmeth- voltage detector and shall demonstrate how to use a device ods of release of victims from contact with exposed ener- to verify the absence of voltage, including interpreting in- gizedelectricalconductorsorcircuitparts.Employeesshall dicationsprovidedbythedevice.Thetrainingshallinclude be regularly instructed in methods of first aid and emer- information that enables the employee to understand all gency procedures, such as approved methods of resuscita- limitations of each specific voltage detector that may be tion, if their duties warrant such training. Training of em- used. ployees in approved methods of resuscitation, including (f) The employer shall determine, through regular su- cardiopulmonary resuscitation and automatic external pervision and through inspections conducted on at least an defibrillator (AED) use, shall be certified by the employer annual basis that each employee is complying with the annually. [ROP-93] [ROP-92] safety-related work practices required by this standard. (D) Employee Training. [ROP-100] (1) Qualified Person. A qualified person shall be trained (2) Unqualified Persons. Unqualified persons shall be and knowledgeable of the construction and operation of trained in and be familiar with any electrical safety-related equipment or a specific work method and be trained to practices necessary for their safety. [ROP-101] recognize and avoid the electrical hazards that might be (3) Retraining. An employee shall receive additional present with respect to that equipment or work method. training (or retraining) under any of the following condi- (a) Suchpersonsshallalsobefamiliarwiththeproper tions: use of the special precautionary techniques, personal pro- (a) If the supervision or annual inspections indicate tective equipment, including arc-flash, insulating and that the employee is not complying with the safety-related shielding materials, and insulated tools and test equipment. work practices Apersoncanbeconsideredqualifiedwithrespecttocertain (b) If new technology, new types of equipment, or equipment and methods but still be unqualified for others. changes in procedures necessitate the use of safety-related (b) SuchpersonspermittedtoworkwithintheLimited work practices that are different from those that the em- Approach Boundary of exposed energized electrical con- ployee would normally use ductorsandcircuitpartsoperatingat50voltsormoreshall, (c) Ifheorshemustemploysafety-relatedworkprac- at a minimum, be additionally trained in all of the follow- tices that are not normally used during his or her regular ing: job duties (1) The skills and techniques necessary to distinguish ex- (d) Retraining shall be performed at intervals not to posed energized electrical conductors and circuit parts exceed 3 years. [ROP-104] from other parts of electrical equipment (2) The skills and techniques necessary to determine the (E) Training Documentation. The employer shall docu- nominal voltage of exposed energized electrical con- mentthateachemployeehasreceivedthetrainingrequired ductors and circuit parts by paragraph 110.2 (D).This documentation shall be made 2012Edition NATIONALELECTRICALCODE 70E–15 110.3 ARTICLE110—GENERALREQUIREMENTSFORELECTRICALSAFETY-RELATEDWORKPRACTICES when the employee demonstrates proficiency in the work ceduretobeusedbeforeworkisstartedwithintheLimited practices involved and shall be maintained for the duration Approach Boundary and before work is started within the of the employee’s employment. The documentation shall arc flash boundary of energized electrical conductors and contain the content of the training, each employee’s name, circuit parts operating at 50 volts or more or where an and dates of training. [ROP-105] electrical hazard exists. The procedure shall identify the hazard/risk process that shall be used by employees to InformationalNote: Employmentrecordsthatindicatethat evaluate tasks before work is started. [ROP-113] an employee has received the required training are an ac- ceptablemeansofmeetingthisrequirement. InformationalNoteNo.1: Thehazard/riskevaluationpro- ceduremayincludeidentifyingwhenasecondpersoncould 110.3 Electrical Safety Program. be required and the training and equipment that person shouldhave. (A) General.Theemployershallimplementanddocument Informational Note No. 2: For an example of a anoverallelectricalsafetyprogramthatdirectsactivityap- Hazard/Risk Analysis Evaluation Procedure Flow Chart, propriate for the electrical hazards, voltage, energy level, seeAnnexF. and circuit conditions. [ROP-107] Informational Note No. 3: For an example of a Hazard/RiskEvaluationProcedure,seeAnnexF. Informational Note No. 1: Safety-related work practices are just one component of an overall electrical safety (G) Job Briefing. program. (1) General. Before starting each job, the employee in InformationalNoteNo.2: ANSI/AIHAZ10-2005,Ameri- canNationalStandardforOccupationalSafetyandHealth charge shall conduct a job briefing with the employees in- Management Systems, provides a framework for establish- volved. The briefing shall cover such subjects as hazards ingacomprehensiveelectricalsafetyprogramasacompo- associated with the job, work procedures involved, special nent of an employer’s occupational safety and health precautions,energysourcecontrols,andpersonalprotective program. equipment requirements. Additional job briefings shall be (B) Awareness and Self-Discipline. The electrical safety held if changes that might affect the safety of employees program shall be designed to provide an awareness of the occur during the course of the work. [ROP-116] potential electrical hazards to employees who work in an (2) RepetitiveorSimilarTasks.Iftheworkoroperations environment with the presence of electrical hazards. The to be performed during the work day or shift are repetitive program shall be developed to provide the required self- and similar, at least one job briefing shall be conducted discipline for all employees who must perform work that before the start of the first job of the day or shift. [ROP- may involve electrical hazards. The program shall instill 116] safety principles and controls. [ROP-108] (3) Routine Work. Prior to starting work, a brief discus- (C) Electrical Safety Program Principles. The electrical sionshallbesatisfactoryiftheworkinvolvedisroutineand safetyprogramshallidentifytheprinciplesuponwhichitis if the employee is qualified for the task.Amore extensive based. discussion shall be conducted if either of the following apply: [ROP-119] Informational Note: For examples of typical electrical safetyprogramprinciples,seeAnnexE. (1) The work is complicated or particularly hazardous. (2) The employee cannot be expected to recognize and (D) Electrical Safety Program Controls. An electrical avoid the hazards involved in the job. safety program shall identify the controls by which it is measured and monitored. InformationalNote: Foranexampleofajobbriefingform andplanningchecklist,seeAnnexI. Informational Note: For examples of typical electrical safetyprogramcontrols,seeAnnexE. (H) Electrical SafetyAuditing. (E) Electrical Safety Program Procedures. An electrical (1) Electrical Safety Program . The electrical safety pro- safety program shall identify the procedures for working gramshallbeauditedtohelpensurethattheprinciplesand within the Limited Approach Boundary and for working proceduresoftheelectricalsafetyprogramarestillincom- withinthearcflashboundarybeforeworkisstarted.[ROP- pliance with the latest requirements and regulations. The 111] frequency of the audit shall not exceed three years. [ROP- InformationalNote: Foranexampleofatypicalelectrical 122] safetyprogramprocedure,seeAnnexE. (2) FieldWork.Auditingoffieldworkshallbeperformed (F) Hazard/Risk Evaluation Procedure. An electrical tohelpassurethattherequirementscontainedintheproce- safety program shall identify a hazard/risk evaluation pro- dures of the electrical safety program are being followed. 70E–16 NATIONALELECTRICALCODE 2012Edition

