NETA Handbook Series II - Safety Vol 2-PDF

VOLUME 2 SAFETY HANDBOOK

VOLUME 2

SERIES II

ANDBOOK

Published By

IRISS Sponsored by Published by NETA - The InterNational Electrical Testing Association

AFETY

SERIES II

SAFETY HANDBOOK VOLUME II

Published by

InterNational Electrical Testing Association

Published by InterNational Electrical Testing Association 3050 Old Centre Avenue, Suite 102, Portage, Michigan 49024 269.488.6382 www.netaworld.org

NOTICE AND DISCLAIMER NETA Technical Papers and Articles are published by the InterNational Electrical Testing Association. Opinions, views, and conclusions expressed in articles herein are those of the authors and not necessarily those of NETA. Publication herein does not constitute or imply any endorsement of any opinion, product, or service by NETA, its directors, officers, members, employees, or agents (hereinafter “NETA”). All technical data in this publication reflects the experience of individuals using specific tools, products equipment, and components under specific conditions and circumstances which may or may not be fully reported and over which NETA has neither exercised nor reserved control. Such data has not been independently tested or otherwise verified by NETA. NETA makes no endorsement, representation, or warranty as to any opinion, product, or service referenced in this publication. NETA expressly disclaims any and all liability to any consumer, purchaser, or any other person using any product or service referenced herein for any injuries or damages of any kind whatsoever, including, but not limited to, any consequential, special incidental, direct, or indirect damages. NETA further disclaims any and all warranties, express or implied including, but not limited to, any implied warranty or merchantability or any implied warranty of fitness for a particular purpose. Please Note: All biographies of authors and presenters contained herein are reflective of the professional standing of these individuals at the time the articles were originally published. Titles, companies, and other factors may have changed since the original publication date. Copyright © 2013 by InterNational Electrical Testing Association, all rights reserved. No part of this publication may be reproduced in any form or by any means, electronic or mechanical, without permission in writing from the publisher.

SAFETY HANDBOOK VOLUME II

TABLE OF CONTENTS Communication is a Key Element to Electrical Safety in the Workplace.................................................................................................5 NETA Safety Committee

Lockout/Tagout: Taking It For Granted............................................................................8 Jim White and Ron Widup, Shermco Industries

Medium- Voltage Starter Control Circuit: Safety Issue.....................................................11 Al Havens, E-Hazard.com

PPE Requirements for Installation of Temporary Protective Grounds......................................................................................13 Scott Blizard and Paul Chamberlain, American Electrical Testing Co. Inc.

The Forgotten Workplace, Home..................................................................................16 Don Brown, Sharmco Industries

Using Personal Protective Grounds in Industrial Facilities............................................20 Lynn Hamrick, Shermco Industries

When Is an Energized Electrical: Work Permit Required?............................................22 Lynn Hamrick, Shermco Industries

Electrical Emergency Repsonse: Methods Of Release.....................................................25 Dave Smith, Canada Training Group

Changes to 29 CFR 1926 Subpart CC: Cranes and Derricks - Working Around Overhead Power Lines..................................................28 James R. White, Shermco Industries

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InterNational Electrical Testing Association 3050 Old Centre Avenue, Suite 102, Portage, Michigan 49024

269.488.6382

www.netaworld.org

SAFETY HANDBOOK VOLUME II

TABLE OF CONTENTS CONTINUED... Utilizing Only Qualified Persons for Electrical Work Can Reduce Risk...................... 33 Dennis K. Neitzel, C.P.E., AVO Training Institute Inc.

Wearing PPE: Important or Not?............................................................................ 39 Jim White and Ron Widup, Shermco Industries

Implementing Lightning Protection Systems ......................................................... 42 Lynn Hamrick and Owen Wyatt

Lubrication: The Do’s and Don’ts of Electrical Equipment Lubrication ...................... 45 Paul Chamberlain, American Electrical Testing Co.

ASTM F18 Report Electrical Protective Equipment 4/16/2012 to 4/17/2012............................................................................. 47 Ralph Patterson,Power Products Solutions

Arc-Flash Clothing and PPE - What Does NFPA 70E Say?..................................... 50 Jim White and Ron Widup, Shermco Industries

Battery Safety Concerns................................................................................... 53 Stephen Canale, American Electrical Testing Co.

Performing Personal Audits............................................................................... 58 Ralph Patterson,Power Products Solutions

NETA Accredited Companies............................................................................ 61

Published by

InterNational Electrical Testing Association 3050 Old Centre Avenue, Suite 102, Portage, Michigan 49024

269.488.6382

www.netaworld.org

Safety Handbook

5

COMMUNICATION IS A KEY ELEMENT TO ELECTRICAL SAFETY IN THE WORKPLACE NETA World, Winter 2011-2012 Issue By NETA Safety Committee For industrial facilities, OSHA requirements, as well as the NFPA 70E standard, are provided to delineate the work rules and personal protective equipment necessary to identify and mitigate the effects of electrical hazards in the workplace. The purpose of this Safety Corner article is to place emphasis on how these requirements rely on effective communication to enhance electrical safety in the workplace. The NFPA 70E standard will be used as the basis for this article. Effective communication typically considers both content and context. Content is what is being communicated either in a written or verbal form. With respect to electrical safety in the workplace, the standards and associated written procedures are the content of effective electrical safety communication. Context has to do with understanding the language and circumstances of the communication. Worker training, skills, and knowledge of electrical equipment and electrical hazards are the context of effective electrical safety communication. A qualified worker is capable of taking requirements and procedural content and putting it in the appropriate context to perform an electrical work task safely.

so that the electrical hazards are mitigated. Further clarification is provided that, if equipment is not locked or tagged out in accordance with this process, it should be considered energized. • Electrically Hazardous Work Conditions – NFPA 70E, Article 130, provides a description of the circumstances that would allow electrically hazardous work to be performed. To ensure proper electrical hazard awareness, requirements associated with performing shock hazard and arc-flash hazard analyses are provided. Based on these analyses, the qualified electrical worker can select the appropriate work practices and personal protective equipment associated with performing the work safely. Additionally, requirements for equipment labeling and electrical hazard alerting techniques (i.e., safety signs and tags, barricades, attendants, etc.) are presented. NFPA 70E is a living document that is updated every three to four years. Therefore, its content should be reviewed with each issued revision. There is no grandfathering associated with implementing electrical safety requirements in the workplace. New or updated safety requirements must be implemented upon issuance.

