electrical codes standards recommended practices and regulations an examination of relevant safety considerations pdf

Electrical Codes, Standards, Recommended Practices and Regulations www.Technicalbookspdf.com This page intentionally left blank www.Technicalbookspdf.com Electrical Codes, Standards, Recommended Practices and Regulations An Examination of Relevant Safety Considerations Robert J Alonzo P.E AMSTERDAM  BOSTON  HEIDELBERG  LONDON  NEW YORK  OXFORD  PARIS SAN DIEGO  SAN FRANCISCO  SINGAPORE  SYDNEY  TOKYO William Andrew is an imprint of Elsevier www.Technicalbookspdf.com William Andrew is an imprint of Elsevier The Boulevard, Langford Lane, Kidlington, Oxford, OX5 1GB, UK 30 Corporate Drive, Suite 400, Burlington, MA 01803, USA First edition 2010 Copyright ª 2010, Robert J Alonzo Published by Elsevier Inc All rights reserved The right of Robert J Alonzo to be identified as the author of this work has been asserted in accordance with the Copyright, Designs and Patents Act 1988 No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher Details on how to seek permission, further information about the Publisher’s permissions policies and our arrangement with organizations such as the Copyright Clearance Center and the Copyright Licensing Agency, can be found at our website: www.elsevier.com/permissions This book and the individual contributions contained in it are protected under copyright by the Publisher (other than as may be noted herein) Notices Knowledge and best practice in this field are constantly changing As new research and experience broaden our understanding, changes in research methods, professional practices, or medical treatment may become necessary Practitioners and researchers must always rely on their own experience and knowledge in evaluating and using any information, methods, compounds, or experiments described herein In using such information or methods they should be mindful of their own safety and the safety of others, including parties for whom they have a professional responsibility To the fullest extent of the law, neither the Publisher nor the authors, contributors, or editors, assume any liability for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions, or ideas contained in the material herein British Library Cataloguing in Publication Data Alonzo, Robert J Electrical codes, standards, recommended practices and regulations: an examination of relevant safety considerations Electrical engineering–Safety measures Electrical engineering–Safety regulations Electrical engineering–Standards I Title 621.3’0289-dc22 Library of Congress Control Number: 2009938942 ISBN: 978-0-8155-2045-0 For information on all William Andrew publications visit our website at elsevierdirect.com Printed and bound in the United States of America 09 10 11 12 11 10 www.Technicalbookspdf.com Contents Preface xi Acknowledgments xiii Chapter 1: Who, What, Where, When, Why, and How? Codes Standards Recommended Practices Who, What, Where, When, and How American National Standards Institute (ANSI) International Electrotechnical Commission (IEC) International Organization for Standardization 12 Association of Edison Illuminating Companies (AEIC) 16 American Institute of Chemical Engineers (AIChE) 18 American Petroleum Institute (API) 18 ASTM International 20 Canadian Standards Association (CSA) 22 Council for Harmonization of Electrotechnical Standards of the Nations of the Americas (CANENA) 23 Illuminating Engineering Society of North America 25 The Instrumentation, Systems, and Automation Society 26 FM Global 31 Institute of Electrical and Electronic Engineers (IEEE) 32 Insulated Cable Engineers Association, Inc (ICEA) 34 NACE International 36 National Electrical Manufacturers Association (NEMA) 38 National Fire Protection Association (NFPA) 41 Underwriters Laboratories, Inc (UL) 44 Occupational Health and Safety Administration (OSHA) 46 References 50 Chapter 2: American versus Global 55 Standards Harmonization 63 Standards Comparison 63 Thermal Overload Relays 68 Electrical Classified Area Equipment 69 v www.Technicalbookspdf.com vi Contents Equipment Enclosure Differences 71 Conclusions 75 References 77 Chapter 3: The Authority Having Jurisdiction (AHJ) 79 AHJ Adopted Codes and Standards 80 Building Codes 81 Electrical Code 82 Fire Codes 84 Life Safety Code 86 AHJ Process 87 Nationally Recognized Testing Laboratories (NRTL) 89 Owner Authority Having Jurisdiction 89 Federal Authority Having Jurisdiction 91 The Occupational Safety and Health Review Commission 95 State Jurisdiction and State Plans 96 References 98 Chapter 4: Nationally Recognized Testing Laboratories (NRTLs) 101 Listed NRTLs 102 Definitions 104 NRLT Standards Development 106 References 107 Chapter 5: Common Threads 109 Common Threads 109 NFPA 101, Life Safety Code – Common Threads 110 Adoption of NFPA 70, National Electrical Code 112 Low-Voltage Power Distribution and Service Entrance Equipment 112 Surge Protection Devices (SPD) 126 Disconnect Switches 127 Circuit Breakers Operating at 1000 Volts or Less 129 Ground Fault Protection Devices 131 Electrical Equipment Terms Review 132 Switchgear 133 Panelboards 133 