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Electrical Standard; Clarifications; Corrections

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Occupational Safety and Health Administration, Labor.


Final rule; clarifications; correcting amendments.


The Occupational Safety and Health Administration (OSHA) Start Printed Page 64203published a final rule revising its electrical installation standard for general industry on February 14, 2007. This notice clarifies the scope of one provision in the final standard and addresses some questions raised by stakeholders on the application of the provision. This also corrects two typographical errors located elsewhere in the final rule.


The corrections become effective on October 29, 2008.

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Mr. David Wallis, Directorate of Standards and Guidance, Room N-3609, OSHA, U.S. Department of Labor, 200 Constitution Avenue, NW., Washington, DC 20210; telephone (202) 693-2222.

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On February 14, 2007, OSHA published a revision of its electrical installation standard for general industry found in 29 CFR part 1910, subpart S (72 FR 7136). This final rule went into effect on August 13, 2007. Since the final rule was promulgated, the Agency has received some questions from the public regarding one provision, 29 CFR 1910.304(b)(3)(ii). At its meeting on August 1, 2007, in Oakland, CA, the Maritime Advisory Committee on Occupational Safety and Health (MACOSH) discussed the provision and several MACOSH members were uncertain about the extent of the application of this provision to shipyard employment and had questions on how the Agency would interpret the rule. Consequently, MACOSH recommended that the Agency use the best available means to assist employers in complying with the requirements of the provision and that the Agency delay the effective date of § 1910.304(b)(3)(ii) for a period of 6 months or until the Agency can clarify the standard.

In this notice, OSHA addresses these questions and makes one change to the regulatory text of the provision in order to clarify OSHA's intent regarding its scope. This change does not alter the substantive obligations of affected parties. Additionally, OSHA is correcting two typographical errors located in Table S-3 of the final rule.


1. What is the application of § 1910.304(b)(3)(ii)?

As originally published, the introductory text to § 1910.304(b)(3)(ii) read as follows:

The following requirements apply to temporary wiring installations that are used during maintenance, remodeling, or repair of buildings, structures, or equipment or during similar construction-like activities.

A few members of MACOSH and two other individuals have raised questions regarding the meaning of this provision. Some of the questions stem from the structure of the text of the provision, which OSHA is changing in this notice to better match the Agency's intent. Other questions relate to the meaning of the terms “construction-like” activities and “temporary wiring installations.”

a. Structure of the Regulatory Text

Paragraph (b)(3)(ii) was taken from Section 2-2.4.2 of the 2000 edition of NFPA 70E, which reads, in relevant part, as follows:

2-2.4.2 Ground-Fault Protection for Personnel. Ground-fault protection for personnel for all temporary wiring installations shall be provided to comply with 2- or 2- below. This section shall apply only to temporary wiring installations used to supply temporary power to equipment used by personnel during construction, remodeling, maintenance, repair, or demolition of buildings, structures, equipment or similar activities.

Both OSHA's final rule and NFPA 70E are intended to apply to temporary wiring installations used during the performance of construction-like activities. From questions the Agency has received about this provision, the intent of the rule may not be readily apparent from the text. Because part 1910 does not apply to construction, the Agency removed “construction” from the list of activities specifically mentioned in NFPA 70E and changed “similar activities” to “similar construction-like activities.” OSHA did not, however, intend to deviate from the underlying intent of the NFPA 70E provision, which was to limit its application to activities that were construction-like in nature. The Agency is concerned that the regulatory text of § 1910.304(b)(3)(ii) may be read to include activities that are not construction-like. To clarify the Agency's intent, OSHA is revising the introductory text to § 1910.304(b)(3)(ii) to read:

The following requirements apply to temporary wiring installations that are used during construction-like activities, including certain maintenance, remodeling, or repair activities, involving buildings, structures or equipment. [Emphasis added.]

This change makes it clear that § 1910.304(b)(3)(ii) applies only to such activities.

b. Construction-Like Activities

When determining whether the provisions of § 1910.304(b)(3)(ii) apply, employers must determine whether a particular activity is “construction-like” in nature. The preamble to the final rule provided examples of what OSHA considers “construction-like activities” in the discussion of § 1910.305(a)(2)(iii) related to the use of temporary wiring over 600 volts (72 FR 7163).