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NFPA 70E Technical Committee Report of the Technical. Committees on Electrical Safety in the Workplace (i.e., the. Committee Actions in the Report
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Electrical Safety in the Workplace® ARTICLE 90 Introduction PDF

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Preview Electrical Safety in the Workplace® ARTICLE 90 Introduction

ARTICLE90—INTRODUCTION 90.2 NOTE: The following draft shows how the draft of the proposed 2012 edition of NFPA70E looks based on NFPA ARTICLE 90 staff’s reading of the Committee Actions contained in the Introduction NFPA 70E Technical Committee Report of the Technical Committees on Electrical Safety in theWorkplace (i.e., the CommitteeActionsintheReportonProposals).NFPAStaff 90.1 Purpose.Thepurposeofthisstandardistoprovidea frequentlyprepareandmakeavailabledraftssuchasthisas practical safe working area for employees relative to the an aid to participants in reviewing Technical Committee hazards arising from the use of electricity. Reports. Participants are encouraged to review this Report 90.2 Scope. onProposalsandtoraiseanyissuestheybelieveneedreso- lutionthroughthemakingofappropriatecomments.Please (A) Covered. This standard addresses electrical safety re- submit your public comments on the proposals, not on the quirements for employee workplaces that are necessary for draft.As mentioned previously, the draft is only an aid for the practical safeguarding of employees during activities reviewing the document, incorporating the proposals. suchastheinstallation,inspection,operation,maintenance, For further information on NFPA codes and standards and demolition of electric conductors, electric equipment, development rules or on how to participate in the NFPA signaling and communications conductors and equipment, codesandstandardsdevelopmentprocess,checktheNFPA and raceways for the following: [ROP-9] websiteatwww.nfpa.org,orcontactNFPACodesandStan- (1) Publicandprivatepremises,includingbuildings,struc- dards Administration at 617-770-3000, fax 617-770-3500, tures,mobilehomes,recreationalvehicles,andfloating or email [email protected] buildings (2) Yards, lots, parking lots, carnivals, and industrial sub- NFPA 70E stations Electrical Safety in the Workplace® (3) Installations of conductors and equipment that connect to the supply of electricity 2012Edition (4) Installations used by the electric utility, such as office buildings, warehouses, garages, machine shops, and IMPORTANT NOTE: This NFPA document is made recreational buildings [ROP-11] available for use subject to important notices and legal dis- claimers.Thesenoticesanddisclaimersappearinallpubli- (B) NotCovered.Thisstandarddoesnotcoverthefollow- cations containing this document and may be found under ing: the heading “Important Notices and Disclaimers Concern- (1) Installations in ships, watercraft other than floating ing NFPA Documents.” They can also be obtained on re- buildings, railway rolling stock, aircraft, or automotive questfromNFPAorviewedatwww.nfpa.org/disclaimers. vehicles other than mobile homes and recreational ve- This 2009 edition includes the following usability fea- hicles tures as aids to the user. Changes other than editorial are (2) Installations underground in mines and self-propelled highlightedwithgrayshadingwithinsectionsandwithver- mobile surface mining machinery and its attendant tical ruling for large blocks of changed or new text and for electrical trailing cable newtablesandchangedornewfigures.Whereoneormore (3) Installationsofrailwaysforgeneration,transformation, complete paragraphs have been deleted, the deletion is in- transmission, or distribution of power used exclusively dicated by a bullet ((cid:127)) between the paragraphs that remain. for operation of rolling stock or installations used ex- The index now has dictionary-style headers with helpful clusively for signaling and communications purposes identifiers at the top of every index page. Areference in brackets [ ] following a section or para- (4) Installations of communications equipment under the graph indicates material that has been extracted from an- exclusive control of communications utilities located other NFPAdocument.As an aid to the user, the complete outdoors or in building spaces used exclusively for title and edition of the source documents for extracts are such installations given inAnnexA. Extracted text may be edited for consis- tency and style and may include the revision of internal paragraph references and other references as appropriate. Requests for interpretations or revisions of extracted text shall be sent to the technical committee responsible for the source document. Information on referenced publications can be found in AnnexAandAnnex B. 2012Edition NATIONALELECTRICALCODE 70E–7 90.3 ARTICLE90—INTRODUCTION (5) Installations under the exclusive control of an electric (9) Annex F, Hazard/Risk Evaluation Procedure utility where such installations: (10) Annex G, Sample Lockout/Tagout Procedure a. Consist of service drops or service laterals, and as- (11) Annex H, Simplified, Two-Category, Arc-Rated sociated metering, or Clothing System b. Are located in legally established easements or (12) Annex I, Job Briefing and Planning Checklist rights-of-waydesignatedbyorrecognizedbypublic (13) Annex J, Energized Electrical Work Permit service commissions, utility commissions, or other (14) Annex K, General Categories of Electrical Hazards regulatory agencies having jurisdiction for such in- stallations, or (15) Annex L, Typical Application of Safeguards in the c. Are on property owned or leased by the electric Cell Line Working Zone utilityforthepurposeofcommunications,metering, (16) Annex M, Layering of Protective Clothing and Total generation, control, transformation, transmission, or SystemArc Rating distribution of electric energy. (17) AnnexN,ExampleIndustrialProceduresandPolicies for Working Near Overhead Electrical Lines and 90.3 Standard Arrangement. This standard is divided