ELECTRICAL SAFETY COMMUNICATION CONTENT

ELECTRICAL SAFETY COMMUNICATION CONTEXT

As stated above, standards and associated written procedures are the content of effective electrical safety communication. NFPA 70E, Standard for Electrical Safety in the Workplace, is a key document that provides the content necessary for electrical safety in the workplace. Below is a brief summary of the communication content provided in NFPA 70E:

In addition to the electrical safety content provided in standards and written procedures, worker training, skills, and knowledge of electrical equipment and electrical hazards are the context of effective electrical safety communication. This is why so much emphasis is placed on using qualified electrical workers to work on or around electrical hazards. As stated above, a qualified worker is capable of taking requirements and procedural content and putting it in the appropriate context to perform an electrical work task safely. Some of this context is related to electrical equipment and system reliability and operability. This can only be accomplished with correct or appropriate maintenance. To enhance a workers capability to provide an appropriate context for performing work safely, NFPA 70 provides for some electrical communication context as well:

• Definitions – NFPA 70E, Article 100, provides definitions of terms “essential to the proper application of [the] standard.” The standard also provides informational notes and annexes to assist the worker in understanding the content of the standard. • General Requirements – NFPA 70E, Article 110, provides electrical safety-related work practices and procedures. Requirements associated with the electrical safety program are presented. Key content for the electrical safety program include work procedures, electrical work permits, electrical hazard analysis, and evaluation. • Electrically Safe Work Conditions – NFPA 70E, Article 120, communicates requirements associated with performing an adequate lockout/tagout (LOTO) process for electrical equipment

• Definitions – NFPA 70E, Article 100, provides definitions of terms “essential to the proper application of [the] standard.” Qualified electrical workers should understand and be familiar with these terms.

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Safety Handbook • From NFPA 70E, Article 205.6 – “Equipment, raceway, cable tray, and enclosure bonding and grounding shall be maintained to ensure electrical continuity.” The only way to verify that a facility has maintained electrical continuity in the grounding system is to test and measure that continuity. This testing is typically performed in several steps. First, a fall-of-potential test is performed to verify that the grounding electrode or system is adequately connected to ground. Then many point-topoint tests are performed to verify adequate connection of equipment, raceway, etc. to the grounding electrode. • From NFPA 70E, Article 205.7 – “Enclosures shall be maintained to guard against accidental contact with energized conductors and circuit parts and other electrical hazards.” • From NFPA 70E, Article 205.8 – “Locks, interlocks, and other safety equipment shall be maintained in proper working condition to accomplish the control purpose.”

• General Requirements – NFPA 70E, Article 110, includes responsibilities for owners and contractors to tell each other about known hazards as well as reporting observed safety violations of the standard. Requirements associated with worker training and the electrical safety program are presented. Key contextual elements of the electrical safety program include job briefings and electrical hazard awareness.

• From NFPA 70E, Article 205.9 – “Access to working space and escape passages shall be kept clear and unobstructed.” • From NFPA 70E, Article 210.3 – “Current-carrying conductors (buses, switches, disconnects, joints, and terminations) and bracing shall be maintained to: (1) Conduct rated current without overheating; (2) Withstand available fault current.”

• From NFPA 70E, Article 130.3 – “The arc flash analysis shall be updated when a major modification or renovation takes place. It shall be reviewed periodically, not to exceed five years, to account for changes in the electrical distribution system that could affect the results of the arc-flash hazard analysis.” The arcflash analysis is the basis for selection of arc-flash PPE. If the analysis and associated labeling are not correct, the selected PPE may be inadequate to protect the worker.

• From NFPA 70E, Article 210.4 – “Insulation integrity shall be maintained to support the voltage impressed.” Insulation failure or breakdown is one of the more significant causes of failures for transformers, cables, cable terminations, cable splices, buses, and joints. Because of this, a range of tests has been developed to test and monitor insulation integrity (insulation resistance testing, ac and dc high-potential testing, power-factor testing, polarization index testing, partial discharge testing, VL F tan delta, etc.). Combinations of these tests are typically performed in an effort to determine the overall health of insulation systems.

• From NFPA 70E, Article 205.1 – “Employees who perform maintenance on electrical equipment and installations shall be qualified persons…and shall be trained in, and familiar with, the specific maintenance procedures and tests required.” Not all electrical workers are qualified to perform all electrical tasks. Electrical maintenance and testing activities have evolved into using more sophisticated equipment and techniques. Typically, additional training on the use of this testing equipment is required.

• From NFPA 70E, Article 210.5 – “Protective devices shall be maintained to adequately withstand or interrupt available fault current.” Maintenance, which includes operability testing, must be performed on a periodic basis to ensure that protective devices operate as designed. With the recent requirements associated with arc-flash hazards analysis, correct protective device operation is critical to the accuracy of the arc-flash analysis, while minimizing and mitigating the arcflash hazards.

• From NFPA 70E, Article 205.2 – “A single line drawing, where provided for the electrical system, shall be maintained in a legible condition and kept current.” This is an often overlooked component of any good maintenance program. Having up-todate drawings is a requirement for performing maintenance in a safe and proper manner. It is also critical in determining and implementing proper lockout/tagout processes and procedures.

• From NFPA 70E, Article 225.1 – “Fuses shall be maintained free of breaks or cracks in fuse cases, ferrules, and insulators. Fuse clips shall be maintained to provide adequate contact with fuses. Fuseholders for current-limiting fuses shall not be modified to allow the insertion of fuses that are not current-limiting.” Any good maintenance program for low-voltage and mediumvoltage, fused disconnect switches includes visual inspection, contact resistance testing, and fuse resistance testing. Fuse sizing should be as designed and analyzed. Any change to a fuse size or type requires a review of the coordination and arc-flash studies.

• From NFPA 70E, Article 205.4 – “Overcurrent protective devices shall be maintained in accordance with manufacturers’ instructions or industry consensus standards.”

Safety Handbook • From NFPA 70E, Article 225.3 – “Circuit breakers that interrupt faults approaching their interrupting ratings shall be inspected and tested in accordance with the manufacturer’s instructions.” To feasibly meet this requirement, an accurate short-circuit study, which is usually performed along with the arc-flash analysis, is typically required. Over the past 10 years, the above electrical safety communication context should be well known to any qualified electrical worker. Most employers have provided very specific training associated with electrical safety in the workplace. If a qualified electrical worker is not aware of the requirements discussed above, the worker’s qualifications should be questioned. In summary, effective communication typically considers both content and context. With respect to electrical safety in the workplace, the standards and associated written procedures are the content of effective electrical safety communication. NFPA 70E is a key document that provides the electrical safety content for a qualified worker. Worker training, skills, and knowledge of electrical equipment and electrical hazards provide the context for appropriately or correctly communicating and implementing the electrical safety requirements. This knowledge of the electrical equipment and electrical hazards includes whether correct system documentation, analyses, maintenance and operability are being provided for the equipment. With this information, a qualified worker should be capable of taking requirements and procedural content and putting them in the appropriate context to perform an electrical work task safely.

