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8/12/2019 Subcontractor Elec

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Subcontractor Electrical Safety & NFPA 70E

Electrical Safety for Subcontractors andSubcontract Technical Representatives

EFCOG Electrical Safety Task Group

Module 8


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EFCOG Electrical Safety Task Group 2

Objective

To provide understanding of electrical safetyrequirements for the Subcontract TechnicalRepresentative and the Subcontractor

To facilitate communications of requirements to thesubcontractorTo serve as an aid in assessing a subcontractorsperformance


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Why is NFPA 70E a subcontractor requirement? DOE Order 440.1A, Worker Protection Management For DOE And Contractor

Employees Requires Implementation OSHA General Duty Clause requires workplace free from recognized hazards.

OSHA has cited General Duty Clause for failure to comply with 70E 10CFR 851 requires compliance with NFPA 70E NFPA 70E, Section 110.4 Multiemployer Relationship

(A) Safe Work Practices. On multiemployer worksites (in all industrysectors), more than one employer may be responsible for hazardousconditions that violate safe work practices.

(B) Outside Personnel (Contractors, etc.) the on-site employer and theoutside employer(s) shall inform each other of existing hazards, personalprotective equipment/clothing requirements, safe work practiceprocedures applicable to the work to be performed.

NFPA 70E, Standard for Electrical Safety in the Workplace


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Can OSHA Cite NFPA 70E?

OSHA regulations are often described as the Shall and NFPA70E as the How for electrical safety in the workplace.

OSHA commonly cites the General Duty Clause and uses NFPA

70E as evidence of compliance

From an OSHA Letter of Interpretation dated July 23, 2003:Industry consensus standards, such as NFPA 70E, can be usedby employers as guides to making the assessments andequipment selections required by the standard. Similarly, inOSHA enforcement actions, they can be used as evidence ofwhether the employer acted reasonably.


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How does NFPA 70E differ from the National ElectricCode (NEC)?

NFPA 70E is intended to provide work practices to minimize

the worker from electrical energy when using or working onor near electrical equipment and conductors The NEC is intended to provide a safe electrical installation

so that equipment is safe when operating normally


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What work practices does NFPA 70E require? Chapter 1, Safety-Related Work Practices

Article 100, Definitions

Article 110, General Requirements for electrical Safety-RelatedWork Practices

Article 120, Establishing an Electrically Safe Work Condition

Article 130, Working On or Near Live Parts


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NFPA 70E Training Requirements

Employees shall be trained to understand specifichazards associated with electrical energy

Trained in safety related work practices and proceduralrequirements for specific job or task

Trained to understand relationship between electricalhazards and possible injury

Training shall be classroom or on-the-job type orcombination

Employees working on or near energized conductors shallbe trained in release of victims from contact


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NFPA 70E Qualified Person

A qualified person shall be trained and knowledgeable ofconstruction and operation of equipment or workmethod and trained to recognize and avoid hazard(110.6(D)(1))

Familiar with precautionary techniques, personal protectiveequipment including arc flash, insulating and shieldingmaterials, insulated tools and test equipment

Distinguish exposed energized parts from other parts

Determine nominal voltage of live parts Understand safe approach distances in Table 130.2C Determine personal protective equipment for task


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NFPA 70E Job Briefing

Before starting each job, employee in charge shallconduct a job briefing with employees involved.(110.7G)

Identify hazards Identify procedures to be followed Special precautions Energy source controls Personal protective equipment


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Electrical Safe Work Condition

Live parts to which an employee might be exposed shallbe put into an electrically safe work condition before anemployee works on of near them unless the employeecan demonstrate work on energized components canbe justified (110.8A)

Deenergizing introduces additional or increased hazards(Examples include interruption of life support equipment,deactivation of emergency alarm systems, shutdown of

hazardous location ventilation equipment) Deenergizing is infeasible due to equipment design oroperational limitations. (Examples include start-up ortroubleshooting diagnostics and testing)


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Achieving an Electrically Safe Work Condition

An Electrically Safe Condition shall be achieved by completing allthe followingDetermine all sources of electrical supply (Drawings, diagrams)Open disconnecting device for each source

Visually verify all blades of disconnecting devices are fully openor drawout-type breakers are withdrawnApply lockout/tagout devices in accordance with policyTest each phase conductor using adequately rated voltage

detectorGround phase conductors where possibility exists for inducedor stored energy


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Achieving an Electrically Safe Work Condition

Electrical conductors and circuit parts that have beendisconnected but not under lockout/tagout, tested andgrounded (where appropriate) shall not be considered

to be in an electrically safe work condition Safe work practices shall be used in this case identical toworking on or near exposed live parts

Applies regardless of whether equipment is temporary,

permanent or portable


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Energized Electrical Work

If live parts are not placed in an electrically safe workcondition, work shall be considered energizedelectrical work

A written Energized Electrical Work Permit shall be requiredwhere live parts are not placed in an electrically safe workcondition.

Exemption: work such as testing, troubleshooting, voltagemeasurement shall be permitted to be performed without anenergized electrical work permit provided appropriate safework practices and PPE are provided and used.