Equipment intotheintroductionandthreechapters,asshowninFigure (18) Annex O, Safety-Related Design Requirements 90.3. Chapter 1 applies generally for safety-related work practices; Chapter 3 supplements or modifies Chapter 1 90.5 Mandatory Rules, Permissive Rules, and Explana- with safety requirements for special equipment. tory Material. Chapter2appliestosafety-relatedmaintenancerequire- ments for electrical equipment and installations in work- (A) Mandatory Rules. Mandatory rules of this standard places. are those that identify actions that are specifically required Annexes are not part of the requirements of this stan- or prohibited and are characterized by the use of the terms dard but are included for informational purposes only. shall or shall not. (B) Permissive Rules. Permissive rules of this standard Applies generally to electrical Chapter 1 are those that identify actions that are allowed but not re- safety in the workplace Safety-Related quired, are normally used to describe options or alternative Work Practices methods,andarecharacterizedbytheuseofthetermsshall be permitted or shall not be required. Chapter 2 Safety related maintenance requirements Safety-Related (C) Explanatory Material. Explanatory material, such as Maintenance Requirements references to other standards, references to related sections of this standard, or information related to a Code rule, is Safety requirements for special Chapter 3 equipment; supplements and/or Safety Requirements includedinthisstandardintheformofinformationalnotes. modifies Chapter 1 for Special Equipment Such notes are informational only and are not enforceable as requirements of this standard. [ROP-13] Figure90.3 StandardArrangement. BracketscontainingsectionreferencestoanotherNFPA document are for informational purposes only and are pro- 90.4 Organization. This standard is divided into the fol- videdasaguidetoindicatethesourceoftheextractedtext. lowing three chapters and fifteen annexes: These bracketed references immediately follow the ex- (1) Chapter 1, Safety-Related Work Practices tracted text. (2) Chapter 2, Safety-Related Maintenance Requirements InformationalNote: Theformatandlanguageusedinthis (3) Chapter 3, Safety Requirements for Special Equip- standard follow guidelines established by NFPA and pub- ment lishedintheNECStyleManual.Copiesofthismanualcan beobtainedfromNFPA. (4) AnnexA, Referenced Publications (5) Annex B, Informational References 90.6 Formal Interpretations. To promote uniformity of (6) Annex C, Limits ofApproach interpretationandapplicationoftheprovisionsofthisstan- (7) Annex D, Incident Energy and Flash Protection dard, formal interpretation procedures have been estab- Boundary Calculation Methods lished and are found in the NFPA Regulations Governing (8) Annex E, Electrical Safety Program Committee Projects. 70E–8 NATIONALELECTRICALCODE 2012Edition ARTICLE100—DEFINITIONS CHAPTER1 Chapter 1 Safety-Related Work Practices the purpose of injury prevention and the determination of ARTICLE 100 safe work practices, arc flash protection boundary, and the Definitions appropriate levels of PPE. Arc Flash Suit. A complete arc-rated clothing and equip- Scope. This article contains only those definitions es- ment system that covers the entire body, except for the sential to the proper application of this standard. It is not hands and feet. [ROP-22] intended to include commonly defined general terms or InformationalNote: Anarc-flashsuitmayincludepantsor commonly defined technical terms from related codes and overalls, jacket, or a coverall and beekeeper-type hood fit- standards. In general, only those terms that are used in two tedwithafaceshield.[ROP-22] ormorearticlesaredefinedinArticle100.Otherdefinitions ArcRating.Thevalueattributedtomaterialsthatdescribes are included in the article in which they are used but may theirperformancetoexposuretoanelectricalarcdischarge. be referenced inArticle 100. The definitions in this article The arc rating is expressed in cal/cm2 and is derived from shall apply wherever the terms are used throughout this the determined value of the arc thermal performance value standard. (ATPV) or energy of breakopen threshold (E ) (should a BT material system exhibit a breakopen response below the I. General ATPVvalue).ArcratingisreportedaseitherATPVorE , BT Accessible (as applied to equipment). Admitting close whichever is the lower value. [ROP-24] approach; not guarded by locked doors, elevation, or other Informational Note No. 1: Breakopen is a material re- effective means. [70, 2008] sponseevidencedbytheformationofoneormoreholesin the innermost layer of arc-rated material that would allow Accessible (as applied to wiring methods). Capable of flametopassthroughthematerial. being removed or exposed without damaging the building structureorfinishornotpermanentlyclosedinbythestruc- Informational Note No. 2: ATPV is defined in ASTM F 1959-06 as the incident energy on a material or a multi- ture or finish of the building. [70, 2008] layer system of materials that results in a 50% probability Accessible, Readily (Readily Accessible). Capable of be- that sufficient heat transfer through the tested specimen is ing reached quickly for operation, renewal, or inspections predicted to cause the onset of a second-degree skin burn injurybasedontheStollcurve,cal/cm2.[ROP-24] without requiring those to whom ready access is requisite to climb over or remove obstacles or to resort to portable Informational Note No. 3: E is defined in ASTM F BT ladders, and so forth. [70, 2008] 1959-06 as the incident energy on a material or material system that results in a 50% probability of breakopen. Ampacity. The current, in amperes, that a conductor can Breakopen is defined as a hole with an area of 1.6 cm2 carry continuously under the conditions of use without ex- (0.5 in2) or an opening with a 2.5 cm (1.0 in.) in any ceeding its temperature rating. [70, 2008] dimension.[ROP-24] [ROP-13a] Attachment Plug (Plug Cap) (Plug). A device that, by (cid:127) Approved. Acceptable to the authority having jurisdiction. insertion in a receptacle, establishes a connection between theconductorsoftheattachedflexiblecordandtheconduc- Arc Flash Hazard. Adangerous condition associated with tors connected permanently to the receptacle. [70, 2008] the possible release of energy caused by an electric arc. Authority Having Jurisdiction (AHJ). An organization, Informational Note No. 1: An arc flash hazard may exist when energized electrical conductors or circuit parts are office, or individual responsible for enforcing the require- exposedorwhentheyarewithinequipmentinaguardedor ments of a code or standard, or approving equipment, ma- enclosed condition, provided a person is interacting with terials, an installation, or a procedure. theequipmentinsuchamannerthatcouldcauseanelectric arc.Undernormaloperatingconditions,enclosedenergized InformationalNote: Thephrase“authorityhavingjurisdic- equipment that has been properly installed and maintained tion,”oritsacronymAHJ,isusedinNFPAdocumentsina