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Safety Handbook

LOCKOUT/TAGOUT TAKING IT FOR GRANTED NETA World, Winter 2011-2012 Issue By Jim White and Ron Widup, Shermco Industries All of us in the field have had repeated training on lockout/ tagout. NETA technicians can have annual training, then training at each customer’s site, and often several other times throughout the year and their career. It is often the topic of tailgate meetings and safety briefings. It is probably human nature to hear something so often and from so many sources that we go on auto-pilot at times. Instead of going through the procedures deliberately, even the best of us may not hit it as hard as we should. The following true case study illustrates this point. The project involved maintenance work that was being performed by several contractors at a company’s location in the Midwest (the host). The work involved medium-voltage switchgear in a building and an outside substation. The switchgear was of a standard metalclad, drawout, vacuum interrupter design and was in excellent condition. As can be seen in Figure 1, the switchgear also was marked with the single-line on the front of the gear.

Figure 1: Switchgear Involved in the Incident The worker involved in the incident was assigned to clean the switchgear and vacuum bottles in a section of equipment that had been properly locked out, tagged out, tested and grounded. The work on this section of switchgear had been ongoing for a couple of days. One of the other contractors asked the worker to clean and test a circuit breaker cell that was not on the original list of equipment to be maintained. The host company that owned the equipment approved the addition of this circuit breaker cell to the list. The circuit breaker cell was to a bus tie breaker that had been deenergized the evening before, but had been returned to service. (See Figure 2).

Figure 2: Location of the Incident It was believed that it was communicated to all the companies that were considered to be either authorized or affected that the bus tie breaker had been returned to service. Locks, tags and signage were in place from all parties except the worker who was asked to do the maintenance. Since the company that the worker was employed by was not scheduled to perform any maintenance on that particular circuit, the company was not perceived to be affected or authorized when the LOTO was performed. The involved worker had completed a Job Safety Analysis ( JSA) prior to the start of work that day, but did not include the newly-added circuit breaker cell, so the backfeed hazard caused by the tie breaker was not addressed. The affected worker did not place his own locks or tags on the switchgear as it was already secured (see Figure 3). The locks and tags were on the back side of the circuit breaker cubicle. The worker involved in the incident opened the door on the front of the circuit breaker cell in order to perform the assigned maintenance. He did not test the circuit. The worker knelt down on one knee and manually opened the shutters over the bus stabs. Figure 4 shows the exposed energized bus stabs with the shutters open.

Safety Handbook

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Figure 3: Location of the Incident

Figure 5: Burn Injuries to Hand

Figure 4: Exposed Bus Location

Figure 6: Blowout Injury to Knee

As the worker extended his hand to begin cleaning the tie breaker cell, an arc flash and shock to the worker occurred. Other maintenance personnel in the area immediately came to his aid and extinguished the fire on his clothing and called 911. The injured worker was transported to a burn center where he received the appropriate medical attention. The worker survived this incident and received burn injuries to his right hand and a blow-out injury to his knee (Figures 5 and 6). After a fairly long recovery period, this worker should be able to continue on with his life, an option that many people in his situation would not have had under similar circumstances.

Under similar circumstances, companies have been known to fire employees for violating safety rules. That is one approach. He did not test the circuit prior to working on it. He did not complete a JSA. He did not consider how dangerous working bus tie circuits can be. No arc-flash protective clothing or PPE was worn. We could point to several mistakes that were made, but the root cause does not belong entirely to the worker. There were mistakes made by almost all parties involved. The host company approved the additional cell maintenance without considering all the consequences. Neither the host nor the contractor requesting the circuit breaker cell be added to the list advised the affected worker that the circuit had been reenergized. When I was in boot camp our Drill Instructor told us that assume makes an ass out of you and me. It was true then, and it is true today. In this instance, assumptions came into play several times, both by the worker and by the companies involved. The good news is that it did not result in a fatality, but that does not relieve the pain and suffering that the employee had to endure. This same

10 type of scenario is likely repeated at many job sites throughout the U.S. Multiple contractors, dozens, maybe hundreds of workers, power system equipment and devices, all have to be taken into consideration when performing maintenance activities. It can become a blur. People are people, and people make mistakes. That is why we have OSHA, NFPA 70E, procedures, policies, etc. Most, if not all of us have either been involved in accidents or know people who have been. It’s not like it’s a secret that people make mistakes, but to talk to some, they seem to think only others have that failing.

SUMMARY Safety is not about just any one procedure or rule. It’s about slowing down, planning, and executing that plan. There are plenty of tools available to help us: policies, procedures, codes, standards, federal regulations, and state and local laws. I am not about to say that the worker involved in this incident was not taking safety seriously, but he failed to follow some fundamental safety rules like test-before-touch. If he had taken just that one step, there would be nothing to write about. Ron Widup and Jim White are NETA’S representatives to NFPA Technical Committee 70E (Electrical Safety Requirements for Employee Workplaces). Both gentlemen are employees of Shermco Industries in Dallas, Texas a NETA Accredited Company. Ron Widup is President of Shermco and has been with the company since 1983. He is a Principal member of the Technical Committee on “Electrical Safety in the Workplace” (NFPA 70E) and a Principal member of the National Electrical Code (NFPA 70) Code Panel 11. He is also a member of the technical committee “Recommended Practice for Electrical Equipment Maintenance” (NFPA 70B), and a member of the NETA Board of Directors and Standards Review Council. Jim White is nationally recognized for technical skills and safety training in the electrical power systems industry. He is the Training Director for Shermco Industries, and has spent the last twenty years directly involved in technical skills and safety training for electrical power system technicians. Jim is a Principal member of NFPA 70B representing Shermco Industries, NETA’s alternate member of NFPA 70E, and a member of ASTM F18 Committee “Electrical Protective Equipment for Workers.”

Safety Handbook

MediUM-voltage starter control circUit SafeTy iSSUe MEDIUM – VOLTAGE STARTER

Safety Handbook

11

most medium-voltage starters have a recessed plug to accept CONTROL CIRCUIT: SAFETY ISUE an extension cord connection to power up the starter’s control

By aL HavenS,

E-Hazard.com

circuit when the contactor carriage of the starter is in the test World, Winter 2011-2012 Issue position. TheNETA function of the test position is to use external By Al Havens, E-Hazard.com control power and test the operation of the control circuit without energizing the connected motor. The control circuit may have a bond from neutral Most medium-voltage starters have a recessed plugthe to accept an 240/120 VAC PDP extension cord connection to on powerthe up the starter’s control circuit test connection on when the contactor carriage of the starter is in the test position. the controller carriage to Ground The function of the test position is to use external control power Bus frame the energizing carriage. Extension Cord and test the operation of thethe control circuitofwithout the connected motor. The control may have so a bond from This circuit sets up a not obvious Neutral Extension cord shown without connectors to Bus the neutral on the test connection on the controller carriage to the problem for maintenance PDP for clarity frame of the carriage. This sets up a not so obvious problem for personnel. maintenance personnel. Having the control circuit’s neutral bonding to the carriage’s frame allows electrical currenthaving to flow between the 120 Vac power the control circuit’s neutral bonding distribution panel (PDP) through twocarriage’s paths. The firstallows is the electrical normal to the frame current or to flow betweenconductor, the 120 vacof power path, which is through the neutral, grounded the panel (PdP) through two paths. extension cord. The second distribution path is through the neutral bond in The first is the normal path, which is through the PDP, through the facility’s grounding system, conduits and the neutral, or grounded conductor, of the equipment grounding, to theextension carriage frame itself,path then to the cord. The second is through the neutral bond in theon PdP, the neutral bonding jumper on the test connection thethrough carriage. facility’s grounding in system, conduits and These two paths of current flow are illustrated Figure 1. equipment grounding, to the carriage frame itself, then to the neutral bonding This current path is objectionable ground current andjumper does ® on in thethe testNational connection on the Code carriage. . not comply with Article 250.6 Electrical These two paths of current flow are illustrated This ground current is potentially dangerous if the neutral in the in Figure 1.

