Appendix E Application of the National Electrical Safety Code Grandfather Clause

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1 National Electrical Safety Code Handbook, Sixth Edition Edited by Allen L. Clapp Copyright 2006 The Institute of Electrical and Electronics Engineers, Inc. Appendix E Application of the National Electrical Safety Code Grandfather Clause 1. Discussion The early editions of the NESC each required that all existing facilities either be brought into compliance with the new edition or guarded, unless the administrative authority said it wasn't worth the cost of doing so. This was contained in Rule 101 for Electric Supply Stations and Rule 201 for Overhead (including the limited rules for underground risers). The last edition of the NESC containing these requirements for electric supply stations was the 5th Edition of For overhead and underground it was the 6th Edition of See the code language for these editions shown below. The first editions to add the so-called grandfather clause to allow existing facilities to remain in compliance with the edition that previously applied (instead of the new edition) were the 1971 revision of Rule 101 of Part 1 (Stations), the 1973 codification of new Rule 302 in new Part 3 (Underground) and the 1977 revision of Rule 202 in Part 2 (Overhead). See the applicable language of these editions shown below As a result of these changes, an existing installation can now stay in compliance with the previously applicable edition after a new edition is issued. However, even if an overhead or underground line was originally constructed under the 5th Edition, the oldest edition that could be applicable is the 6th Edition of Part 2, because that edition required existing facilities to be brought into compliance with it or guarded. Similarly, for power plants and substations installed before 1941, the 5th Edition of Part 1 is the earliest that could apply. The 1981 Edition was the first modern edition in which all Parts of the NESC were revised at the same time. As a part ofthat revision, the scope, application and definition rules were moved from the individual Parts of the code to a new Section 1 that applied to the entire code. 670 NESC Handbook 6th Edition

2 The application rules were contained in new Rule 013, as shown below. Rule 013 was clarified in the 1990 and 2002 editions. Rules 013B2 and 013B3 form the limitations and application of the grandfather clause. Under Rule 013B2, an existing facility (including maintenance replacements) is not required to change when a code requirement changes, but it is allowed to be changed under Rule 013B1 to meet the new edition. The basic mechanism for applying code editions falls under the application of Rule 013B3. If an existing installation has either (1) its structure replaced for maintenance purposes, (2) an item on the structure replaced, (3) an item added to the structure, or (4) items on the structure altered (such as relocating items to accommodate required clearance to a new item), the resulting installation must meet either (1) the present edition of the NESC or (2) the edition that was previously applicable. The previously applicable edition may be either (1) the edition applicable at the time of original construction (for electric supply stations constructed after 1941 and overhead or underground lines constructed after 1961) or (2) a subsequent edition with which it is in compliance. As a practical matter, utilities seldom have older construction standards available while working on structures or inspecting structures. Construction standards are typically updated as each new code edition becomes effective. When they inspect after working on an installation, the inspection is usually done with the current utility standards. Further, most of the older installations meet the requirements of modern editions of the code. As a result, most installations are generally in compliance with current standards as they change from time to time, unless there are major difficulties in meeting new code requirements. If existing facilities meeting one code edition are brought into compliance with a later edition, it is not intended that an earlier edition be reapplied at a later time. Significant problems can occur with some older installations because of new additions to the installation. Later codes allow many things to NESC Handbook 6th Edition 671

3 occur that were not allowed or specified by earlier editions. If someone installs something in or on an older facility in a manner that is routinely done by today's standards, but not allowed by the earlier standard, the installation no longer complies with the earlier standard. Thus, a new addition to an existing installation could result in taking the existing installation out of compliance with the grandfathered edition if care is not taken to assure that new additions are only made in compliance with the restrictions of the grandfathered edition. In such a case, the edition that is current at the time of the addition would be required of the resulting installation. Example 1: Consider that, prior to the 1990 Edition, the NESC required a supply cable conduit installed down a pole to be covered by a nonmetallic covering where it runs through the communication space. The 1987 and prior editions did not allow the later option of bonding the grounded cable messenger to the grounded conduit, instead of covering the conduit with a nonmetallic covering. Scenario 1A: Consider an overhead line power line that currently meets the 6th Edition and needs to remain in compliance with that edition to meet building clearance requirements. One of the poles has a primary underground riser running up the pole. The cables are protected by a galvanized steel conduit. No communication cables are attached. If a communication utility with a joint-use agreement were to attach a cable to the pole and bond the grounded cable messenger to the metal riser conduit, as is allowed by current code, the installation would no longer meet the 6th Edition. Scenario IB: Consider an overhead joint-use line with existing power and communication cables. If the power utility added a metallic conduit down the pole and bonded it to the cable messengers, that would take the installation out of compliance with the 6th Edition. Unless older facilities that are intended to be kept in compliance with an earlier edition are identified in some fashion, and unless the employees know how to keep the facility in compliance with the earlier edition, the result may be noncompliance with the code. Further, when an older edition does not specify a particular requirement, but a new edition does specify a requirement, the requirement specified in the current edition must be met if changes occur, in order to comply with the previous edition. This is because Rule 012C requires accepted good practice for given local conditions for all particulars not specified in the code. The current edition specifies good practice. 672 NESC Handbook 6th Edition