isnotlikelytoposeanarcflashhazard. broad manner, since jurisdictions and approval agencies Informational Note No. 2: See Table 130.8(C)(15)(1) for vary, as do their responsibilities. Where public safety is examplesofactivitiesthatcouldposeanarcflashhazard. primary,theauthorityhavingjurisdictionmaybeafederal, [ROP-18] state,local,orotherregionaldepartmentorindividualsuch (cid:127) as a fire chief; fire marshal; chief of a fire prevention bu- ArcFlashHazardAnalysis.Astudyinvestigatingawork- reau,labordepartment,orhealthdepartment;buildingoffi- er’s potential exposure to arc-flash energy, conducted for cial;electricalinspector;orothershavingstatutoryauthor- 2012Edition NATIONALELECTRICALCODE 70E–9 CHAPTER1 ARTICLE100—DEFINITIONS ity. For insurance purposes, an insurance inspection Branch Circuit. The circuit conductors between the final department,ratingbureau,orotherinsurancecompanyrep- overcurrent device protecting the circuit and the outlet(s). resentative may be the authority having jurisdiction. In [70, 2008] manycircumstances,thepropertyownerorhisorherdes- [ROP-36] ignated agent assumes the role of the authority having ju- (cid:127) risdiction;atgovernmentinstallations,thecommandingof- Building. Any structure used or intended for supporting or ficer or departmental official may be the authority having sheltering any use or occupancy. [101, 2009] [ROP-37] jurisdiction. Cabinet. An enclosure that is designed for either surface Automatic. Performing a function without the necessity of mounting or flush mounting and is provided with a frame, human intervention. [ROP-25] mat, or trim in which a swinging door or doors are or can Balaclava (Sock Hood). An arc-rated hood that protects be hung. [70, 2008] the neck and head except for facial area of the eyes and Circuit Breaker. A device designed to open and close a nose. [ROP-27] circuit by nonautomatic means and to open the circuit au- Bare-HandWork.Atechniqueofperformingworkonen- tomaticallyonapredeterminedovercurrentwithoutdamage ergized electrical conductors or circuit parts, after the em- to itself when properly applied within its rating. [70, 2008] ployee has been raised to the potential of the conductor or InformationalNote: Theautomaticopeningmeanscanbe circuit part. integral, direct acting with the circuit breaker, or remote fromthecircuitbreaker.[70,2008] Barricade. Aphysical obstruction such as tapes, cones, or A-frame-type wood or metal structures intended to provide Conductive. Suitable for carrying electric current. a warning about and to limit access to a hazardous area. [ROP-38, ROP-39, ROP-40] (cid:127) Barrier. Aphysical obstruction that is intended to prevent Controller. A device or group of devices that serves to contact with equipment or energized electrical conductors govern, in some predetermined manner, the electric power and circuit parts or to prevent unauthorized access to a delivered to the apparatus to which it is connected. [70, work area. 2008] [ROP-41] Bonded (Bonding). Connected to establish electrical con- (cid:127) tinuity and conductivity. [70, 2008] Current-Limiting Overcurrent Protective Device. Ade- vice that, when interrupting currents in its current-limiting Bonding Jumper. A reliable conductor to ensure the re- range,reducesthecurrentflowinginthefaultedcircuittoa quired electrical conductivity between metal parts required magnitude substantially less than that obtainable in the to be electrically connected. [70, 2008] same circuit if the device were replaced with a solid con- Boundary,ArcFlash.[ROP-30]Whenanarcflashhazard ductor having comparable impedance. exists, an approach limit at a distance from a prospective Cutout. An assembly of a fuse support with either a fuse- arc source within which a person could receive a second holder, fuse carrier, or disconnecting blade.The fuseholder degree burn if an electrical arc flash were to occur. or fuse carrier may include a conducting element (fuse Informational Note: Asecond degree burn is possible by link), or may act as the disconnecting blade by the inclu- an exposure of unprotected skin to an electric arc flash sion of a nonfusible member. above the incident-energy level of 5 J/cm2 (1.2 cal/cm2). Cutout Box. An enclosure designed for surface mounting [ROP-29] that has swinging doors or covers secured directly to and Boundary,LimitedApproach.Anapproachlimitatadis- telescoping with the walls of the box proper. [70, 2008] tance from an exposed energized electrical conductor or Deenergized. Free from any electrical connection to a circuit part within which a shock hazard exists. source of potential difference and from electrical charge; Boundary, Prohibited Approach. An approach limit at a not having a potential different from that of the earth. distance from an exposed energized electrical conductor or Device. A unit of an electrical system that carries or con- circuit part within which work is considered the same as trols electric energy as its principal function. [70, 2008] makingcontactwiththeelectricalconductororcircuitpart. Disconnecting Means. A device, or group of devices, or Boundary, Restricted Approach. An approach limit at a other means by which the conductors of a circuit can be distance from an exposed energized electrical conductor or disconnected from their source of supply. [70, 2008] circuitpartwithinwhichthereisanincreasedriskofshock, duetoelectricalarcovercombinedwithinadvertentmove- Disconnecting (or Isolating) Switch (Disconnector, ment, for personnel working in close proximity to the en- Isolator).Amechanicalswitchingdeviceusedforisolating ergized electrical conductor or circuit part. a circuit or equipment from a source of power. 70E–10 NATIONALELECTRICALCODE 2012Edition ARTICLE100—DEFINITIONS CHAPTER1 Electrical Hazard. A dangerous condition such that con- It may or may not be the complete device necessary to tact or equipment failure can result in electric shock, arc connectitintoanelectricalcircuit. flash burn, thermal burn, or blast. Ground. The earth. [70, 2008] Informational Note: Class 2 power supplies, listed low Grounded (Grounding). Connected (connecting) to voltagelightingsystems,andsimilarsourcesareexamples ground or to a conductive body that extends the ground of circuits or systems that are not considered an electrical connection. [70, 2008] hazard. Grounded,Solidly.Connectedtogroundwithoutinserting Electrical Safety. Recognizing hazards associated with the any resistor or impedance device. [70, 2008] use of electrical energy and taking precautions so that haz- ards do not cause injury or death. Grounded Conductor. A system or circuit conductor that is intentionally grounded. [70, 2008] Electrically Safe Work Condition. A state in which an electrical conductor or circuit part has been disconnected Ground Fault. An unintentional, electrically conducting from energized parts, locked/tagged in accordance with es- connectionbetweenanungroundedconductorofanelectri- tablishedstandards,testedtoensuretheabsenceofvoltage, cal circuit and the normally non–current-carrying conduc- and grounded if determined necessary. tors,metallicenclosures,metallicraceways,metallicequip- ment, or earth. Enclosed.Surroundedbyacase,housing,fence,orwall(s) that prevents persons from accidentally contacting ener- Ground-Fault Circuit-Interrupter (GFCI). A device in- gized parts. [70, 2008] [ROP-49] tended for the protection of personnel that functions to de- energize a circuit or portion thereof within an established Enclosure. The case or housing of apparatus, or the fence periodoftimewhenacurrenttogroundexceedsthevalues or walls surrounding an installation to prevent personnel established for a ClassAdevice. [70, 2008] from accidentally contacting energized parts or to protect theequipmentfromphysicaldamage.