figure 1 H N G

Medium Voltage MCC Enclosure

Normal Neutral Current Path Starter Carriage

To Starter Control Circuit H

Test Switch in “Test” Position

N CPT

extension cord is not continuous.

The remedial action for existing equipment is the following:

Objectionable Current Path

1. Remove the bond on the carriage frame of the contactor. This is not as dangerous as it sounds. The neutral bond to ground at mediUm-voltaGe starter control circUit safety issUe NETAWORLD • 73 Figure 1 the PDP will function as the appropriate grounded connection With new equipment, insist the manufacturer bond the CPT’s using an extension cord while the controller carriage is in the neutral connection to ground on the enclosure itself, not the test position. contactor carriage frame. Verify that the carriage frame receptacle/ 2. Apply a bond to the frame of the starter enclosure at the control plug for the control circuit has a pin dedicated and connected to power transformer’s (CPT) secondary neutral connection. The the frame of the enclosure, on the enclosure side of the starter and contactor carriage frame will be inherently connected to the to the frame of the carriage on the contactor carriage side of the starter enclosure frame through metal connection of the carriage starter. That guarantees the two frames are electrically bonded. The wheels. Measure the dc resistance between the carriage frame bond will not depend on the carriage wheels making good contact and enclosure after establishing the bond at the CPT’s neutral with the enclosure frame. Thoroughly examine the proposed connection. Use 0.5 ohm as a guideline. Investigate any value starter’s control circuit to make certain there is no neutral bond to greater than that. U se an electronic ohmmeter that can measure the contactor carriage frame shown on the equipment’s drawings. 0.001 ohm.

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Safety Handbook Al Havens brings more than 40 years of electrical safety experience to the classroom, 26 of which as Senior Electrical Engineer for U.S. Gypsum. He has extensive experience in industrial plant and underground mine power distribution upgrades and is expert in the design and commission of high resistance ground, switchgear battery and automatic power factor systems.

Al served as head of the USG Energy Monitoring Task Force and established their NFPA 70E compliance and training programs. He has presented to both the IEEE Electrical Safety Conference and the International Electrical Testing Association (NETA) Conferences on electrical equipment and high resistance grounding, and worked extensively on compliance issues with the Mine Safety and Health Agency (MSHA).

Safety Handbook

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PPE REQUIREMENTS FOR INSTALLATION OF TEMPORARY PROTECTIVE GROUNDS NETA World, Winter 2011-2012 Issue By Scott Blizard and Paul Chamberlain, American Electrical Testing Co., Inc.

The purpose of temporary protective grounds is to protect the personnel servicing the equipment and to create a safe work environment. Prior to servicing a piece of electrical equipment, it is important to ensure that it is in a safe state and to verify zero voltage before applying temporary protective grounds. In many situations, more than one set of grounds or grounding apparatus must be applied. When identifying the placement of temporary protective grounds, ensure all work will be performed within the zone of protection. For correct placement and sizing of temporary protective grounds and grounding apparatus, refer to OSHA 29 CFR 1910.269 Electric Power Generation, Transmission and Distribution Standard. It states under paragraph (n) Grounding for the protection of employees that grounding must be utilized as a means of protecting employees on de-energized lines, and that “For the employee to work lines or equipment as de-energized, the lines or equipment shall be de-energized under the provisions of paragraph (m) of this section and shall be grounded as specified in paragraphs (n)(3) through (n)(9) of this section. However, if the employer can demonstrate that installation of a ground is impracticable or that the conditions resulting from the installation of a ground would present greater hazards than working without grounds, the lines and equipment may be treated as de-energized provided all of the following conditions are met:” 1. The lines and equipment have been deenergized 2. There is no possibility of contact with another energized source

1910.269 then states under (n)(4) that “Protective grounding equipment shall be capable of conducting the maximum fault current that could flow at the point of grounding for the time necessary to clear the fault. This equipment shall have an ampacity greater than or equal to that of No. 2 AWG copper.”

WHAT LEVEL OF PPE IS REQUIRED WHEN INSTALLING TEMPORARY PROTECTIVE GROUNDS? Any work on or near exposed energized equipment that encroaches within the Restricted Approach Boundary or the Arc-Flash Protection Boundary requires some form of additional personal protection. The level of protection required depends on the incident energy level and proximity to the circuit. A copy of the 2012 NFPA 70E, Standard for Electrical Safety in the Workplace© should be referenced prior to beginning the grounding operation. A lot of the tasks can be found within Table 130.7(C) (15)(a), formerly known as Table 130.7(C)(9) in the 2009 version. When using the table, take notice of the notes at the end of the table because they may change the requirements of PPE required to perform the task. Applying protective grounds to a circuit comprised of the same equipment, within the same voltage range, reference Table 130.7(C)(15)(a) and back to (C)(16) to determine what is needed for personal protective equipment when applying the grounds.

3. The hazard of induced voltage is not present.

COVER STORY Table 1

Tasks Performed on Energized Equipment

Hazard / Risk Category

Metal Clad Switchgear, 1 kV Through 38 kV

Rubber Insulating Gloves

Insulated and Insulating Hand Tools

Parameters: Maximum of 35 kA short-circuit current available; maximum of up to 0.2 second (12 cycle) fault clearing time; minimum 36 inches working distance Potential arc-flash boundary with exposed energized conductors or circuit parts using above parameters: 422 inches

Application of temporary protective grounding equipment, after voltage test table 1

4

Y

N

The table terminology now coincides with OShA. It states that they are temporary protective grounds, and that it is being done after voltage test. This means that even with the presence of zero voltage, the

The table terminology now coincides with OShA. It states that they are temporary protective grounds, and that it is being done after voltage test. This means that even with the presence of zero voltage, the application of grounds must be done when wearing personal protective equipment at a hazard / risk Category level 4, with rubber insulating gloves as a means of protecting the personnel. The following Safety Handbook table shows the PPE required for hazard risk Category level 4.