Transformers 134 Motor Control Center (MCC) – 600 Volts 134 Personal Protective Equipment 136 Busway 139 References 140 www.Technicalbookspdf.com Contents vii Chapter 6: CFR 1910 versus CFR 1926 143 US Department of Labor 143 Hazardous Energy Control 147 Energy Control Program 153 1910.147(c)(2) Lockout/Tagout 153 1910.147(c)(3) Full Employee Protection 154 Energy Control Procedures 154 Protective Materials and Hardware 155 Periodic Inspection 156 Training and Communication 157 Tagout System 160 Employee Retraining 160 Energy Isolation/Notification of Employees 161 Control Application 161 Release from Lockout/Tagout 164 Additional Requirements 164 Group Lockout or Tagout/Outside Personnel (Contractors, etc.) 165 Electric Power Generation, Transmission, and Distribution 166 US Department of Energy (DOE) 172 References 178 Chapter 7: Developing Electrical Safe Work Practices 183 General 183 Safe Operating Procedures 184 Work Task Permit Requirements 185 Documentation Requirements 188 Lockout/Tagout Procedures 188 Safety System Bypassing 188 Operating or Energized Equipment Work Procedures 189 Safety Inspection and Testing Requirements 190 Work Experience and Training Requirements 190 Safety Equipment Requirements 190 Static Electricity Generation Prevention 192 Fire Watch Requirements 192 Minimum Lighting Levels 193 Compliance Audits 193 Safe Work Practices 194 Lockout/Tagout 194 Work on Energized Equipment 195 Clearances and Approach Distances 195 Alerting Techniques 197 Energized and De-Energization of Power Circuits 197 Work Near Overhead Power Lines 197 www.Technicalbookspdf.com viii Contents Confined Work Spaces 198 Conductive Materials, Equipment, Tools, and Apparel 198 Housekeeping Duties 198 Protective Equipment and Tools 199 Installation, Operation, and Maintenance Considerations 199 Welding 199 Batteries 202 Motor Control 203 Medium- and High-Voltage Equipment 204 Molded Case Circuit Breaker Panels 205 Wiring Connections 206 Cord Sets and Attachment Cords 207 Electrical Receptacles 208 Light Fixtures 209 Rotating Equipment 209 Wiring Considerations 210 Conduit Seals and Fittings 210 Energized Equipment 211 References 211 Chapter 8: Motors, Generators, and Controls 213 Motors and Generators General Types 215 Single-Phase Induction Motors 219 Equipment Specification Preparation 220 Motor and Generator Standards 221 Motor Control and Protection 221 Overload Relays 240 DC Manual and Magnetic Controllers 242 AC Combination Motor Controllers 242 Adjustable Speed Drives 244 Harmonic Mitigation 249 References 253 Chapter 9: Electrical Hazardous (Classified) Area Design and Safe Work Practices 257 Area Classification Boundaries 264 Equipment Temperature 266 Hazardous Area Equipment 268 Definitions: Flammable and Combustible Gases and Vapors Equipment Protection Techniques 270 Explosionproof 277 Purged and Pressurized 278 Intrinsically Safe Circuit 278 www.Technicalbookspdf.com Contents ix Nonincendive Circuits 279 Encapsulation 279 Flameproof 285 Increased Safety 287 Powder Filling 290 Type of Protection ‘‘n’’ Techniques 290 Oil Immersion 290 Definitions – Combustible Dust, Fibers, and Flyings Protection Techniques 291 Dust-ignitionproof 291 Dusttight 291 Hermetically Sealed 293 Hazardous (Classified) Area Equipment Standards 293 North American Equipment Markings 293 Zone Equipment Markings 296 References 300 Chapter 10: Wire, Cable, and Raceway 305 General 305 Definitions 305 Conductor Material 307 Insulation Material 308 Ampacity 309 Power and Control Cables 310 Communications Cable 339 Ethernet Cabling 343 Instrumentation Cable 354 Power-Limited Tray Cable (PLTC) 356 Instrumentation Tray Cable (ITC) 357 Fire Alarm Cable 357 Power-Limited Fire Alarm (PLFA) Cable 358 Ethernet and Optical Fiber Cables 358 Temperature Detector Cables 358 Electrical Raceway, Conduit, and Cable Tray 359 Cable Support and Restraint Systems 364 References 373 Chapter 11: Transformers, Capacitors, and Reactors 375 Transformers 375 Transformer Classifications 376 Voltage and Power Ratings 378 Transformer Tests 381 Resistance Test 381 Winding Turns Ratio Test 381 www.Technicalbookspdf.com 482 Appendix C TABLE C.9 Comparison 1910.269 v 1910.147 Requirements: Lockout/Tagout Application/Application of Controldcont’d 29 CFR 1910.269 {Lockout/Tagout Application} [Application of Control] 29 CFR 1910.147 1910.269(d)(6)(ii) The machine or equipment shall be turned off or shut down using the procedures established for the machine or equipment An orderly shutdown [must] {shall} be [utilized] {used} to avoid any additional or increased hazard{s} [(s)] to employees as a result of the equipment stoppage 1910.147(d)(2) 1910.269(d)(6)(iii) All energy isolating devices that are needed to control the energy to the machine or equipment shall be physically located and operated in such a manner as to isolate the machine or equipment from energy source{s} [(s)] 1910.147(d)(3) 1910.269(d)(6)(iv) Lockout or tagout devices where used shall be affixed to each energy isolating device by authorized employees 1910.147(d)(4)(i) 1910.269(d)(6)(iv)(A) Lockout devices[, where used,] shall be [affixed] attached in a manner that will hold the