It should be noted that the discussion of the term “construction-like activities” here and in the preamble to OSHA's final rule applies only to the use of this term in subpart S. It should also be noted that not all maintenance, remodeling, or repair work is construction-like.

Construction-like activities fall into two general categories: Activities that would be covered under OSHA's construction standards but for the fact that they are specifically covered by other OSHA standards, and all other activities that do not qualify as construction but involve electrical hazards similar to those typically found in construction work.

The vast majority of activities covered under subpart S are in the first category. For example, ship building and ship repair would be considered to meet the definition of “construction” because of their scale and complexity; nevertheless, the hazards associated with this work are specifically covered by OSHA's shipyard employment standards. However, the shipyard standards do not protect employees from all of the hazards addressed by paragraph (b)(3)(ii) of § 1910.304; in such instances, this paragraph applies to hazards not covered by the shipyard standards, as outlined in § 1910.5(c). (The application of subpart S to shipyard employment is discussed in more detail in the preamble to the final rule, 72 FR 7141.)

The remaining activities intended to be covered under subpart S fall into the second category of construction-like activities. This category includes certain “maintenance, remodeling, or repair activities involving buildings, structures, or equipment” that pose electrical hazards similar to those typically found in construction work. In this respect, OSHA intends the term “construction-like” to apply to activities that, while not construction, involve some of the hazards that are typically found in construction work. In general, these are activities that pose hazards that are similar to those associated with the use of temporary receptacles on construction sites—that is, hazards resulting from more severe use or environmental conditions. Examples of such activities include: Damage to a cord set [1] from rough use; exposure to Start Printed Page 64204wet, damp, or conductive conditions, such as often encountered when working outside; and frequent reconfiguration and rearrangement of the electric equipment.

Some examples of this type of construction-like activity were given in the preamble to the final rule, including clean up and disaster remediation. To illustrate, if a storm blew over a tree on a factory's premises and temporary wiring was employed to power a chainsaw and other clean-up equipment, such remediation activity would be construction-like.

Other examples of construction-like activities follow.

Example A: Employees are engaged in a minor building repair using temporary wiring. The conditions are damp or an electric cord set is being used and is subjected to rough use or abuse.

Example B: Manufacturing prefabricated housing, in which houses or portions of houses are assembled in a manufacturing plant. This process poses some electrical hazards that are similar to those found during housing construction (for example, rough use of cord sets).

Example C: Performing heat exchanger tubing water-blasting (hydro-cleaning) using temporary wiring. This process is usually done outside in wet and conductive environmental conditions and may involve rough cord use.

Maintenance activities that do not involve electrical hazards similar to those found in construction are not “construction-like,” and therefore are not subject to § 1910.304(b)(3)(ii). Building maintenance activities such as floor polishing and vacuuming and drilling holes to hang pictures on walls, would be some common examples of such activities.

Activities that are large in scale, complex, or require significant time, materials, and tools to complete typically would be considered actual construction work instead of construction-like.[2] As such, these activities would be subject to the construction standards instead of subpart S. To illustrate, the stripping and repainting of a bridge would not be subject to subpart S, because it would be considered construction.

c. Temporary Wiring

In addition, paragraph (b)(3)(ii) applies only to temporary wiring installations. OSHA does not consider a single extension cord set connected to a permanent receptacle outlet to be a temporary wiring installation.[3] In such situations, extension cords are typically used to extend the length of the power supply cord on a tool or appliance to reach a nearby receptacle outlet. In this application, OSHA considers the extension cord set to be part of the utilization equipment.

Paragraph (a)(2)(v)(A) of § 1910.305 requires temporary wiring branch circuits to originate in an approved power outlet or panelboard. Normally, this is done through a portable distribution board, portable power outlet, or similar equipment. All the wiring extending from the portable power outlet or panelboard would be considered temporary wiring. However, in a permanent facility, it may be possible to run a series of cord sets from permanent outlets as a means of supplying power on a temporary basis. Although the NEC and NFPA make no clear distinction between temporary wiring and the use of extension cord sets, under certain conditions, the use of multiple cord sets would constitute a temporary wiring installation. A series of extension cord sets run from a single permanent outlet would constitute temporary wiring though such an installation would not strictly comply with the requirements relating to the origin of temporary branch circuits. Similarly, running a long extension cord set from a permanent outlet to power more than one piece of electric equipment would result in a temporary wiring installation.