14 Table 2

HAZARD / RISK CATEGORY 4

FR Clothing - Minimum Arc Rating of 40 (Note 1)

FR Protective Equipment

 Arc Rated Long Sleeve Shirt (Note 9)  Arc Rated Pants (Note 9)  Arc Rated Coveralls (Note 9)  Arc Rated Arc Flash Suit Jacket (AR (Note 9)  Arc Rated Arc Flash Suit Pants (AR) (Note 9)  Arc Rated Arc Flash Suit hood (Note 9)  Arc rated Jacket, Parka, or Rainwear (AN)  Hard Hat  FR Hard Hat Liner (AR)  Safety Glasses or Safety Goggles (SR)  Hearing Protection (Ear Canal Inserts)  Arc Rated Gloves (Note 2)  Leather Work Shoes (AN)

The table terminology now coincides with OSHA. It states that 8.  Put on the required level of PPE after verifying that the tAble 2 they are temporary protective grounds, and that it is being done task has a known or calculated Hazard / Risk Category. Application of the clamp the grounded without the use ofPPE the will full level of PPE when after voltage test. This means that even with the to presence of zeroside can be achieved Ensure that no additional be necessary encroaching within approach distance of some pieceprotective of equipment. Clamping the ground voltage, the applicationunless of grounds must be donethe when wearing applying grounds to equipment that has beenCategory removedLevel from service9.andDde-energized should be accomplished using a personal protective equipment at a Hazard / Risk e-energize equipment shotgun stick wearing full gear. Table 4, with rubber insulating gloves as while a means of protecting the 130.7(C)(15)(a) requires gloves to perform the task and 10. Verifyline-to-line that the voltage testing functional thetable notes state the thatPPE theyrequired need to for be rated for the “maximum voltage upondevice which is work will against personnel. The following shows Hazard a known source Risk Category Level 4. be done.” 11. Verify zero voltage, and have someone double check it Application of the clamp to the grounded side can be achieved without the use of the full level of PPE unless encroaching within the approach distance of some piece of equipment. Clamping the ground to equipment that has been removed from service and de-energized should be accomplished using a shotgun stick while wearing full gear. Table 130.7(C)(15)(a) requires gloves to perform the task and the notes state that they need to be rated for the “maximum line-to-line voltage upon which work will be done.”

• WINTER 2011 RECOMMENDED PRACTICES

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12. Reverify that the test device is functional against a known source 13. Apply the grounding side of the clamp and ensure that it is No. 2 AWG or larger ground cable 14. Apply grounds to the equipment utilizing a reach or remote method such as a shotgun

PPe reqUirements for installation of temPorary Protective GroUnds

Here are some valuable steps that should be taken prior to commencing work: 1. Be familiar with the equipment being serviced 2. Check drawings and one-lines 3. Walk the site to identify any physical hazards

15. Remove the PPE when the task is complete

CONCLUSION Refer to industry standards such as the NFPA or OSHA as necessary and wear the required PPE when installing temporary protective grounds. Be safe; when in doubt, always err on the side of caution.

5. Write a switching and tagging order, or utilize the lockout/ tagout procedure specific to the equipment

While reviewing the 2012 NFPA 70E in research for this article, the author noted that 130.8(C)(7) does not exist anywhere within the body of the Standard, except in the reference indicated. The author has submitted a proposal to the NFPA to amend this typographical error.

6. Write a Job Hazard Analysis, and / or the prejob briefing, identifying all site and task specific hazards

REFERENCES

4. Check the equipment for a recent Arc Flash Hazard Analysis

7. Discuss the prejob briefing with coworkers, and see if they have any insight into past successes or failures in dealing with similar tasks

1) O  SHA Standards for General Industry, 29 CFR Part 1910.269, Electric Power Generation, Transmission, and Distribution Standard 2) N  FPA 70E – Standard for Electrical Safety in the Workplace, 2012 and 2009 Editions.

Safety Handbook Paul Chamberlain has been the Safety Manager for American Electrical Testing Co., Inc. since 2009. He has been in the safety field for the past 12 years, working for various companies and in various industries. He received a Bachelor’s of Science degree from Massachusetts Maritime Academy. Scott Blizard is the current Vice President-Chief Operations Officer and the former head of Safety for American Electrical Testing Co., Inc. Scott is a master electrician and a NETA Level 4 Test Technician with over 30 years of experience in the electrical industry.

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Safety Handbook

THE FORGOTTEN WORKPLACE – HOME NETA World, Winter 2011-2012 Issue By Don Brown, Shermco Industries

Have you ever received an electric shock while doing something at home? Most of us have at one time or another. This could have happened for any number of reasons. It could have been a faulty extension cord, or a bad connection to a power tool, or maybe even it was unintentionally touching a bare wire. In any case, it did not feel good. Many people think about their safety while at work but seem to leave it there. They do not take it home with them. If only they could leave the hazards there as well. Unfortunately, it does not happen that way. Most of the time, there are actually more hazards in the home than in the workplace.

WHAT HAZARDS? Everyone is aware of the necessity to maintain the equipment at their workplace, but what about at your home? What happens if you do not take care of your vehicle? Your yard? Your home? Something as simple as checking the receptacles in the walls of your house can let you know that there could be impending problems. Have you ever had to squeeze or spread the prongs of a plug to get it to stay in the receptacle in the wall? Generally, that is caused by the internal contacts becoming worn out. Overheating can cause that as well as the age of the receptacle. If it is used often, the normal wear and tear on the contacts inside the receptacle can just stretch out of place and cause a loose plug. That is one item that can very easily be addressed by the homeowner. Do you unplug the vacuum cleaner by pulling on the cord instead of going “all the way over” to the plug? It is just this kind of action that can start the deterioration of your home electrical system. When replacing the receptacles, do not just take out the old one and put in the new one. Look at the condition of the receptacle itself. If there is some discoloration or obviously burned or scorched surfaces do a little investigating to find out what caused it. Many times it will be no more than a loose connection on the old receptacle. It could, however, be the result of overloading the receptacle. And what about those pesky two-prong receptacles that do not have a ground on them? Believe it or not, there are still a lot of homes that have an inadequate, ungrounded electrical system. Many homeowners have relied on the three prong adapters to help remedy this problem. This is not a good idea at all. If there is no grounding conductor in your electrical outlet, you will only be increasing the potential problems. The photos below show a very good example of what will happen if you use these types of adapters. If you do not have a good, functional ground system in

your home, you are putting yourself at risk of a dangerous, and sometimes fatal, electric shock, or even fire. This is not the type of repair that can be done by the typical homeowner. This kind of work needs to be done by a qualified professional.