[70,2008][ROP-49] Informational Note: Class A ground-fault circuit- interrupters trip when the current to ground is 6 mA or Energized. Electrically connected to, or is, a source of higher and do not trip when the current to ground is less voltage. [70, 2008] than 4 mA. For further information, see ANSI/UL 943, Standard for Ground-Fault Circuit Interrupters. [ROP-59, Equipment. A general term, including material, fittings, ROP-60] (cid:127) devices, appliances, luminaires, apparatus, machinery, and Grounding Conductor, Equipment (EGC). The conduc- the like used as a part of, or in connection with, an electri- tive path installed to connect normally non–current- cal installation. [70, 2008] carrying metal parts of equipment together and to the sys- [ROP-50] tem grounded conductor or to the grounding electrode (cid:127) Exposed (as applied to energized electrical conductors conductor, or both. [70, 2008] or circuit parts). Capable of being inadvertently touched InformationalNoteNo.1: Itisrecognizedthattheequip- or approached nearer than a safe distance by a person. It is mentgroundingconductoralsoperformsbonding. applied to electrical conductors or circuit parts that are not InformationalNoteNo.2: SeeNFPA70,Section250.118 suitably guarded, isolated, or insulated. foralistofacceptableequipmentgroundingconductors. Exposed (as applied to wiring methods). On or attached Grounding Electrode. Aconducting object through which to the surface or behind panels designed to allow access. a direct connection to earth is established. [70, 2008] [70, 2008] Grounding Electrode Conductor. A conductor used to [ROP-53, ROP-54] connectthesystemgroundedconductorortheequipmentto (cid:127) Fitting. An accessory such as a locknut, bushing, or other a grounding electrode or to a point on the grounding elec- part of a wiring system that is intended primarily to per- trode system. [70, 2008] form a mechanical rather than an electrical function. [70, Guarded. Covered, shielded, fenced, enclosed, or other- 2008] wise protected by means of suitable covers, casings, barri- [ROP-55] ers, rails, screens, mats, or platforms to remove the likeli- (cid:127) Fuse. An overcurrent protective device with a circuit- hoodofapproachorcontactbypersonsorobjectstoapoint opening fusible part that is heated and severed by the pas- of danger. [70, 2008] sage of overcurrent through it. Incident Energy. The amount of energy impressed on a Informational Note: A fuse comprises all the parts that surface, a certain distance from the source, generated dur- formaunitcapableofperformingtheprescribedfunctions. inganelectricalarcevent.Oneoftheunitsusedtomeasure 2012Edition NATIONALELECTRICALCODE 70E–11 CHAPTER1 ARTICLE100—DEFINITIONS incident energy is calories per centimeter squared light, to position and protect the lamps and ballast (where (cal/cm2). applicable), and to connect the lamps to the power supply. It may also include parts to protect the light source or the Incident Energy Analysis. A study used to predict the ballast or to distribute the light. A lampholder is not a incident energy of an arc flash for a specified set of condi- luminaire. [70, 2008] tions. [ROP-19] Motor Control Center. An assembly of one or more en- Insulated. Separated from other conducting surfaces by a closed sections having a common power bus and princi- dielectric (including air space) offering a high resistance to pally containing motor control units. [70, 2008] the passage of current. Neutral Conductor. The conductor connected to the neu- Informational Note: When an object is said to be insu- tralpointofasystemthatisintendedtocarrycurrentunder lated, it is understood to be insulated for the conditions to normal conditions. [70, 2008] which it is normally subject. Otherwise, it is, within the [ROP-62, ROP-63] purposeoftheserules,uninsulated. (cid:127) Outlet. A point on the wiring system at which current is InterrupterSwitch.Aswitchcapableofmaking,carrying, taken to supply utilization equipment. [70, 2008] and interrupting specified currents. Overcurrent. Any current in excess of the rated current of Interrupting Rating. The highest current at rated voltage equipment or the ampacity of a conductor. It may result that a device is intended to interrupt under standard test from overload, short circuit, or ground fault. [70, 2008] conditions. [70, 2008] Informational Note: Acurrent in excess of rating may be Informational Note: Equipment intended to interrupt cur- accommodated by certain equipment and conductors for a rent at other than fault levels may have its interrupting givensetofconditions.Therefore,therulesforovercurrent rating implied in other ratings, such as horsepower or protectionarespecificforparticularsituations. lockedrotorcurrent. Overload. Operation of equipment in excess of normal, Isolated(asappliedtolocation).Notreadilyaccessibleto full-loadrating,orofaconductorinexcessofratedampac- persons unless special means for access are used. [70, ity that, when it persists for a sufficient length of time, 2008] would cause damage or dangerous overheating. A fault, Labeled. Equipment or materials to which has been at- such as a short circuit or ground fault, is not an overload. tached a label, symbol, or other identifying mark of an [70, 2008] organizationthatisacceptabletotheauthorityhavingjuris- Panelboard. A single panel or group of panel units de- diction and concerned with product evaluation, that main- signedforassemblyintheformofasinglepanel,including tains periodic inspection of production of labeled equip- buses and automatic overcurrent devices, and equipped ment or materials, and by whose labeling the manufacturer with or without switches for the control of light, heat, or indicates compliance with appropriate standards or perfor- powercircuits;designedtobeplacedinacabinetorcutout mance in a specified manner. box placed in or against a wall, partition, or other support; and accessible only from the front. [70, 2008] Listed. Equipment, materials, or services included in a list published by an organization that is acceptable to the au- Premises Wiring (System). Interior and exterior wiring, thority having jurisdiction and concerned with evaluation includingpower,lighting,control,andsignalcircuitwiring of products or services, that