energy isolating devices in a ‘‘safe’’ or ‘‘off ’’ position 1910.147(d)(4)(ii) 1910.269(d)(iv)(B) Tagout devices[, where used,] shall be affixed in such a manner as will clearly indicate that the operation or movement of energy isolating devices from the ‘‘safe’’ or ‘‘off ’’ position is prohibited 1910.147(d)(4)(iii) 1910.269(d)(iv)(B)(1) Where tagout devices are used with energy isolating devices designed with the capability of being locked {out}, the tag attachment shall be fastened at the same point at which the lock would have been attached 1910.147(d)(4)(iii)(A) 1910.269(d) (6)(iv)(B)(2) Where a tag cannot be affixed directly to the energy isolating device, the tag shall be located as close as safely possible to the device, in a position that will be immediately obvious to anyone attempting to operate the device 1910.147(d)(4)(iii)(B) 1910.269(d)(6)(v) Following the application of lockout or tagout devices to energy isolating devices, all potentially hazardous stored or residual energy shall be relieved, disconnected, restrained, or otherwise rendered safe 1910.147(d)(5)(i) 1910.269(d)(6)(vi) If there is a possibility of reaccumulation of stored energy to a hazardous level, verification of isolation shall be continued until the servicing or maintenance is completed or until the possibility of such accumulation no longer exists 1910.147(d)(5)(ii) 1910.269(d)(6)(vii) {Before} [Prior to] starting work on machines or equipment that have been locked out or tagged out, the authorized employee shall verify that isolation and {deenergizing} [deenergization] of the machine or equipment have been accomplished {If normally energized parts will be exposed to contact by an employee while the machine or equipment is deenergized, a test shall be performed to ensure that these parts are deenergized.} 1910.147(d)(6) [Brackets] indicate verbiage included in 1910.147 {Brackets} indicate verbiage included in 1910.269 Appendix C TABLE C.10 483 Comparison 1910.269 v 1910.147 Requirements: Release from Lockout/Tagout 29 CFR 1910.269 {Release from lockout/tagout} [Release from lockout or tagout] 29 CFR 1910.147 1910.269(d)(7) Before lockout or tagout devices are removed and energy is restored to the machine or equipment, procedures shall be followed and actions taken by the authorized employee{s} [(s)] to ensure the following: 1910.147(e) 1910.269(d)(7)(i) The work area shall be inspected to ensure that nonessential items have been removed and [to ensure] that machine or equipment components are operationally intact 1910.147(e)(1) 1910.269(d)(7)(ii) The work area shall be checked to ensure that all employees have been safely positioned or removed 1910.147(e)(2)(i) 1910.269(d)(7)(iii) After lockout or tagout devices have been removed and before a machine or equipment is started, affected employees shall be notified that the lockout or tagout devices {s} [(s)] have been removed 1910.147(e)(2)(ii) 1910.269(d)(7)(iv) Each lockout or tagout device shall be removed from each energy isolating device by the authorized employee who applied the lockout or tagout device {However, if that employee is not available to remove it, the} [Exception to paragraph (e)(3): When the authorized employee who applied the lockout or tagout device is not available to remove it, that] device may be removed under the direction of the employer, provided that specific procedures and training for such removal have been developed, documented, and incorporated into the employer’s energy control program The employer shall demonstrate that the specific procedure provides {a degree of} [equivalent] safety {equivalent to that provided by} [to] the removal of the device by the authorized employee who applied it The specific procedure shall include at least the following elements: 1910.147(e)(3) 1910.269(d)(7)(iv)(A) Verification by the employer that the authorized employee who applied the device is not at the facility; 1910.147(e)(3)(i) 1910.269(d)(7)(iv)(B) Making all reasonable efforts to contact the authorized employee to inform him or her that his or her lockout or tagout device has been removed; and 1910.147(e)(3)(ii) 1910.269(d)(7)(iv)(C) Ensuring that the authorized employee has this knowledge before he or she resumes work at that facility 1910.147(e)(3)(iii) [Brackets] indicate verbiage included in 1910.147 {Brackets} indicate verbiage included in 1910.269 484 Appendix C TABLE C.11 Comparison 1910.269 v 1910.147 Requirements: Additional Requirements 29 CFR 1910.269 {Additional Requirements} [Additional Requirements] 29 CFR 1910.147 1910.269(d)(8)(i) {If the} [In situations in which] lockout or tagout devices must be temporarily removed from energy isolating devices and the machine or equipment must be energized to test or position the machine, equipment, or component thereof, the following sequence of actions shall be followed: 1910.147(f)(1) 1910.269(d)(8)(i)(A) Clear the machine or equipment of tools and materials in accordance with paragraph {(d)(7)(i)} [(e)(1)] of this section; 1910.147(f)(1)(i) 1910.269(d)(8)(i)(B) Remove employees from the machine or equipment area in accordance with paragraphs {(d)(7)(ii) and (d)(7)(iii)} [(e)(2)] of