WHAT TO LOOK FOR. Look for the abnormal. Use your senses at all times while in your home. Look for something that does not work the way that you think it should. Is the plug loose in the receptacle or does the plug continually fall out while you are working? Do you smell burning insulation? Do you hear a humming coming from the electrical panel? Does an appliance plug feel hot when you unplug it? If you are going to take on the task of replacing a light switch or a receptacle in your house, good for you. But before you do, ask yourself this question – “Do I feel comfortable doing this kind of work?” If not, then you need to contact that qualified electrical contractor to make the repairs. If you do feel comfortable doing this kind of work, you need to take certain precautions prior to starting the work. Rule number one is to turn off the power! You must turn off the power before attempting any type of electrical work, no matter what your skill level. Are you sure that the power is turned off? Many times, home builders will run the circuitry to include the maximum number of receptacles to each circuit breaker. And some times this means tying receptacles from different rooms onto the same circuit, especially on a common wall between two rooms. Invest in a good quality voltage detector that you can use around the house. It does not have to be the most expensive tester, but make sure that it will hold up to repeated use, and the occasional drop test. A good reliable category II or III digital multimeter would be a great investment in your safety around the home. These can be purchased for a reasonable price at most home improvement stores or electrical distributors. Another item that you should invest in is a pair of rubber insulating gloves. Not the same kind of rubber gloves used for dishwashing, but the correct type used in electrical work. Before you start to roll your eyes and think, no way am I going to wear those just to replace a light switch, remember that the most common voltage involved in electrical fatalities is 120 Vac. Once you determine that the power is indeed turned off, you can take off the gloves and do the work.

Safety Handbook

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Example 1. 3-Prong Wall Oulet

Example 4. 3-Prong Adapter, Front View

Example 2. Back of 3-Prong Wall Oulet

circuit breaker in your electrical panel. If a breaker trips, it does it for a reason. In the majority of the cases, a tripped breaker is caused by an overload to the circuit. If the circuit is drawing too many amperes, the breaker will sense it and open. This is a warning to the homeowner. Unfortunately, most homeowners just think this is a bad breaker that has started to trip for no reason other than it is old. Breakers do not normally go bad on a correctly designed system, and if they do trip, it is to protect the wiring of the electrical system. If a breaker trips, look for an overloaded receptacle, one that has more than two devices plugged into it. Although this a bit of an extreme situation, think about the holiday season when all of the decorations are plugged into a wall outlet. Everyone wants to have the best display and the most lights, but if you do not understand the limitations of your electrical system, you can, and more than likely will, have a situation like the one just shown. If this happens in your home, do not try to fix it yourself. This is the time to spend the extra money on a qualified electrical contractor, one that will be able to evaluate the extent of the damage to your home’s wiring.

Example 3. 3-Prong Adapter, Side View HOW DO I REDUCE THE HAZARDS AT HOME? The first thing to do is understand what the hazards are. Then you can look for ways to reduce, or in many cases, eliminate them. Probably the most common hazard to the electrical system in the home is overloading. Plugging in too many devices into a circuit will cause the wiring and the devices (plugs and receptacles) to heat up and fail. In a best case scenario, this overload will be cleared by the

Many people are getting into the do-it-yourself mode of remodeling their homes as the economy gets tougher. This is a great idea for making your home a little more comfortable in trying times, but be careful about how you go about it. Putting a new coat of paint on the walls may seem easy, but pay attention to the details, especially when it comes to painting around receptacles, light switches, and other electrical fixtures. Some folks want these devices to blend into the room so they won’t stand out. That is fine, as long as you take the time to replace them with devices that coordinate with the room décor. Do not just paint over the receptacles and switches.

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As the holiday season approaches, the decorations get pulled out of storage. What condition are they in? How were they stored for the last ten months or so? Were they damaged before being put away last year? These are all questions that need to be asked. Look at the decorations, extension cords, and the strings of lights as you start to pull them out of the storage boxes. Do not just grab and start to pull them out. That is one sure way to break the lights themselves. Do not just grab the plug and put it into the extension cord lying in the same storage box with them. Look each one over before

Safety Handbook plugging it in. If there is one broken light bulb and it is resting on your skin, plugging it in is one sure way to get shocked. And there is the possibility of cuts and broken glass getting stuck in your legs or hands. Pay close attention to how many strings of lights are plugged together. Typically the light manufacturers will place a warning on the boxes giving a maximum number of strings that should be connected together. Read and heed that warning. If you do not, it will cause problems.

Example 7. Painted Wall Oulet WHAT TO DO NEXT Example 5. This Kind of Overload Can Result in This:

Example 6.

Keep an eye on your home. You may be remodeling a room, setting up Christmas decorations, or just putting in a new ceiling fan. If you find anything out of the ordinary, make note of it and get it corrected before it leads to other, more serious issues. If you decide to tackle a project like replacing a light switch or outlet in the wall, make certain that the power is turned off before you start the work. Test the circuit that you will be working on with a reliable test meter. Be sure that all of the connections you make are tight and secure and the wires are not being pinched by cover plates or screws. Use your senses around the house. Look for problems; listen to your electrical panel; smell for burning insulation; and feel for heated plugs, switches, and outlets. But most importantly, do it safely or call a qualified electrical contractor to do the work for you.

Safety Handbook

Example 7. Holiday Lights Don Brown has been involved in the electrical industry for over 35 years – 15 of those specific to electrical testing. He was a master electrician, safety consultant, and business owner. He has consulted for companies such as Intel, Air Liquide, Bell Helicopter, and Chesapeake Energy. Don now serves Shermco Industries as a Senior Training Specialist.

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Safety Handbook

USING PERSONAL PROTECTIVE GROUNDS IN INDUSTRIAL FACILITIES NETA World, Winter 2011-2012 Issue By Lynn Hamrick, Shermco Industries

You are sitting around waiting for the outage to begin. Your task is to perform preventive maintenance on the 15 kV class switchgear lineup feeding a large industrial facility. As seems typical of the situation, an argument is in full force over the need and adequacy of the personal protective grounds being applied. The local contractor intends to use what looks like a modified set of automobile jumper cables. Your supervisor is requiring use of a much more substantial configuration of cables with fancy connectors on each end. He is also requiring that two ground sets be attached so that his workers are working between the ground sets. The customer is trying to resolve the situation. He just wants to start the outage. This is when one of the contractor’s men offers a statement like, “We used to just throw a logging chain across the bus. If it came back out at you, it wasn’t dead.” During times such as those described above, it is nice to know the requirements associated with use and selection of personal protective grounds. The primary purpose of personal protective grounding is to provide adequate protection against electrical shock causing death or injury to personnel while working on de-energized lines or equipment. For medium- and high-voltage applications, protective grounds are required as part of the lockout/tagout program. This is accomplished by grounding and bonding lines and equipment to limit contact or exposure to voltages at the work site to a safe level if the lines or equipment are accidentally energized from any source of hazardous energy. The greatest source of hazardous energy in most cases is direct energization of lines or equipment from the power system. Other sources of hazardous energy may include: • Stored energy (capacitors and cables) • Static build-up • Electromagnetic coupling • High-voltage testing • Back-feed from atypical power sources Personal protective grounding is intended for temporary grounding during installation, maintenance, and repair or modification of lines and equipment. It is not intended to substitute for a prolonged or permanent plant or station equipment grounding connection which should be provided by permanent grounding and wiring methods. Any employee working on de-energized mediumand high-voltage equipment is responsible for understanding protective grounding requirements and procedures. Further, facility managers and supervisors are responsible for ensuring

that workers are knowledgeable of and comply with grounding procedures. Only trained and qualified workers shall apply and remove temporary personal protective grounds. OSHA requirements for personal protective grounding at an industrial facility is actually found in 29 CFR 1910.269, the standard typically associated with utility systems. As it states in the note from 1910.269(a)(1)(i)(A), “(t)he types of installations covered … include the generation, transmission, and distribution installations of electric utilities, as well as equivalent installations of industrial establishments.” Medium-voltage electrical infrastructure within an industrial facility is an equivalent installation. In accordance with 1910.269(n)(2), “For the employee to work lines or equipment as de-energized, the lines or equipment shall be de-energized … and shall be grounded as specified in paragraphs (n)(3) through (n) (9) of this section.”