maintains periodic inspection together with all their associated hardware, fittings, and of production of listed equipment or materials or periodic wiringdevices,bothpermanentlyandtemporarilyinstalled. evaluation of services, and whose listing states that either This includes: (a) wiring from the service point or power the equipment, material, or services meets appropriate des- source to the outlets; or (b) wiring from and including the ignated standards or has been tested and found suitable for powersourcetotheoutletswherethereisnoservicepoint. a specified purpose. Such wiring does not include wiring internal to appli- ances, luminaires, motors, controllers, motor control cen- Informational Note: The means for identifying listed ters, and similar equipment. [70, 2008] equipment may vary for each organization concerned with productevaluation,someofwhichdonotrecognizeequip- Qualified Person. One who has skills and knowledge re- ment as listed unless it is also labeled. Use of the system lated to the construction and operation of the electrical employed by the listing organization allows the authority havingjurisdictiontoidentifyalistedproduct. equipmentandinstallationsandhasreceivedsafetytraining [ROP-61] to recognize and avoid the hazards involved. [70, 2008] (cid:127) Luminaire. A complete lighting unit consisting of a lamp Raceway. An enclosed channel of metal or nonmetallic or lamps, together with the parts designed to distribute the materials designed expressly for holding wires, cables, or 70E–12 NATIONALELECTRICALCODE 2012Edition ARTICLE100—DEFINITIONS CHAPTER1 busbars,withadditionalfunctionsaspermittedinthisstan- Structure. That which is built or constructed. [70, 2008] dard. Raceways include, but are not limited to, rigid metal Switch, Isolating. Aswitch intended for isolating an elec- conduit, rigid nonmetallic conduit, intermediate metal con- tric circuit from the source of power. It has no interrupting duit, liquidtight flexible conduit, flexible metallic tubing, rating,anditisintendedtobeoperatedonlyafterthecircuit flexible metal conduit, electrical metallic tubing, electrical has been opened by some other means. [70, 2008] nonmetallic tubing, underfloor raceways, cellular concrete floor raceways, cellular metal floor raceways, surface race- Switchboard. A large single panel, frame, or assembly of ways, wireways, and busways. [70, 2008] panels on which are mounted on the face, back, or both, switches, overcurrent and other protective devices, buses, Receptacle.Areceptacleisacontactdeviceinstalledatthe and usually instruments. Switchboards are generally acces- outlet for the connection of an attachment plug. A single sible from the rear as well as from the front and are not receptacle is a single contact device with no other contact intended to be installed in cabinets. [70, 2008] device on the same yoke. A multiple receptacle is two or more contact devices on the same yoke. [70, 2008] Switchgear, Arc-Resistant. Equipment designed to with- [ROP-65, ROP-66] stand the effects of an internal arcing fault and that directs (cid:127) the internally released energy away from the employee. Service Conductors. The conductors from the service point to the service disconnecting means. [70, 2008] Switchgear, Metal-Clad. A switchgear assembly com- pletelyenclosedonallsidesandtopwithsheetmetal,hav- Service Drop. The overhead service conductors from the ingdrawoutswitchingandinterruptingdevices,andalllive lastpoleorotheraerialsupporttoandincludingthesplices, parts enclosed within grounded metal compartments. if any, connecting to the service-entrance conductors at the Switchgear,Metal-Enclosed.Aswitchgearassemblycom- building or other structure. [70, 2008] [ROP-68, ROP-69, pletely enclosed on all sides and top with sheet metal (ex- ROP-67] (cid:127) ceptforventilatingopeningsandinspectionwindows),con- Service Lateral. The underground service conductors be- taining primary power circuit switching, interrupting tweenthestreetmain,includinganyrisersatapoleorother devices, or both, with buses and connections. This assem- structure or from transformers, and the first point of con- bly may include control and auxiliary devices. Access to nectiontotheservice-entranceconductorsinaterminalbox the interior of the enclosure is provided by doors, remov- or meter or other enclosure, inside or outside the building ablecovers,orboth.Metal-enclosedswitchgearisavailable wall.Wherethereisnoterminalbox,meter,orotherenclo- in non-arc-resistant or arc-resistant constructions. sure,thepointofconnectionisconsideredtobethepointof Switching Device. A device designed to close, open, or entrance of the service conductors into the building. [70, both, one or more electric circuits. 2008] Touch Potential. A ground potential gradient difference Service Point. The point of connection between the facili- thatcancausecurrentflowfromhandtohand,handtofoot, ties of the serving utility and the premises wiring. [70, or another path, other than foot to foot, through the body. 2008] Ungrounded. Not connected to ground or to a conductive Shock Hazard. Adangerous condition associated with the body that extends the ground connection. [70, 2008] possiblereleaseofenergycausedbycontactorapproachto energized electrical conductors or circuit parts. Unqualified Person. A person who is not a qualified per- son. Short-CircuitCurrentRating.Theprospectivesymmetri- Utilization Equipment. Equipment that utilizes electric calfaultcurrentatanominalvoltagetowhichanapparatus energyforelectronic,electromechanical,chemical,heating, or system is able to be connected without sustaining dam- lighting, or similar purposes. [70, 2008] age exceeding defined acceptance criteria. [70, 2008] Ventilated. Provided with a means to permit circulation of Single-Line Diagram. Adiagram that shows, by means of airsufficienttoremoveanexcessofheat,fumes,orvapors. single lines and graphic symbols, the course of an electric [70, 2008] circuit or system of circuits and the component devices or parts used in the circuit or system. Voltage (of a Circuit). The greatest root-mean-square (rms) (effective) difference of potential between any two Special Permission. The written consent of the authority conductors of the circuit concerned. [70, 2008] having jurisdiction. [70, 2008] Informational Note: Some systems, such as 3-phase Step Potential. Aground potential gradient difference that 4-wire,single-phase3-wire,and3-wiredirect-current,may can cause current flow from foot to foot through the body. havevariouscircuitsofvariousvoltages. 