Subcontractor Electrical Safety & NFPA 70E Electrical Safety for Subcontractors and Subcontract Technical Representatives EFCOG Electrical Safety Task.

Subcontractor Electrical Safety & NFPA 70E

Electrical Safety for Subcontractors and Subcontract Technical Representatives

EFCOG Electrical Safety Task Group

Module 8

NFPA 70EStandard forElectrical SafetyRequirements forEmployee Workplaces2004 Edition

EFCOG Electrical Safety Task Group 2

Objective

To provide understanding of electrical safety requirements for the Subcontract Technical Representative and the Subcontractor

To facilitate communications of requirements to the subcontractor

To serve as an aid in assessing a subcontractors performance


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 industry sectors), more than one employer may be responsible for hazardous conditions that violate safe work practices.

• (B) Outside Personnel (Contractors, etc.)… the on-site employer and the outside employer(s) shall inform each other of existing hazards, personal protective equipment/clothing requirements, safe work practice procedures… applicable to the work to be performed.

NFPA 70E, Standard for Electrical Safety in the Workplace


Can OSHA Cite NFPA 70E?

OSHA regulations are often described as the “Shall” and NFPA 70E 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 used by employers as guides to making the assessments and equipment selections required by the standard. Similarly, in OSHA enforcement actions, they can be used as evidence of whether the employer acted reasonably.”



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

– NFPA 70E is intended to provide work practices to minimize the worker from electrical energy when using or working on or near electrical equipment and conductors

– The NEC is intended to provide a safe electrical installation so that equipment is safe when operating normally



What work practices does NFPA 70E require?

– Chapter 1, Safety-Related Work Practices

• Article 100, Definitions

• Article 110, General Requirements for electrical Safety-Related Work Practices

• Article 120, Establishing an Electrically Safe Work Condition

• Article 130, Working On or Near Live Parts


NFPA 70E Training Requirements

Employees shall be trained to understand specific hazards associated with electrical energy– Trained in safety related work practices and procedural

requirements for specific job or task– Trained to understand relationship between electrical

hazards and possible injury– Training shall be classroom or on-the-job type or

combination– Employees working on or near energized conductors shall be

trained in release of victims from contact


NFPA 70E Qualified Person

A qualified person shall be trained and knowledgeable of construction and operation of equipment or work method and trained to recognize and avoid hazard (110.6(D)(1))– Familiar with precautionary techniques, personal protective

equipment including arc flash, insulating and shielding materials, 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


NFPA 70E Job Briefing

Before starting each job, employee in charge shall conduct a job briefing with employees involved. (110.7G)– Identify hazards– Identify procedures to be followed– Special precautions– Energy source controls– Personal protective equipment


Electrical Safe Work Condition

Live parts to which an employee might be exposed shall be put into an electrically safe work condition before an employee works on of near them unless the employee can demonstrate work on energized components can be 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 or operational limitations. (Examples include start-up or troubleshooting diagnostics and testing)


Electrically Safe Work Condition

Infeasible– adj : not capable of being carried out or put into practice

Inconvenient– adj : not suited to your comfort, purpose or needs

“Financial considerations are not an adequate reason to work on or near energized circuits” (Std. 1584-2002 IEEE)


Achieving an Electrically Safe Work Condition

An Electrically Safe Condition shall be achieved by completing all the following

Determine all sources of electrical supply (Drawings, diagrams) Open disconnecting device for each source Visually verify all blades of disconnecting devices are fully open

or drawout-type breakers are withdrawn Apply lockout/tagout devices in accordance with policy Test each phase conductor using adequately rated voltage

detector Ground phase conductors where possibility exists for induced

or stored energy


Achieving an Electrically Safe Work Condition

Electrical conductors and circuit parts that have been disconnected but not under lockout/tagout, tested and grounded (where appropriate) shall not be considered to be in an electrically safe work condition– Safe work practices shall be used in this case identical to

working on or near exposed live parts– Applies regardless of whether equipment is temporary,

permanent or portable


Energized Electrical Work

If live parts are not placed in an electrically safe work condition, work shall be considered energized electrical work– A written Energized Electrical Work Permit shall be required

where live parts are not placed in an electrically safe work condition.