PROTECTIVE GROUNDS – SIZING AND SELECTION Protective ground cables and associated grounding equipment shall meet the following requirements: • Personal protective grounds shall be capable of conducting the maximum fault current that could flow at the point of grounding for the time necessary to clear the fault. This equipment shall have an ampacity greater than or equal to that of No. 2 AWG copper. • Personal protective grounds shall have an impedance low enough to cause immediate operation of protective devices in case of accidental energizing of the lines or equipment. This translates into being capable of carrying the maximum av ailable fault current, including dc offset current due to waveform asymmetry, for high values of fault circuit impedance X/R ratio.

Table 1

Safety Handbook The guidelines for determining the adequacy of personal protective grounds are contained in ASTM F855-2004, Standard Specifications for Temporary Grounding Systems to Be Used on De-Energized Electric Power Lines and Equipment. Based on information in ASTM F855, Table 1 is what we are using in the field for evaluating the adequacy of protective grounds. Select protective ground sets which are easy to apply. This includes considerations associated with the field application conditions and minimizing preparation and installation time. Standardized ground set configuration, to the extent practical, is desirable at each location to keep the number of sizes and types to a minimum. The ground sets should be fabricated as an assembly of suitably rated components (conductor, ferrules, and clamps) to withstand thermal and electromechanical stresses imposed while conducting fault current (see Figure 1). It is also recommended that the ground sets be stored and transported properly to avoid damage and ensure that the ground sets are maintained in good working order.

PROTECTIVE GROUNDS – LOCATION The guiding principle for protective grounding in facilities is that the grounds should be installed as close to the workers as practical in order to provide an effective current shunt around the body and to limit exposure voltage. Keep in mind that the conductor-end and ground-end clamps of protective grounds should be connected near the locations where workers will likely contact parts of equipment that may inadvertently become energized. The protective grounds should be connected directly to the equipment, bus, or conductors to be grounded. No impedance or device (circuit breaker, disconnect switch, transformer, line trap, etc.) shall be permitted between the point of connection of the protective grounds and the location of contact by the workers. Additionally, avoid connecting the ground-end clamps to a grounding point (plant grounding conductor) that is not bonded directly to permanently grounded parts of the equipment to be worked on. Otherwise, ground loops may be formed with embedded ground mat conductors in plant concrete which can significantly increase the exposure voltage.

21 PROTECTIVE GROUNDS – APPLICATION AND REMOVAL Before any personal protective grounds are installed, the applicable lines and equipment shall be tested and found absent of nominal voltage. This typically involves measuring the voltage with a voltage sensor on the end of a hot stick. Appropriate personnel protective equipment and safety precautions consistent with the circuits being energized should be utilized when testing for voltage and while applying the grounds. When attaching the grounds, the ground-end connection shall be attached first, and then the other ends shall be attached by means of a live-line tool. When removing protective grounds, the connections shall be removed from the line or equipment using a live-line tool before the groundend connection is removed. Protective grounds may be removed temporarily to accommodate tests. During those tests, it is the responsibility of the tester and owner to ensure that workers use insulating equipment and are isolated from any hazards. Also, the tester and owner should institute any additional measures as may be necessary to protect each exposed worker from the previously grounded lines and equipment becoming energized. The general rule for on the job personal electrical safety around de-energized lines and equipment is the lines and equipment shall be considered energized until protective grounds are installed. Until grounded, minimum approach distances apply with regard to the use and application of personnel protective equipment and procedures. Further, personal protective grounds must be designed, fabricated, and applied in a manner that satisfies the following basic criteria: • Maximize personal safety while working on de-energized high voltage equipment through the use of appropriate protective grounding equipment, procedures, and training • Limit work site exposure voltages to a safe level during accidental energization • Ensure that protective grounds will not fail under the most severe fault conditions • Provide the final energy barrier in the facility lockout/tagout (LOTO) program under direct control of personnel at the worksite.

Figure 1

Lynn Hamrick brings over 25 years of working knowledge in design, permitting, construction, and startup of mechanical, electrical, and instrumentation and controls projects as well as experience in the operation and maintenance of facilities. Lynn is a Professional Engineer, Certified Energy Manager and has a BS in Nuclear Engineering from the University of Tennessee.

VOLUME 2 SAFETY HANDBOOK

VOLUME 2

SERIES II

ANDBOOK

Published By

IRISS Sponsored by Published by NETA - The InterNational Electrical Testing Association

AFETY

SERIES II

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Safety Handbook

WHEN IS AN ENERGIZED ELECTRICAL WORK PERMIT REQUIRED? NETA World, Winter 2011-2012 Issue By Lynn Hamrick, Shermco Industries Most questions associated with the need for an energized electrical work permit (EEWP) have to do with the performance of the following specific work tasks:

As a basis for the discussion, the requirements from NFPA 70E, Electrical Safety in the Workplace, 2012 Edition, will be used. From NFPA 70E, Article 130.1:

• Perform visual inspections ofinfrared (IR)surveys of energized circuits

“(B) ENERGIZED ELECTRICAL WORK PERMIT

• Removal or installation of bolted covers that exposes energized circuits • Opening or closing hinged covers that exposes energized circuits • Work on energized electrical conductors or circuit parts • Application of safety grounds • Insertion or removal of equipment from energized circuits • Switch operation of energized equipment In this article, each of these work tasks will be discussed with regard to the need for processing an EEWP prior to performing the work.