2012Edition NATIONALELECTRICALCODE 70E–13 105.1 ARTICLE110—GENERALREQUIREMENTSFORELECTRICALSAFETY-RELATEDWORKPRACTICES Voltage,Nominal.Anominalvalueassignedtoacircuitor Article130providesrequirementsforworkinvolvingelec- systemforthepurposeofconvenientlydesignatingitsvolt- trical hazards. [ROP-76] age class (e.g., 120/240 volts, 480Y/277 volts, 600 volts). Theactualvoltageatwhichacircuitoperatescanvaryfrom the nominal within a range that permits satisfactory opera- tion of equipment. [70, 2008] ARTICLE 110 General Requirements for Electrical Informational Note: See ANSI C84.1-2006, Electric PowerSystemsandEquipment—VoltageRatings(60Hz). Safety-Related Work Practices [ROP-72] (cid:127) Working On (energized electrical conductors or circuit 110.1 Relationships with Contractors (Outside Service parts).Intentionallycomingincontactwithenergizedelec- Personnel, etc.). trical conductors or circuit parts with the hands, feet, or (A) Host Employer Responsibilities. otherbodyparts,withtools,probes,orwithtestequipment, (1) The host employer shall inform contract employers of: regardless of the personal protective equipment a person is wearing. There are two categories of “working on”: Diag- a. Known hazards that are covered by this standard, nostic(testing)istakingreadingsormeasurementsofelec- thatarerelatedtothecontractemployer’swork,and tricalequipmentwithapprovedtestequipmentthatdoesnot that might not be recognized by the contract em- require making any physical change to the equipment; re- ployer or its employees pairisanyphysicalalterationofelectricalequipment(such b. Information about the employer’s installation that asmakingortighteningconnections,removingorreplacing the contract employer needs to make the assess- components, etc.). [ROP-73] ments required by Chapter 1 (2) The host employer shall report observed contract- employer-related violations of this standard to the con- tract employer. ARTICLE 105 (B) Contract Employer Responsibilities. Application of Safety-Related Work (1) The contract employer shall ensure that each of his or Practices [ROP-76] her employees is instructed in the hazards communi- cated to the contract employer by the host employer. This instruction is in addition to the basic training re- 105.1 Scope. Chapter 1 covers electrical safety-related quired by this standard. work practices and procedures for employees who are ex- (2) The contract employer shall ensure that each of his or posed to an electrical hazard in workplaces covered in the her employees follows the work practices required by scope of this standard. Electric circuits and equipment not this standard and safety-related work rules required by included in the scope of this standard might present a haz- the host employer. ard to employees working near such facilities. [ROP-76, (3) The contract employer shall advise the host employer ROP-77]. of: a. Any unique hazards presented by the contract em- 105.2 Purpose. These practices and procedures are in- ployer’s work, tended to provide for employee safety relative to specific b. Any unanticipated hazards found during the con- identified electrical hazards in the workplace. [ROP-76] tractemployer’sworkthatthehostemployerdidnot Informational Note: For general categories of electrical mention, and hazards,seeAnnexK. c. Themeasuresthecontractortooktocorrectanyvio- lations reported by the host employer under para- 105.3 Responsibility [ROP-80]. The employer shall pro- graph (A)(2) of this section and to prevent such vide the safety-related work practices and shall train the violation from recurring in the future. employee who shall then implement them. [ROP-76] (C) Documentation.Thereshallbeadocumentedmeeting 105.4 Organization. Chapter 1 of this standard is divided between the host employer and the contract employer. intofourarticles.Article100providesdefinitionsforterms [ROP-89] used in one or more of the chapters of this document.Ar- 110.2 Training Requirements. ticle 110 provides general requirements for electrical safety-related work practices.Article 120 provides require- (A) Safety Training. The training requirements contained ments for establishing an electrically safe work condition. in this section shall apply to employees who face a risk of 70E–14 NATIONALELECTRICALCODE 2012Edition ARTICLE110—GENERALREQUIREMENTSFORELECTRICALSAFETY-RELATEDWORKPRACTICES 110.2 electrical hazard that is not reduced to a safe level by the (3) The approach distances specified in Table 130.4(C)(1) applicable electrical installation requirements. Such em- and the corresponding voltages to which the qualified ployees shall be trained to understand the specific hazards person will be exposed associated with electrical energy. They shall be trained in (4) The decision-making process necessary to determine safety-related work practices and procedural requirements the degree and extent of the hazard and the personal as necessary to provide protection from the electrical haz- protective equipment and job planning necessary to ards associated with their respective job or task assign- perform the task safely ments. Employees shall be trained to identify and under- (c) An employee who is undergoing on-the-job train- stand the relationship between electrical hazards and ing for the purpose of obtaining the skills and knowledge possible injury. necessary to be considered a qualified person and who, in the course of such training, has demonstrated an ability to Informational Note: For further information concerning installation requirements, see NFPA70®, National Electri- perform specific duties safely at his or her level of training calCode®,2008edition. and who is under the direct supervision of a qualified per- son shall be considered to be a qualified person for the (B) TypeofTraining.Thetrainingrequiredbythissection performance of those specific duties. [ROP-97] [ROP-98] shall be classroom or on-the-job type, or a combination of (d) Tasks that are performed less often than once per the two. The degree of training provided shall be deter- year shall require retraining before the performance of the mined by the risk to the employee. work practices involved. (C) Emergency Procedures. Employees responsible for (e) Employeesshallbetrainedtoselectanappropriate takingactionincaseofemergencyshallbetrainedinmeth- voltage detector and shall demonstrate how to use a device ods of release of victims from contact with exposed ener- to verify the absence of voltage, including interpreting in- gizedelectricalconductorsorcircuitparts.Employeesshall dicationsprovidedbythedevice.Thetrainingshallinclude be regularly instructed in methods of first aid and emer- information that enables the employee to understand all gency procedures, such as approved methods of resuscita- limitations of each specific voltage detector that may be tion, if their duties warrant such training. Training of em- used. ployees in approved methods of resuscitation, including (f) The employer shall determine, through regular su- cardiopulmonary resuscitation and automatic external pervision and through inspections conducted on at least an defibrillator (AED) use, shall be certified by the employer annual basis that each employee is complying with the annually. [ROP-93] [ROP-92] safety-related work practices required by this standard. (D) Employee Training. [ROP-100] (1) Qualified Person. A qualified person shall be trained (2) Unqualified Persons. Unqualified persons shall be and knowledgeable of the construction and operation of trained