4 Example 2: A lake is constructed under an existing power line that was installed and is being maintained under the 6th Edition. The first accidents involving the relatively new high-masted catamaran sailboats occurred in 1969 and The 6th Edition did not contain specifications for clearances above water. The first edition to do so was the 1977 Edition. If sailboat clearances had been addressed by the utility for lines above water before the 1977 Edition was published, and (1) the line cleared the water by enough to clear the masts of the expected sailboats, but (2) not by the full amount of the new code requirement, the line would still be in compliance with the 6th Edition, since the line would clear the expected sailboat and, thus, meet good practice at the time. The NESC specified accepted good practice for sailboat clearances over water for the first time in Thus, if (1) the line was built before the 1977 Edition and application of the 6th Edition of the NESC was desired to be maintained, and (2) the lake was built after the 1977 Edition specified clearances above water, the NESC water clearances in effect at the time of the post-1977 lake construction under the line (1977 or later, as applicable) would have to be met, in order to meet the good practice rule of the 6th Edition. Notwithstanding the above, if the US Army Corps of Engineers administers an over-water clearance requirement above the lake, that requirement may exceed the NESC clearances and would be specified in the permit. The Corps first adopted the NESC in The following excerpts show how the NESC rules have changed. Emphasis has been added. 2. Language of NESC Requirements NESC 5th Edition; NBS Handbook No. 31, issued 8 May 1940, Approved ASA 8 May 1941 Part 1. Electric Supply Stations RULE 101. APPLICATION OF THE RULES AND EXEMPTIONS A. Application and Waiving of Rules The rules are intended to apply to all installations, except as modified or waived by the proper administrative authority or its authorized agents. They are intended to be so modified or waived in particular cases wherever any rules are shown for any reason to be impractica- NESC Handbook 6th Edition 673

5 ble such as by involving expense no justified by the protection secured; provided equivalent or safer construction is secured in other ways, including special working methods. Other methods of construction and installation than those specified in the rules may also be made as experiments to obtain information, if done where supervision can be given by the proper administrative authority. B. Intent of Rules The intent of these rules which constitute a minimum standard will be realized: 1. By applying the rules in full to all new installations, reconstructions, and extensions. 2. By altering existing installations as needed in a manner approved by administrative authority. 3. The time allowed for bringing existing installations into compliance with the rules will be determined by the administrative authority NESC 6th Edition, ASA C , NBS Handbook 80, issued 1 November 1961 Part 2. Overhead Electric Supply and Communication Lines Editors Note: Part 2 included requirements for underground risers in Section 29 in this and previous editions. RULE 201. APPLICATION OF THE RULES AND EXEMPTIONS. A. Intent, Modification The rules shall apply to all installations except as modified or waived by the proper administrative authority. They are intended to be so modified or waived whenever they involve expense not justified by the protection secured or for any other reasons are impracticable; or whenever equivalent or safer construction can be more readily provided in other ways. 674 NESC Handbook 6th Edition

6 B. Realization of Intent The intent of the rules will be realized: 1. By applying the rules in full to all new installations, reconstructions, and extensions, except where for special reasons any rule is shown to be impracticable or where the advantage of uniformity with existing construction is greater than the advantage of construction in conformity with the rules. 2. By placing guards on existing installations or otherwise bringing them into compliance with the rules, except where the expense involved is not justifiable. NOTE: The time allowed for bringing existing installations into compliance with the rules as specified in 2 will be determined by the proper administrative authority. NESC 6th Edition, ANSI C , NBS Handbook 110-1, issued June 1972 Part 1. Electric Supply Stations RULE 102. APPLICATION OF THE RULES AND EXEMPTIONS APPROVED BY ANSI 14 JULY 1971 A. Application The rules shall apply to all installations except that they may be modified or waived by the proper administrative authority when shown to the impracticable. In such cases, equivalent or safer construction shall be secured in other ways, including special working methods. Methods of construction and installation other than those specified in the rules may also be made as experiments to obtain information, if done where proper supervision can be administered. B. Intent of Rules The intent of these rules, which constitute a minimum standard, will be realized by applying the rules in full to all new installations, alterations, reconstructions, and extensions. Rules in this Code which are to be regarded as mandatory are characterized by the use of the word "shall." Where a rule is of an advisory nature, it is indicated by the use of the word "should." Other practices which are considered NESC Handbook 6th Edition 675