this section; 1910.147(f)(1)(ii) 1910.269(d)(8)(i)(C) Remove the lockout or tagout devices as specified in paragraph {(d)(7)(iv)} [(e)(3)] of this section; 1910.147(f)(1)(iii) 1910.269(d)(8)(i)(D) Energize and proceed with the testing or positioning; and 1910.147(f)(1)(iv) 1910.269(d)(8)(i)(E) Deenergize all systems and reapply energy control measures in accordance with paragraph {(d)(6)} [(d)] of this section to continue the servicing {or} [and/or] maintenance 1910.147(f)(1)(v) [Brackets] indicate verbiage included in 1910.147 {Brackets} indicate verbiage included in 1910.269 Appendix C 485 TABLE C.12 Comparison 1910.269 v 1910.147 Requirements: Group Lockout or Tagout/Outside Personnel (Contractors, etc.) 29 CFR 1910.269 {Group Lockout or Tagout/Outside Personnel} [No Heading] 29 CFR 1910.147 1910.269(d)(8)(ii) When servicing or maintenance is performed by a crew, craft, department, or other group, they shall {use} [utilize] a procedure which affords the employees a level of protection equivalent to that provided by the implementation of a personal lockout or tagout device 1910.147(f)(3)(i) 1910.269(d)(8)(ii) Group lockout or tagout devices shall be used in accordance with the procedures required by {paragraphs (d)(2)(iii) and (d)(2)(iv)} [paragraph (c)(4)] of this section including, but not limited to, the following specific requirements: 1910.147(f)(3)(ii) 1019.269(d)(8)(ii)(A) Primary responsibility{shall be} [is] vested in an authorized employee for a set number of employees working under the protection of a group lockout or tagout device (such as an operations lock); 1910.147(f)(3)(ii)(A) 1019.269(d)(8)(ii)(B) Provision shall be made for the authorized employee to ascertain the exposure status of all individual group members with regard to the lockout or tagout of the machine or equipment{;} [and] 1910.147(f)(3)(ii)(B) 1019.269(d)(8)(ii)(C) When more than one crew, craft, department, or other group is involved, assignment of overall job-associated lockout or tagout control responsibility{shall be given} to an authorized employee designated to coordinate affected work forces and ensure continuity of protection; and 1910.147(f)(3)(ii)(C) 1019.269(d)(8)(ii)(D) Each authorized employee shall affix a personal lockout or tagout device to the group lockout device, group lockbox, or comparable mechanism when he or she begins work and shall remove those devices when he or she stops working on the machine or equipment being serviced or maintained 1910.147(f)(3)(ii)(D) 1910.269(8)(iii) [Specific] Procedures shall be {used} [utilized] during shift or personnel changes to ensure the continuity of lockout or tagout protection, including provision for the orderly transfer of lockout or tagout device protection between off-going and on-coming employees, to minimize {their} exposure to hazards from the unexpected {energizing} [energization] or startup of the machine or equipment or from the release of stored energy 1910.147(f)(4) (Continued) 486 Appendix C TABLE C.12 Comparison 1910.269 v 1910.147 Requirements: Group Lockout or Tagout/Outside Personnel (Contractors, etc.)dcont’d 29 CFR 1910.269 {Group Lockout or Tagout/Outside Personnel} [No Heading] 29 CFR 1910.147 1910.269(d)(8)(iv) Whenever outside servicing personnel are to be engaged in activities covered by {paragraph (d) of this section,} [the scope and application of this standard,] the on-site employer and the outside employer shall inform each other of their respective lockout or tagout procedures{,} [.] 1910.147(f)(2)(i) 1910.269(d)(8)(iv) {, and each} [The on-site] employer shall ensure that his or her personnel understand and comply with restrictions and prohibitions of the energy control procedures being used 1910.147(f)(2)(ii) [Brackets] indicate verbiage included in 1910.147 {Brackets} indicate verbiage included in 1910.269 Sources: Regulations (Standards – 29 CFR) The Control of Hazardous Energy (Lockout/Tagout) – 1910.147 1: US Department of Labor website: http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table¼STANDARDS&p_id¼9804 Regulations (Standards – 29 CFR) Electric Power Generation, Transmission, and Distribution – 1910.269: US Department of Labor website: http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table¼STANDARDS&p_id¼9868 APPENDIX D Occupational Safety and Health Administration Standard Interpretations 29 CFR 1910.6; 1910.147; 1910.147(c)(4)(ii) US Department of Labor Occupational Safety and Health Administration 200 Constitution Avenue, NW Washington, DC 20210 Standard Interpretations: 11/10/2004 – Recognition of ANSI/ASSE Z244.1-2003 ‘‘Control of Hazardous Energy – Lockout/Tagout and Alternative Methods’’ consensus standard [1] Standard Number: 1910.6; 1910.147; 1910.147(c)(4)(ii) November 10, 2004 Mr xxxxxxxx Chairman, Z244 ASC xxxxxxxx xxxxxxxx Dear Mr xxxx: This is in response to your March 22, 2004 letter to John Henshaw, Assistant Secretary for the Occupational Safety and Health Administration (OSHA) Your letter seeks recognition of the revised American National Standard on the Control of Hazardous Energy – Lockout/Tagout And Alternative Methods (ANSI/ASSE Z244.1-2003) and