in and be familiar with any electrical safety-related equipment or a specific work method and be trained to practices necessary for their safety. [ROP-101] recognize and avoid the electrical hazards that might be (3) Retraining. An employee shall receive additional present with respect to that equipment or work method. training (or retraining) under any of the following condi- (a) Suchpersonsshallalsobefamiliarwiththeproper tions: use of the special precautionary techniques, personal pro- (a) If the supervision or annual inspections indicate tective equipment, including arc-flash, insulating and that the employee is not complying with the safety-related shielding materials, and insulated tools and test equipment. work practices Apersoncanbeconsideredqualifiedwithrespecttocertain (b) If new technology, new types of equipment, or equipment and methods but still be unqualified for others. changes in procedures necessitate the use of safety-related (b) SuchpersonspermittedtoworkwithintheLimited work practices that are different from those that the em- Approach Boundary of exposed energized electrical con- ployee would normally use ductorsandcircuitpartsoperatingat50voltsormoreshall, (c) Ifheorshemustemploysafety-relatedworkprac- at a minimum, be additionally trained in all of the follow- tices that are not normally used during his or her regular ing: job duties (1) The skills and techniques necessary to distinguish ex- (d) Retraining shall be performed at intervals not to posed energized electrical conductors and circuit parts exceed 3 years. [ROP-104] from other parts of electrical equipment (2) The skills and techniques necessary to determine the (E) Training Documentation. The employer shall docu- nominal voltage of exposed energized electrical con- mentthateachemployeehasreceivedthetrainingrequired ductors and circuit parts by paragraph 110.2 (D).This documentation shall be made 2012Edition NATIONALELECTRICALCODE 70E–15 110.3 ARTICLE110—GENERALREQUIREMENTSFORELECTRICALSAFETY-RELATEDWORKPRACTICES when the employee demonstrates proficiency in the work ceduretobeusedbeforeworkisstartedwithintheLimited practices involved and shall be maintained for the duration Approach Boundary and before work is started within the of the employee’s employment. The documentation shall arc flash boundary of energized electrical conductors and contain the content of the training, each employee’s name, circuit parts operating at 50 volts or more or where an and dates of training. [ROP-105] electrical hazard exists. The procedure shall identify the hazard/risk process that shall be used by employees to InformationalNote: Employmentrecordsthatindicatethat evaluate tasks before work is started. [ROP-113] an employee has received the required training are an ac- ceptablemeansofmeetingthisrequirement. InformationalNoteNo.1: Thehazard/riskevaluationpro- ceduremayincludeidentifyingwhenasecondpersoncould 110.3 Electrical Safety Program. be required and the training and equipment that person shouldhave. (A) General.Theemployershallimplementanddocument Informational Note No. 2: For an example of a anoverallelectricalsafetyprogramthatdirectsactivityap- Hazard/Risk Analysis Evaluation Procedure Flow Chart, propriate for the electrical hazards, voltage, energy level, seeAnnexF. and circuit conditions. [ROP-107] Informational Note No. 3: For an example of a Hazard/RiskEvaluationProcedure,seeAnnexF. Informational Note No. 1: Safety-related work practices are just one component of an overall electrical safety (G) Job Briefing. program. (1) General. Before starting each job, the employee in InformationalNoteNo.2: ANSI/AIHAZ10-2005,Ameri- canNationalStandardforOccupationalSafetyandHealth charge shall conduct a job briefing with the employees in- Management Systems, provides a framework for establish- volved. The briefing shall cover such subjects as hazards ingacomprehensiveelectricalsafetyprogramasacompo- associated with the job, work procedures involved, special nent of an employer’s occupational safety and health precautions,energysourcecontrols,andpersonalprotective program. equipment requirements. Additional job briefings shall be (B) Awareness and Self-Discipline. The electrical safety held if changes that might affect the safety of employees program shall be designed to provide an awareness of the occur during the course of the work. [ROP-116] potential electrical hazards to employees who work in an (2) RepetitiveorSimilarTasks.Iftheworkoroperations environment with the presence of electrical hazards. The to be performed during the work day or shift are repetitive program shall be developed to provide the required self- and similar, at least one job briefing shall be conducted discipline for all employees who must perform work that before the start of the first job of the day or shift. [ROP- may involve electrical hazards. The program shall instill 116] safety principles and controls. [ROP-108] (3) Routine Work. Prior to starting work, a brief discus- (C) Electrical Safety Program Principles. The electrical sionshallbesatisfactoryiftheworkinvolvedisroutineand safetyprogramshallidentifytheprinciplesuponwhichitis if the employee is qualified for the task.Amore extensive based. discussion shall be conducted if either of the following apply: [ROP-119] Informational Note: For examples of typical electrical safetyprogramprinciples,seeAnnexE. (1) The work is complicated or particularly hazardous. (2) The employee cannot be expected to recognize and (D) Electrical Safety Program Controls. An electrical avoid the hazards involved in the job. safety program shall identify the controls by which it is measured and monitored. InformationalNote: Foranexampleofajobbriefingform andplanningchecklist,seeAnnexI. Informational Note: For examples of typical electrical safetyprogramcontrols,seeAnnexE. (H) Electrical SafetyAuditing. (E) Electrical Safety Program Procedures. An electrical (1) Electrical Safety Program . The electrical safety pro- safety program shall identify the procedures for working gramshallbeauditedtohelpensurethattheprinciplesand within the Limited Approach Boundary and for working proceduresoftheelectricalsafetyprogramarestillincom- withinthearcflashboundarybeforeworkisstarted.[ROP- pliance with the latest requirements and regulations. The 111] frequency of the audit shall not exceed three years. [ROP- InformationalNote: Foranexampleofatypicalelectrical 122] safetyprogramprocedure,seeAnnexE. (2) FieldWork.Auditingoffieldworkshallbeperformed (F) Hazard/Risk Evaluation Procedure. An electrical tohelpassurethattherequirementscontainedintheproce- safety program shall identify a hazard/risk evaluation pro- dures of the electrical safety program are being followed. 70E–16 NATIONALELECTRICALCODE 2012Edition

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NFPA 70E Technical Committee Report of the Technical. Committees on Electrical Safety in the Workplace (i.e., the. Committee Actions in the Report
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