7 desirable but not intended to be mandatory are stated as recommendations. It is realized that conditions may exist which necessitate departures from such recommendations. Notes contained herein are for information purposes only and are not to be considered as mandatory or as part of the Code requirements. Editor's Note: By removing the requirement to guard existing facilities meeting the previous edition that do not also meet the new edition, the grandfather clause was effectively created NESC ANSI C issued 20 July 1973 Part 3. Underground Electric Supply and Communication Lines 302 INTENT AND APPLICATION OF RULES B. New Installations, Reconstruction, and Extensions These rules shall apply to all new installations, reconstructions, and extensions except that they may be waived or modified by the proper administrative authority when shown to be impractical. In such cases, equivalent or greater safety shall be secured in other ways including special working methods. Methods of construction and installation other than those C. Existing Installations These rules do not apply to existing installations except as may be required for safety reasons by the proper administrative authority NESC ANSI C issued 28 February INTENT AND APPLICATION OF RULES B. Application of Rules 1. New Installations, Reconstructions, and Extensions These rules shall apply to all new installations, reconstructions, and extensions except where they may be waived or modified by the proper administrative authority when shown to be impractical or when equivalent of safer construction can be more readily provided in other ways. Methods of construction and installation other than those specified in the rules may be used experimentally to obtain information if done where proper supervision is provided. 676 NESC Handbook 6th Edition

8 2. Existing Installations Existing installations, including maintenance replacements, which comply with prior editions of this code need not be modified to comply with these rules except as may be required for safety reasons by the proper administrative authority. A replacement for a supporting structure, however, shall conform to the current edition ofrule238c. Editor's Note: This was the first edition to state the intended requirement that any existing installation not meeting the new edition must meet the previously applicable edition. Starting with the 1981 Edition, an effective date of 180 days after publication was specified. A new edition may be used upon issuance NESC, ANSI C issued 5 September 1980 RULE 013. APPLICATION Editors Note: This rule is unchanged in 1984 and 1987 Editions and applies to all Parts of the NESC A.New Installations and Extensions 1. These rules shall apply to all new installations and extensions, except that they may be waived or modified by the administrative authority. When so waived or modified, equivalent safety shall be provided in other ways, including special work methods. 2. Types of construction and methods of installation other than those specified in the rules may be used experimentally to obtain information, if done where qualified supervision is provided. B. Existing Installations 1. Existing installations including maintenance replacements, which comply with prior editions of the code, need not be modified to comply with these rules except as may be required for safety reasons by the administrative authority. 2. Where conductors or equipment are added, altered, or replaced on an existing structure, the structure or the facilities on the structure need not be modified or replaced if the resulting installation will be in compliance with the rules which were in effect at the time of the original installation. NESC Handbook 6th Edition 677

9 1990 NESC, ANSI C issued 1 August 1989 Rule 013. APPLICATION Editor's Note: This rule is unchanged in 1993 and 1997 Editions. A.New Installations and Extensions 1. These rules shall apply to all new installations and extensions, except that they may be waived or modified by the administrative authority. When so waived or modified, equivalent safety shall be provided in other ways, including special work methods. 2. Types of construction and methods of installation other than those specified in the rules may be used experimentally to obtain information, if done where qualified supervision is provided. B. Existing Installations 1. Where an existing installation meets, or is altered to meet, these rules, such installation is considered to be in compliance with this edition and is not required to comply with any previous edition. 2. Existing installations including maintenance replacements, which comply with prior editions of the code, need not be modified to comply with these rules except as may be required for safety reasons by the administrative authority. 3. Where conductors or equipment are added, altered, or replaced on an existing structure, the structure or the facilities on the structure need not be modified or replaced if the resulting installation will be in compliance with either (1) the rules which were in effect at the time of the original installation, or (2) the rules in effect in a subsequent edition to which the installation has been previously brought into compliance, or (3) the rules of this edition in accordance with Rule 013B NESC, ANSI C issued 1 August 2001 RULE 013. APPLICATION A.New Installations and Extensions 1. These rules shall apply to all new installations and extensions, except that they may be waived or modified by the administrative authority. When so waived or modified, equivalent safety shall be provided in other ways. 678 NESC Handbook 6th Edition

10 EXAMPLE: Alternative working methods, such as the use of barricades, guards, or other electrical protective equipment, may be implemented along with appropriate alternative working clearances as a means of providing safety when working near energized conductors. 2. Types of construction and methods of installation other than those specified in the rules may be used experimentally to obtain information, if done where a. Qualified supervision is provided b. Equivalent safety is provided, and c. On joint-use facilities, all affected parties agree. B. Existing Installations 1. Where an existing installation meets, or is altered to meet, these rules, such installation is considered to be in compliance with this edition and is not required to comply with any previous edition. 2. Existing installations including maintenance replacements, which comply with prior editions of the code, need not be modified to comply with these rules except as may be required for safety reasons by the administrative authority. 3. Where conductors or equipment are added, altered, or replaced on an existing structure, the structure or the facilities on the structure need not be modified or replaced if the resulting installation will be in compliance with either (1) the rules which were in effect at the time of the original installation, or (2) the rules in effect in a subsequent edition to which the installation has been previously brought into compliance, or (3) the rules of this edition in accordance with Rule 013B1. NESC Handbook 6th Edition 679