requests that the Agency hyperlink from the OSHA web site to an American Society of Safety Engineers (ASSE) web page, which contains information about both the Z244 American Standards Committee (ASC) and the revised consensus standard Your letter was forwarded to our office to reply The Z244 American Standards Committee requests that OSHA provide ‘‘enhanced recognition’’ of its latest ANSI standard concerning the control of hazardous energy Your letter conveys the committee’s belief that such recognition may help prevent future injuries and 487 488 Appendix D would be consistent with provisions of the National Technology Transfer and Advancement Act (NTTAA), 15 USC x272, and the Office of Management and Budget’s Circular A-119, Federal Participation in the Development and Use of Voluntary Consensus Standards and in Conformity Assessment Activities OSHA shares your interest in preventing workplace injuries and recognizes the valuable contribution that your committee has made in developing the new Z244.1 standard In addition, OSHA is committed to working cooperatively with entities such as ANSI and ASSE to further workplace safety and health As provided below, we agree that it is prudent to reference the current American National Standard on the control of hazardous energy on OSHA’s web site Moreover, OSHA welcomes other cooperative initiatives that would assist employers and employees to further occupational safety by effectively controlling hazardous energy The OMB Circular (consistent with Section 12(d) of the NTTAA) directs agencies to use voluntary consensus standards in lieu of developing government-unique standards, except when such use would be inconsistent with law or otherwise impractical.1 Neither the NTTAA nor the OMB Circular mandate the revision of an existing standard, such as the Control of Hazardous Energy (Lockout/Tagout) (LOTO), 29 CFR x1910.147, whenever a relevant consensus standard is amended However, OSHA will consider all relevant consensus standards, including the current ANSI standard, if the Agency determines in the future that it is appropriate to revise x1910.147 Your paraphrased questions and our replies follow: Question #1: The ANSI Accredited Standards Committee formally requests that OSHA link to the [Z244 Committee] to OSHA’s [Safety and Health Topics: Control of Hazardous Energy (Lockout/Tagout) page] [Links embedded for OSHA web site posting.] Reply: OSHA believes that it is appropriate to add the ANSI Z244 Committee link and this letter to the Control of Hazardous Energy page in the Safety and Health Topics section of the OSHA web site, and we will so Question #2: OSHA references the Z244.1-1982 (R1993) standard in a number of locations on the OSHA web site The ASC’s view is that the Z244.1-2003 standard provides a level of protection superior to the earlier version and recommends that future references to the Z244.1 standard should refer to the 2003 standard Does OSHA agree with the contention that future references to the Z244.1 standard need to also include the 2003 standard? Reply: In the future, OSHA will reference the most recent version of the Z244.1 standard, whenever appropriate Thus, on the OSHA web site, the Agency will refer to the Z244.1-2003 standard when referencing consensus standards and other recognized resources that provide information and guidance concerning the control of hazardous energy However, OSHA will continue to reference the Z244.1-1982 standard when citing specific sources that the Agency considered in developing 29 CFR 1910.147, see, e.g., 54 FR 36644, 36645 (September 1, 1989) (acknowledging the role that the Z244.1-1982 standard played in the development of OSHA’s LOTO standard) Likewise, the Agency will reference only the Z244.1-1982 standard when Appendix D 489 referring to situations where OSHA explicitly considered the Z244.1-1982 standard, as opposed to the Z244.1-2003 standard, in developing a policy or practice regarding the application of the 1910.147 Question #3: What is OSHA’s enforcement position if an employer is complying with the most recent version of a voluntary consensus standard, which was either previously adopted by reference or cited as a reference document during the rulemaking process? Reply: As you know, OSHA carefully considered the 1982 ANSI standard in developing the agency’s LOTO standard, 1910.147 However, OSHA did not adopt the standard by reference, and in some respects the agency deliberately departed from the ANSI standard in order to provide a higher level of employee protection, see 58 FR 16617 (March 30, 1993) (Supplemental Statement of Reasons for the Final Rule) The OSH Act contemplates a distinction between the national consensus standard process and the process of OSHA rulemaking While the former often produces information useful in the latter, it is not equivalent Section 5(a)(2) of the OSH Act requires employers to comply with OSHA standards (29 USC x654(a)(2)) Thus, only national consensus standards that have been adopted as, or incorporated by reference into, an OSHA standard pursuant to Section of the OSH Act provide a means of compliance with Section 5(a)(2) of the OSH Act.2 