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1、NFPA 70E Standard for Electrical Safety in the WorkplaceDan LazorcakWill RogersObjectivesNFPA 70E Overview and BackgroundNFPA 70E vs- OSHA complianceNFPA 70E Safety Related Work Practices & DefinitionsImplementation 3 Step ProcessLabeling and PermitsCase StudyWhat is NFPA 70E?A document that address
2、es electrical safety standards for employees who install, maintain or repair electrical systems2004 Edition has an introduction, 4 Chapters and 13 AnnexesChapter 1 Safety-Related Work Practices is the core of 70EChapters 2-4:2 - Safety-Related Maintenance Requirements3 - Safety Requirements for Spec
3、ial Equipment4 - Installation Safety RequirementsAnnexes A M: Lots of good information and examplesNFPA 70E A little backgroundFirst published in 1979 as a joint effort between NFPA and OSHA1995 Edition (5th edition) included many of the current workplace safety requirements2000 Edition (6th edition
4、) added requirements for Flash Protection Boundaries & Flame Retardant Clothing2004 Edition (7th edition) emphasizes Safe Work PracticesNFPA 70E A little backgroundOSHA bases its electrical safety mandates, found in 1910 and 1926 on the information found in NFPA 70ENFPA 70E is recognized as the tool
5、 that illustrates how an employer might comply with OSHA standards re: electrical safe work practicesRelationship can be described as:OSHA is the “SHALL”NFPA 70E is the “HOW”Is Compliance with 70E Mandatory?Simple answer: NO!70E is a national consensus safety standard published by the NFPA to assist
6、 OSHA in preparing electrical safety standardsBUTOSHA has proposed to use the 2000 edition of 70E as the basis for future revisions to its electrical safety-related work practices (4/5/04 Federal Register)Can I be cited for failing to comply with the requirements of NFPA 70E?.YES!.In the event of an
7、 electrical shock or arc flash burn incident, history has shown OSHA will cite under:1910.335, which requires the use of PPE when working where a potential electrical hazard exists1910.132, which requires the employer to assess the workplace for hazards and the need for PPEGeneral Duty ClauseIs Comp
8、liance with 70E Mandatory?Bottom line.The employer is expected to use consensus standards to help achieve compliance with OSHA regulationsIn a 2003 Standards Interpretation letter, OSHA stated that 70E can be used as evidence of whether or not an employer acted reasonablyNFPA 70E Details & Definitio
9、nsDefinitionsFlash Hazard: A dangerous condition associated with the release of energy caused by an electric arcCan result in temperatures up to 35,000 degrees F4 times hotter than the surface of the sunCan produce fatal burns up to 5ft. from the arc and severe burns up to 10ft. awayDefinitionsArc-B
10、last: Results from the rapid heating of air and the vaporization of metalCreates a pressure wave that can damage hearingCauses a concussion resulting in memory lossCan result in flying metal, some of which may be molten and/or toxicDefinitionsFlash Hazard Analysis: A study investigating a workers po
11、tential exposure to arc-flash energy.Conducted for:Determination of Injury PreventionDetermination of Safe Work PracticesAppropriate levels of PPEDefinitionsFlash Protection Boundary: An approach limit (distance from exposed live parts) which a person could receive a second degree burn if an electri
12、cal arc flash were to occurIncident Energy: Amount of energy impressed on a surface, a certain distance from the source, generated during an electrical arc event (cal/cm2) Chapter 1: Safety-Related Work PracticesTraining requirements for Qualified and Unqualified personsRequires an Electrical Safety
13、 Program and specifies its contentStresses the need to work on equipment that is de-energized via Lockout/TagoutOSHA only allows work on live electrical parts under 2 special circumstances:When continuity of service is requiredWhen de-energizing equipment would create additional hazardsChapter 1: Sa
14、fety-Related Work PracticesElectrical Hazards Analysis for Shock and FlashApproach Boundaries for ShockArc-Flash BoundariesSelection of PPE for Working on Energized Electrical EquipmentEnergized Electrical Work PermitsNFPA 70E - ImplementationThree Step Process1.Conduct both a shock and flash hazard
15、 analysis to determine incident energy potential within the Flash Protection Boundary2.Determine PPE clothing needs based upon the incident energy level associated with the task3.Select PPE matching the hazard to the arc rating of the garment/equipmentStep 1: Conduct a Hazards Analysis - Shock Hazar
16、d AnalysisDetermines the voltage to which personnel will be exposed, boundary requirements and PPE necessary to minimize electrical shockApproach boundaries specified in Table 130.2(C)Step 1: Conduct a Hazards Analysis Flash Hazard AnalysisDetermine the Flash Protection Boundary (FPB) based upon cal
17、culations found in Section 130.3(A)Determine the necessary Protective Clothing and PPE to be used for work performed within the FPBBased upon the incident energy exposure of the workerStep 1: Conduct a Hazards Analysis Flash Hazard AnalysisPPE for use inside the FPB can be determined two ways:Method