– Exemption: work such as testing, troubleshooting, voltage measurement shall be permitted to be performed without an energized electrical work permit provided appropriate safe work practices and PPE are provided and used.


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


Working on or Near Exposed Electrical Conductors or Circuit Parts

Perform electrical hazard analysis if live parts (50 volts or more) can not be placed in an electrically safe work condition

Shock Hazard Analysis (Determine limited, restricted and prohibited approach boundaries and shock PPE)

Flash Hazard Analysis (Determine arc flash boundary and PPE for personnel within this boundary)

Use Energized Electrical Work Permit


Shock and Arc Boundaries


Limits of Approach – Limited Approach Boundary

Energized panel

(<750V)

Prohibited Restricted Limited

3 feet 6 inches for 480V

The closest distance an “unqualified” person can approach, unless escorted by a “qualified” person.


Limits of Approach – Restricted Approach Boundary

Energized part

Prohibited Restricted The closest distance to exposed live parts a “qualified” person can approach w/out proper PPE and tools.

To cross this boundary, the qualified person must wear PPE and have proper tools.

12 inches for 480 volts


Limits of Approach - Shock

Energized part

Prohibited

Crossed ONLY by a “qualified” person, which when crossed by body part or object, requires the same protection as if direct contact was made with the live part.

1 inch for 480 volts


Approach Boundaries for Shock Protection


Limits of Approach – Flash Protection Boundary

Energized part

Prohibited Restricted Limited

•The distance from exposed live parts within which a person could receive a second degree burn if an arc flash were to occur.

•Arc flash PPE is required within this boundary.

•Note: Distance may be less than or greater than the shock protection boundaries.

Calculated distance

Flash Protection Boundary


Flash Hazard Analysis

An arc flash hazard analysis shall be done to protect personnel from injury by arc flash exposure

This analysis determines the flash protection boundary and potential thermal exposure to personnel working on or near exposure live parts within the boundary

Personal protective clothing and protective equipment for workers inside the flash protection boundary are then selected to mitigate potential thermal exposure

Equipment may be labeled with the results of the arc flash hazard analysis and shock protection analysis


Typical Equipment Label


Personal Protective Clothing


Examples of PPE

Hazard Risk Category 1



Hazard Risk Category 4Hazard Risk

Category 0


Alternative to Flash Hazard Analysis

The PPE requirements of NFPA 70E, 130.7(C)(9)(a) shall be permitted in lieu of the detailed flash hazard analysis– Use Table 130.7(C)(9)(a) to determine hazard/risk category

for 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


Table 130.7(C)(9)(A)


Table 130.7(C)(10)


Example Using Alternative Method

Work task involves testing for absence of voltage inside a 480 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?



Answer Refer to “600 V Class Motor Control Centers” section in Table

130.7(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 that short circuit current of 65kA and 0.03 fault clearing time not exceeded. If short circuit current < 10 kA, hazard/risk category can be reduced by one number

V-rated gloves and tools are required



Using Table 130.7(C)(10), identify PPE requirement listed under 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


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 be tested and certified every 6 months.


Inspecting Voltage Rated Gloves in Field

•Visual Inspection

•Inflation

•Reverse glove and repeat

•Store in appropriate glove bag


Precautions Working on or Near Live Parts

Don’t reach blindly into areas that might contain exposed live parts

Provide illumination in spaces to enable safe work Conductive articles of jewelry and clothing such as

watchbands, bracelets, necklaces shall not be worn Use only insulated tools rated for voltage when

working inside the Limited Approach Boundary of exposed live parts where contact might be made


Typical Voltage Rated Insulated Tools


Alerting and Barricades

How to protect the shock and arc flash approach boundaries from an unqualified person?– Barrier tape– Orange cones– Signage– Plastic chain– Use an attendant to warn others approaching the area


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

Subcontractor Electrical Safety & NFPA 70E Electrical Safety for Subcontractors and Subcontract Technical Representatives EFCOG Electrical Safety Task.

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