While requiring employers to comply with OSHA standards, the OSH Act also authorizes OSHA to treat certain violations, which have no direct or immediate relationship to safety and health, as de minimis, requiring no penalty or abatement, see 29 USC xx 654(a)(2) and 658(a) OSHA’s enforcement policy provides that a violation may be de minimis, if an employer complies with a proposed standard or amendment or a consensus standard rather than with the standard in effect at the time of the inspection and the employer’s action clearly provides equal or greater employee protection, see OSHA Instruction CPL 2.103, Field Inspection Reference Manual, Chapter III, Paragraph C(2)(g), September 26, 1994 In applying this principle, OSHA takes heed of its rulemaking findings Question #4: We would sincerely hope that OSHA agrees with the position of the Z244 ASC that the Z244.1 standard is a viable document to use as a guideline when implementing lockout/ tagout programs Reply: OSHA recognizes the value of national consensus standards, and in many respects, the ANSI Z-244.1-2003 standard offers useful guidance for employers and employees attempting to control hazardous energy However, OSHA has not determined that, in all cases, compliance with specific provisions of the ANSI Z244.1-2003 standard and its annexes would constitute compliance with relevant OSHA requirements To a considerable extent, the OSHA LOTO standard is a performance standard, which establishes general employer obligations, but leaves employers latitude to develop and implement specific methods for meeting those obligations Where this is the case, the detailed discussion in the ANSI Z244.1-2003 standard often can assist employers in developing specific methods to meet their obligations under the OSHA LOTO standard For example, the OSHA LOTO 490 Appendix D standard establishes specific minimum criteria relevant to all energy control procedures, see 1910.147(c)(4)(ii) In Annex C, the ANSI Z244.1-2003 standard details a sample energy control procedure for a blasting cabinet and dust extractor While OSHA cannot ascertain whether the sample procedure provides the breadth and specificity mandated in 1910.147(c)(4)(ii) without more information about the actual machinery and the manner in which servicing and maintenance would be performed, this sample procedure may provide valuable conceptual assistance to an employer who is developing energy control procedures specific to its machinery/equipment as prescribed by the OSHA LOTO standard In addition, the sample LOTO placards in Annex D are good examples of supplemental tools that provide critical information specific to particular machines and equipment An employer who chooses to develop a single, generic energy control procedure can supplement its generic procedure with similar placards to comply with 1910.147(c)(4)(ii) On the other hand, in several important respects, the ANSI standard appears to sanction practices that may provide less employee protection than that provided by compliance with the relevant OSHA provisions For example, the consensus standard employs a decision matrix that allows employers to use alternative protective methods in situations where OSHA standards require the implementation of lockout/tagout or machine guarding In addition, the ANSI standard permits the use of tagout programs if they provide ‘‘effective’’ employee protection, while the OSHA LOTO standard allows the use of a tagout program only where the employer demonstrates it provides Full employee protection – i.e., a level of safety equivalent to that obtained by using a lockout program Further, the Hazardous energy control procedures, Communication and training, and Program Review sections of the ANSI standard, while detailed and conceptually valuable, not appear to mandate certain discrete practices that are prescribed in parallel sections of OSHA’s LOTO standard OSHA has not formally compared each provision of the ANSI Z244.1-2003 standard with the parallel provisions in OSHA standards Given the performance nature of both the ANSI standard and OSHA standards addressing the control of hazardous energy, the scope and purpose of OSHA letters of interpretation, and the fact-specific nature of OSHA enforcement decisions, we are not in a position to definitively state the practical effect of applying each of the various ANSI Z244.1 provisions to specific workplace conditions as you have requested In determining whether it is appropriate to issue a citation for a violation of the OSH Act, OSHA Area Directors have the discretion to apply the Agency’s de minimis policy as described above However, when an OSHA standard prescribes a practice, design, or method that provides a requisite level of employee protection, employers may not adopt an alternative approach that provides a lesser level of employee protection, see 29 USC xx654(a)(2) and 655 (respectively requiring employers to comply with occupational safety and health standards promulgated under the OSH Act and providing the Secretary of Labor with authority to promulgate, modify, or revoke OSH Act occupational safety and health standards) As you may be