18、 A: Estimates the incident energy level by determining hazard risk category classifications from tables of common work tasks (Table 130.7(C)(9)Method B: Estimates the incident energy level based on knowledge of the electrical system and work practices (Annex D)Note: Annex H Lays out a suggested simp
19、lified two category FR clothing system that provides 2 PPE clothing categoriesYou could memorize 100s of equations, use 200+ variables, and pages and pages of calculations.it seems complex, but several freeware Excel templates make it a little easier.Heres a couple of examplesAnd more . . .Lets do o
20、ne real quick. But first well need to define a couple of variables.Definitions: (with the freeware, you only need to know a few things to get started)DistanceSeems obvious, but the standard is 18”Arc DurationFrom fuse manufacturer (.0084 sec) orBreaker manufacturer (.25 sec)Definitions (continued)Im
21、pedance (%Z) at transformerUsually labeled on transformerBolted FaultThis is where TRW needed help. We used the MVA method with our EE.The available amps - NOT a bolted faultMVA method was best for TRWThink of a large pipe filled with waterOK, lets do a live example“Nutshell” versionGet the bolted f
22、ault for major systemsDetermine your time (breaker or fuse)Decide your approach distance (18”?)Plug it in get cal/cm2Determine PPEApply labelingWhy do we do it?.It seems like a lot of troubleIt takes too longIt costs moneyIts not exactly stimulatingIt not actually the law (yet)Youll get a LOT of res
23、istanceso, WHY?Just a moment (.0084 seconds to be exact)Step 2: Determine PPE based on Hazards AnalysisThere are 5 Hazard/Risk Categories with 0 being the least hazardous and 4 being the most hazardousThe Hazard/Risk Category is determined by the incident exposure level you calculated in Step 1Compa
24、re the Hazard/Risk Category with Table 130.7(C)(11) to determine Protective Clothing needsStep 3: Select Protective ClothingGarments are based upon their ability to protect against electric arcsStandard requires that garments have a minimum Arc Rating (maximum incident energy resistance)General remi
25、nderClothing made from meltable fibers (such as acetate, nylon, polyester, etc) are not permitted in fabric underlayers (underwear) next to the skinStep 3: Select Protective ClothingFlame Retardant Clothing Pants/Shirts/Cover-allsVoltage Rated Gloves w/ Leather ProtectorsHearing ProtectionHardhatArc
26、-Rated FaceshieldLeather Work ShoesFlash SuitsSafety GlassesPPE Label ExamplePPE LEVEL 3Caution: Arc Flash and Shock HazardMinimum PPE Required: FR pants,FR long sleeve shirt, hard hat,safety glasses, arc-rated faceshield,hearing protection, voltage-ratedgloves with leather protectors,leather work s
27、hoes NFPA 70ELabeling 2002 NEC 110.6Requires all switchboards, panel boards, industrial control panels and motor control centers to be field marked.Equipment installed after 2002 needs to be labeled.Equipment installed prior to 2002, must be labeled if ANY modifications or upgrades take place.Energi
28、zed Electrical Work PermitRequired when working on live electrical equipment 50VPermits shall include the requirements of Article 130(A)(2)Example in Annex JExemptions for qualified persons performing troubleshooting, testing, voltage measuring, etcCase StudyCase Study: Ford Motor Co.Electrical inci
29、dent in Buffalo NY Stamping Plant Sept. 1999Electrical apprentice sustained serious burn injuries while attempting to sever cables feeding through a junction boxEmployee cut into a live 460V cableCase Study: Investigation foundEmployee did not lockout all energy sources or perform voltage check prio
30、r to cuttingFord provides FR coveralls; doesnt require them to be worn under 600VFord doesnt require insulated gloves, faceshields or non-conductive headwear under 440VEmployee wearing safety glasses, non-conductive footwear and non-FR coverallsEmployee was not wearing insulated gloves, faceshields
31、or non-conductive headwear Case Study CitationsFord violated 1910.335(a)(1)(i) by not requiring employees to wear FR clothing and insulated glovesFord violated 1910.335(a)(1)(v) by not providing or requiring electricians to wear appropriate face protection. Full faceshields should have been used.Fin
32、ed $14,000 Case Study OutcomeFord agreed to develop, document and implement hazard analysis evaluating plant specific tasks that create the potential for exposure to electrical hazards performed by one or more of Fords 4,000 electriciansAgreement covers all 37 manufacturing and distribution centers
33、in the US.Agreed to use NFPA 70E to develop the Hazard AnalysisIn Closing, Ask Yourself:Are my employees adequately protected when dealing with energized electrical components?If yes, what means have you used to determine adequacy?Do my employees have the necessary PPE available?If yes, do they know why, when and where to use it?If the answer to either of these questions is NO, you may want to look into NFPA 70E