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Elements of Energized Electrical Work Permit

Permit shall include the following items Description of circuit and equipment to be worked Justification for performing work in energized condition

Description of safe work practices Results of shock hazard and flash hazard analysis Shock protection boundary Personal protective equipment Means to restrict access to unqualified persons Evidence of job briefing Work approval signatures


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Working on or Near Exposed ElectricalConductors or Circuit Parts

Perform electrical hazard analysis if live parts (50 volts ormore) can not be placed in an electrically safe workcondition

Shock Hazard Analysis (Determine limited, restrictedand prohibited approach boundaries and shock PPE)Flash Hazard Analysis (Determine arc flash boundaryand PPE for personnel within this boundary)Use Energized Electrical Work Permit


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Shock and Arc Boundaries


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Limits of Approach Limited ApproachBoundary

Energizedpanel

(


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m s o pproac es r c e pproacBoundary

Energizedpart

Prohibited Restricted The closest distance toexposed live parts aqualified person canapproach w/out properPPE and tools.

To cross this boundary,the qualified personmust wear PPE andhave proper tools.

12 inches for480 volts


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Limits of Approach - Shock

Energizedpart

Prohibited

Crossed ONLY by a qualifiedperson, which when crossed bybody part or object, requires thesame protection as if directcontact was made with the live

part.1 inch for

480 volts


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Approach Boundaries for Shock Protection


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Limits of Approach Flash ProtectionBoundary

Energizedpart

Prohibited Restricted Limited

The distance from exposedlive parts within which aperson could receive asecond degree burn if anarc flash were to occur.

Arc flash PPE is requiredwithin this boundary.

Note:Distance may beless than or greater thanthe shock protectionboundaries.

Calculated distance

FlashProtectionBoundary


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Flash Hazard Analysis

An arc flash hazard analysis shall be done to protectpersonnel from injury by arc flash exposureThis analysis determines the flash protection boundaryand potential thermal exposure to personnel workingon or near exposure live parts within the boundaryPersonal protective clothing and protective equipmentfor workers inside the flash protection boundary arethen selected to mitigate potential thermal exposureEquipment may be labeled with the results of the arcflash hazard analysis and shock protection analysis


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Typical Equipment Label


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Examples of PPE

Hazard RiskCategory 1



Hazard RiskCategory 4Hazard Risk

Category 0


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EFCOG Electrical Safety Task Group27

Alternative to Flash Hazard Analysis

The PPE requirements of NFPA 70E, 130.7(C)(9)(a) shallbe permitted in lieu of the detailed flash hazardanalysis

Use Table 130.7(C)(9)(a) to determine hazard/risk categoryfor task Ensure the short circuit capacities and fault clearing time for

task listed in the text and notes are not exceeded

Use Table 130.7(C)(10) to determine the PPE for the task


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Table 130.7(C)(9)(A)


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Table 130.7(C)(10)


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Example Using Alternative Method

Work task involves testing for absence of voltage inside a480 volt MCC cubicle to establish a lockout point.

What is the Hazard/Risk Category?

What notes apply to the task? Are V-rated glove and tools required? What PPE is required for the Qualified Worker?


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AnswerRefer to 600 V Class Motor Control Centers section in Table130.7(C)(9)(A) and choose task for work on energized parts,including voltage testing. Hazard/Risk Category is 2*

Notes 2 and 3 apply to this task. Confirm with Engineering thatshort circuit current of 65kA and 0.03 fault clearing time notexceeded. If short circuit current < 10 kA, hazard/risk categorycan be reduced by one number

V-rated gloves and tools are required


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Using Table 130.7(C)(10), identify PPE requirement listedunder Category 2

T-shirt

Long sleeve FR shirt and pants or coveralls Hard hat Safety glasses or safety goggles Flash suit hood and hearing protection (2* footnote to Table

130.7(C)(9)(A) requires hood for this task) Leather gloves over voltage rated gloves Leather work shoes


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Personal Protective Equipment Care

Clothing shall be inspected prior to use by user. Clothing or flash suits that are damaged shall not be used. Clothing that become contaminated with grease, oil or flammable liquids

or combustible materials shall not be used.

V-rated gloves shall be inspected prior to use by user. Shall betested and certified every 6 months.


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Inspecting Voltage Rated Gloves in Field

Visual Inspection

Inflation

Reverse glove and repeat

Store in appropriate glove bag


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Precautions Working on or Near Live Parts

Dont reach blindly into areas that might containexposed live partsProvide illumination in spaces to enable safe work

Conductive articles of jewelry and clothing such aswatchbands, bracelets, necklaces shall not be wornUse only insulated tools rated for voltage whenworking inside the Limited Approach Boundary ofexposed live parts where contact might be made
http://www.aplussafety.net/products/store.cfm?d=3053&c=4194&p=15992&do=detail


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Typical Voltage Rated Insulated Tools
http://www.aplussafety.net/products/store.cfm?d=3053&c=4194&p=15992&do=detail


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Alerting and Barricades

How to protect the shock and arc flash approachboundaries from an unqualified person?

Barrier tape Orange cones Signage Plastic chain Use an attendant to warn others approaching the area


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NFPA 70E Compliance for Subcontractors

Summary NFPA 70E is more than just Arc Flash requirements Elements provided, but entire standard may be applicable

Chapter 1 provides Safety-Related Work Practices Subcontractor responsible for own personnel safety Communication both ways is imperative

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