(1) When Required. When working within the limited approach boundary or the arc flash boundary of exposed energized electrical conductors or circuit parts that are not placed in an electrically safe work condition,… work to be performed shall be considered energized electrical work and shall be performed by written permit only. (2) E  lements of Work Permit. The energized electrical work permit shall include, but not be limited to, the following items: 1. Description of the circuit and equipment to be worked on and their location 2. Justification for why work must be performed in the energized condition 3. Description of the safe work practices to be employed 4. Results of the shock hazard analysis a. Limited approach boundary b. Restricted approach boundary c. Prohibited approach boundary d. Necessary shock personal and other protective equipment to safely perform the assigned task 5. Results of the arc flash analysis a. Available incident energy or hazard/risk category b. Necessary personal protective equipment to safely perform the assigned task c. Arc flash boundary 6. Means employed to restrict the access of unqualified persons from the work area 7. Evidence of completion of a job briefing, including a discussion of any job-specific hazards 8. Energized work approval (authorizing or responsible management, safety officer, or owner, etc.) signatures

Safety Handbook (3) Exemptions to Work Permit. Work performed within the limited approach boundary of energized electrical conductors or circuit parts by qualified persons related to tasks such as testing, troubleshooting, and voltage measuring shall be permitted to be performed without an energized work permit, if appropriate safe work practices and personal protective equipment…. are provided and used. If the purpose of crossing the limited approach boundary is only for visual inspection and the restricted approach boundary will not be crossed, then an energized electrical work permit shall not be required. With NFPA 70E – 2009, the language of this article led one to focus on using the EEWP when shock hazards were present with an implied applicability for arcflash hazards through the information required for personal protective equipment (PPE) selection and application. With the newly issued NFPA 70E – 2012, the language has been revised to require an EEWP when either a shock hazard or an arc-flash hazard is present. This was a needed clarification to the standard that eliminates some of the questions associated with implementing the EEWP process. Prior to discussing the most-asked questions on EEWP application, it should be noted that appropriate PPE and planning for the hazards encountered is required whether an EEWP is required or not. This is the case with EEWP-exempt work, as well as EEWP-related work. The following discussions will deal with whether or not an EEWP should be required for the work tasks previously identified as most used. The recommendations presented are those of the author. Final determination and implementation of site-specific requirements are the responsibility of facility owners. They should consider their specific work tasks and select the appropriate work rules and processes for their facility which best fit their interpretation of the standard. In general, when performing work tasks which historically have increased the probability of a hazard and/or will require physically interacting with the energized circuit, an EEWP should be required.

Perform visual inspection or IR surveys of energized circuits. Visual inspections and IR surveys should be considered

testing or troubleshooting activities. The standard specifically states that, from a shock hazard standpoint, this work task does not require an EEWP if the restricted boundary is not breached. However, further clarification should be provided with regard to requiring an EEWP when the arc-flash boundary is breached, which is the case when performing many visual inspections or IR surveys. In general, when performing work tasks which historically increase the probability of a hazard and/or will physically interact with or cause a change in the energized circuit, an EEWP should be required. Given this statement, the decision to require that an EEWP be provided to perform visual inspection or IR surveys is dependent on what work tasks are required to accommodate the inspection or survey. If a worker must simply open a hinged door to perform the inspection/survey, no EEWP should be required since there is no increase in the probability of a hazard and there

23 is no physical interaction with the energized circuit. However, if the worker must remove bolted covers to perform the inspection or survey, an EEWP should be required due to an increase in the probability of the hazard associated with removing bolts and the cover. As stated above, the appropriate PPE for the hazard is required whether an EEWP is required or not.

Removal or installation of bolted covers that exposes energized circuits. Any work task that includes the removal or

installation of bolted covers associated with exposed energized circuits should require that an EEWP be performed. Historically, this task has been shown to increase the probability of the hazard.

Opening or closing hinged covers that exposes energized circuits. Work tasks that include the opening or closing of hinged covers associated with exposed energized circuits should require an EEWP unless this task is being performed as part of a testing, troubleshooting, and voltage measuring effort.

Work on energized electrical conductors or circuit parts.

Work tasks that include working on energized electrical conductors or circuit parts should require an EEWP unless these tasks are being performed as part of a testing, troubleshooting, and voltage measuring effort. • Resetting thermal overloads should be considered part of a testing and troubleshooting effort as long as this activity is performed such that there is no increase in the probability of a hazard and there will be no automatic change in the energized circuit while exposed.

Replacing blown fuses should also be considered part of a • testing and troubleshooting effort. However, replacing blown fuses presents a unique challenge. Fuses within power circuits that are greater than 50V should not be replaced while the portion of the circuit that contains the fuse and fuseholder is energized. Therefore, the portion of the circuit that includes the fuse and fuseholder should be placed in a deenergized state by going throughan appropriate lockout/tagout (LOTO) process to accommodate the fuse replacement. Unfortunately, there may still be exposed energized circuit parts present while the fuse is being replaced in the now deenergized portion of the circuit (i.e., the line side of the associated disconnect for the circuit). Appropriate PPE requirements and safety precautions should be implemented during the fuse replacement process to mitigate any increased probability of the hazard and physical interaction with the energized portion of the circuit. Implementing design changes to a circuit (i.e., the thermal • overload is modified or a different fuse type or size is installed) should require an EEWP to ensure that the safety-related aspects of the change are adequately considered. These aspects should include operability review of the circuit as well as any impacts on the arc-flash analysis for the circuit. Additionally, any change to the protective system should include written authorization prior to implementation.

24 • Application of safety grounds. The application of safety grounds is typically part of an established LOTO or clearance process. In most cases, an EEWP may not be required. However, in some cases, the LOTO process may result in a power circuit configuration modification (i.e., using an alternate power source) such that the available short-circuit current to the circuit is not the same as the analyzed hazard. This change could affect the required sizing of the safety grounds. In these cases, a specific EEWP associated with the application of safety grounds should be considered so that appropriate analysis and written authorization for the change is provided. It is the responsibility of the qualified worker to recognize this configuration change during the job planning and job briefing process and require the appropriate process prior to application of the safety grounds.

Insertion or removal of equipment from energized circuits.

Any work task that includes the insertion or removal of electrical equipment from energized circuits should require that an EEWP be performed. These tasks include the following: • Remove/install circuit breakers or fused switches in lighting panels; • Insertion or removal of motor control center buckets; • Insertion or removal (racking) of circuit breakers or starters in switchgear cubicles; • Insertion or removal of fused switches from bus ducts. Historically, these tasks have been shown to increase the probability of the hazard. Switch operation of energized equipment. As clarification, this discussion applies to switch operations of energized electrical distribution equipment where there is a known hazard. When switch operations are performed with no equipment guards in place (i.e., the door open), an EEWP should be required since known hazards are present unless this task is being performed as part of a testing, troubleshooting, and voltage measuring effort. Technically, for switch operations with the door closed, there is no exposed circuitry due to guarding. Most mediumvoltage (1 kV to 38 kV) equipment includes safety interlocks such that switching operations can only be performed with guards in place (i.e., the door closed). With guards in place, the shock hazard is eliminated. Some interpretations of the standard suggest that there is no arcflash hazard when the guards are in place. Typically, arc-flash hazard analyses are performed with the assumption that the circuit is exposed and energized, not guarded. Realistically, there may be an arc-flash hazard even with all guards in place. With high current, low voltage (