aware, OSHA’s Control of Hazardous Energy (Lockout/Tagout) directive (STD 1-7.3) currently is being revised; the revised directive will address the ANSI Z244.1-2003 Appendix D 491 standard to assure that OSHA personnel are familiar with the ANSI standard and conversant with the Agency’s position with respect to the application of the ANSI standard Thank you for your interest and participation in activities that further occupational safety and health OSHA is committed to working cooperatively with parties like ANSI and ASSE, who share the goal of furthering workplace health and safety We hope that this letter provides the clarification you were seeking and effectively addresses the issues that you raised OSHA requirements are set by statute, standards, and regulations Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations This letter constitutes OSHA’s interpretation of the requirements discussed Note that our enforcement guidance may be affected by changes to OSHA rules Also, from time to time we update our guidance in response to new information To keep apprised of such developments, you can consult OSHA’s website at http://www.osha.gov If you have any further questions, please feel free to contact the Office of General Industry Enforcement at (202) 693-1850 Sincerely, Richard E Fairfax, Director Directorate of Enforcement Program Notes In fact, Congress placed such a high value on consensus standards that it directed the Agency, through legislation, to utilize them in the rulemaking process Section 6(b)(8) of the Occupational Safety and Health Act of 1970 (Public Law 91-596) states: ‘‘Whenever a rule promulgated by the Secretary differs significantly from an existing national consensus standard, the Secretary shall, at the same time, publish in the Federal Register a statement of reasons why the rule as adopted will better effectuate the purposes of this Act than the national consensus standard.’’ Specific national consensus standards [e.g., American National Standards (ANSI) standards], which the Secretary of Labor adopted on May 29, 1971, were either used as a source standard and published in Part 1910 as an OSHA standard or explicitly incorporated by reference in an OSHA standard For further details see Section of the OSH Act and x1910.6 for the specific standards incorporated by reference in this part [Corrected on 1/09/2006] Source: US Department of Labor website: http://www.osha.gov/pls/oshaweb/owadisp.show_document? p_table¼INTERPRETATIONS&p_id¼24969 This page intentionally left blank Index Adjustable speed drive, 244 Affected employee, Definition, 152 Aluminum-conductor-steel reinforced (ACSR), 310, 315 American Institute of Chemical Engineers, 18 American National Standards Institute (ANSI), 5–6 United States Standards Strategy, 8–9, 61, 63, 76 American Petroleum Institute (API), 18–20 Amortisseur windings, 216 Arc flash, 183 Area classification, Class, 257–60 Division, 258–60 Material group, 261–64 Zone, 259–61 Association of Edison Illuminating Companies (AEIC), 16–18 Cable standards, 326 ASTM International, 20–2 Authority having jurisdiction (AHJ), Nationally Recognized Testing Laboratories, 101 Authorized employee, Definition, 152 LOTO, 157 Autoignition temperature, 266 Building codes, 81–82 Building Construction and Safety Code, 82 Building Officials Code Administrators International, 81 Cable, 305 Cleats, 364, 367, 369–72 Coaxial, 343 Communications, 340–3 Ethernet, 358 Instrumentation, 354–6 Circuit integrity, 354 Fire alarm, 357 Power-limited fire alarm, 358 Power-limited tray, 356 Temperature detector, 358 Tray, 357 Optical fiber, 339–40 Power and control, 310 Shielding, 308 Shielded twisted pair, 343 Supports and restraints, 364, 367, 369–72 Treeing, 320 Twisted pair, 343 Cleats, 364, 367, 369–72 Canadian Standards Association (CSA), 22–3 Endorsed standards, 23 CANENA, 23–5, 60 Capacitors Discharged, 163 Harmonics, 247 Induction motors, single phase, 220 Power, 394–402 Rotating equipment, 209 Safe work practices, 172 Circuit breaker, 129 Circuits, Intrinsically safe, 278–79 Nonincendive, 279 Circular mil, 305 Classified area equipment, 69 Clearances and approach distances, 195–6 Combination motor controller, 242 Compliance audit, 193–4 Confined work spaces, 198 493 494 Index Contactors, 63–7 Contract Work Hours and Safety Standards Act, 145 Department of Energy (DOE), 172–8 Distribution transformer efficiency, 379–81 Distributed energy resources, 409–15 Distribution transformer Definition, 174 Efficiency, 379–81 Dust-ignition-proof enclosure, 291 Dusttight enclosure, 291, 293 Encapsulation, 279, 284 Enclosures, Dust-ignition proof, 291 Dusttight, 291, 293 Explosion-proof, 277 Flameproof, 285, 287 Purged and pressurized, 278 Electrical shock, 183–4 Electric Power Research Institute (EPRI), 326, 420, 425 Electroendosmosis, 309 Enclosed space, 168 Encapsulation, 279, 284 Energy control Outside personnel and contractors, 165–6 Program, 153–4 Annual periodic inspection, 156–7 Procedures, 154–5 Energy Isolation Isolating device, 151 Employee notification, 161 Energy Policy and Conservation Act, 173–4 Engineering judgment, Equipment enclosures, 70–74 Equipment protection systems, 69 Explosion-proof enclosure, 277 Explosive limits, Lower, 266 Upper, 266 Faraday’s Law, 217 Federal Emergency Regulatory Commission (FERC), 418–20, 467 Fire watch, 192–3 Flameproof enclosure, 285, 287 FM Global, 31–2 Fuel cells, 409, 410, 412 Generators, DC, 218 Induction, 216 Synchronous, 217 Glowing contacts, 205 Ground fault protection device, 131 Ground grid, 464, 466 Harmonization, 45, 55 ANSI, 61 Classified area equipment, 69 CANENA, 23–5 NEMA, 38 Standards, 62 UL, 45 Harmonic mitigation, 249–53 Hazardous energy control, 147–55, 473 Hermetically sealed, 293 IEC/IEE joint agreement, 12 Illuminating Engineering Society of North America (IESNA), 25 Increased safety, 287, 289–90 See Type of protection, 290 Index of cooling (IC), 213 Index of protection (IP), 213 Institute of Electrical and Electronic Engineers (IEEE), 32–4 IEC Agreement, 62–3 Instrumentation, Systems, and Automation Society (ISA), 26–30 standards development, 28–30 Insulated Cable Engineers Association, Inc (ICEA), 34–5, 329 Insulation Treeing, 320 International Code Council, 81–2 International Electrotechnical Commission (IEC), industry technical agreements, 11 international standard, 10–11 publically available specification, 11 Index technical specifications, 11 technology trend assessment, 12 International Organization for Standardization (ISO), 6, 9, 12 correspondent member, 13 experts on national delegations, 13 international standards, 14–6 liaison status, 13 member bodies, 12–13 national mirror committees, 13 NEMA, 38 technical committees, 14 subscriber members, 13 International Telecommunication Union, 55 Intrinsically safe, 278–9 Leakage distance, 437 Life Safety CodeÒ, 86–7, 110–12 Line insulators, 433, 437 Lockout (LO), 194–5 Definitions, 152 Devices, 155–6 Comparison of CFR 1910 LOTO standards, 473–86 Release, 164 Maximum experimental safe gap, 261–63 Metal-enclosed power switchgear, 132 MIL, 305 Minimum approach distance, 169, 196 Minimum igniting current ratio, 261–63 Minimum lighting levels, 193 Motor (Electric), Control, 221, 229, 237–40 Adjustable speed drive, 244 DC, Compound-wound, 218 Differential, 218 Permanent magnet, 218 Series-wound, 217 Shunt-wound, 217 Design letters, 219 Induction, 216 Single-phase, 219–20 Synchronous, 216 495 Motor enclosures, Open machine, 213 Totally enclosed machine, 214 NACE International, 36–8 National consensus standard, 144 National Electrical CodeÒ, 2–3, 42, 79, 83, 112 Building Construction and Safety Code, 82 Cables, 322 Electrical hazardous area, 257 Equipment markings, 293 Intrinsically safe, 278 Reactors, 385 Transformers, 376 National Electrical Manufacturers Association (NEMA), 38–41 National Electrical Safety CodeÒ (NESC), 74, 145, 169, 171–2, 189, 340, 427, 448, 465 National Fire Protection Association (NEPA), 41–4 Nationally Recognized Testing Laboratories, 89, 101–7 North American Electric Reliability Corporation (NERC), 420 Occupational Safety and Health Standards, 47, 91, 96, 104, 143–4 Occupational Safety and Health Administration (OSHA), 46–9 Nationally Recognized Testing Laboratories, 101–6 Oil immersion, 290–91 Open-consensus document, Operating overload condition, 238 Optical fiber cables, 339–40 Overload relay, 240–42 Personal protection equipment (PPE), 136–8 Polarization index (PI), 339 Photovoltaic, 410–12 Powder fillings, 290 Qualified person, 189 Qualified personnel, 149, 152–3 Raceway, 359 Reactors, 385 Recommended practice, 496 Index Rotors, Wound, 216 Squirrel-cage, 216 Safe work permits, 185–7 Service equipment, 116 Service point, 116 Short-circuit interrupting rating, 243 Southern Building Code Congress International, 81 Standard, 3–4 consensus, 11 international, 10 Standards development organization (SDO), Static electricity generation, 192 Surge arresters, 437, 439, 443, 446 Switchboard, 132 Switchgear, 462–63 Tagout (TO) Comparison of CFR 1910 standards, 473–86 Definition, 152 System, 160 Release, 164 Thermal overload relays, 68 Total harmonic distortion (THD), 249 Transformers, 134, 375–385 Ideal, 375 Substation, 377 Tests, 381–5 Distribution, efficiency, 379–81 Transmission and distribution, 405, 426–30 National consensus standards, 145 United States Standards Strategy, 8–9, 61, 63, 76 Unit substation, 461 Underwriters Laboratories (UL), Inc., 44–6 Unqualified personnel, 149 Utility poles, Concrete, 433 Fiber-reinforced polymer, 433 Steel, 433 Wood, 427, 429–30, 432 Welding accidents, 199–202 Wind turbines, 410, 412 Wire, 305 Wood preservatives, 431–32 Wood poles, 427–28, 431–33 Work on energized equipment, 195 ... J Electrical codes, standards, recommended practices and regulations: an examination of relevant safety considerations Electrical engineering? ?Safety measures Electrical engineering? ?Safety regulations. .. documents Electrical generation, transmission, and distribution codes, standards, and recommended practices encompasses a large area of information Some general codes, standards, and recommended practices. .. have adopted ISO and IEC standards The growth of the use of ISO and IEC standards has challenged US competitiveness The electrical engineering codes, standards, and recommended practices examined