Thus, for the purposes of § 1910.304(b)(3)(ii), OSHA will consider as “temporary wiring” the use of more than one extension cord (connected in series or otherwise) to a permanent outlet, or the temporary connection of more than one piece of utilization equipment to an extension cord set that is connected to a permanent receptacle outlet.[4]

OSHA notes, however, that this temporary wiring would only be covered by § 1910.304(b)(3)(ii) if it is used during “construction-like activities.”

2. Does § 1910.304(b)(3)(ii) apply to all receptacles or only those on branch circuits?

Paragraph (b) of § 1910.304 applies only to branch circuits. The definition of “branch circuit” is “[t]he circuit conductors between the final overcurrent device protecting the circuit and the outlets.” The definition of “outlet” is “[a] point on the wiring system at which current is taken to supply utilization equipment.” Thus, the branch circuit extends from the final overcurrent device to points on the circuit where power is taken to supply utilization equipment (for example, an electric tool). Receptacles that are used to power downstream cord-connected overcurrent devices for additional circuits are not covered because they are not part of the branch circuit. For example, receptacles on a spider box that supply downstream spider boxes with overcurrent-protected circuits would not be covered by § 1910.304(b)(3)(ii). A spider box is a portable power outlet unit used with temporary wiring installations. The box, which is typically fed by a 125/250-volt, 50-ampere cord set, contains overcurrent protection for 125- or 250-volt, 15-, 20-, or 30-ampere receptacle outlets [5] and frequently contains a pass-through 50-ampere outlet for downstream spider boxes. The 50-ampere receptacle outlets are not receptacle outlets when they supply downstream spider boxes. They are receptacle outlets when they supply 50-ampere electric utilization equipment directly.

3. Does the standard recognize all forms of ground-fault protection devices or only ground-fault circuit interrupters approved by nationally recognized testing laboratories (NRTL)?

The standard requires ground-fault circuit interrupters for personnel protection in § 1910.304(b)(3)(ii)(A). As electric equipment, these GFCIs must be NRTL approved.[6] These devices have trip levels of approximately 5 milliamperes and trip in as little as 0.025 seconds. Devices such as ground-Start Printed Page 64205fault protection for equipment, earth-leakage detectors, and similar equipment are not acceptable substitutes. These devices, which may also be NRTL approved, interrupt the circuit at higher trip levels and, in some cases, do not function to trip the circuit automatically at all.

4. Does the standard require GFCIs to be used with branch circuits supplying temporary lighting?

The standard requires GFCI protection for temporary circuits supplying lighting only when those circuits also supply receptacles. Employers are not required by the standard to install GFCIs for lighting if the design of the temporary lighting is such that the circuits do not also supply receptacles.[7]

Exemptions From Notice and Comment and Delay in Effective Date

Under the Administrative Procedure Act (APA), an agency may make a “good cause” finding that notice and comment rulemaking procedures would be impracticable, unnecessary, or contrary to the public interest. 5 U.S.C. 553(b)(B); see also 26 CFR 1911.5 (permitting OSHA to promulgate minor changes or amendments to standards without notice and comment when the changes are accompanied by a statement of good cause for the absence of notice and comment). An agency may similarly make the rule effective upon publication when it determines that delaying the effective date of the rule, as normally required by 5 U.S.C. 553, is unnecessary and good cause exists to make the rule effective immediately. 5 U.S.C. 553(d)(3).

In this instance, OSHA finds that good cause exists under 5 U.S.C. 553(b)(B) and (d)(3) to forego public notice and comment for these minor amendments and to make them effective immediately upon publication in the Federal Register. Notice and comment procedures for the amendments herein, as well as a delay in the effective date of the amendments, are unnecessary because the amendments are minor clarifications and typographical corrections that do not affect the substantive requirements or coverage of the standards involved, modify or revoke existing rights and obligations, or establish new rights and obligations. Moreover, the clarifications respond to requests for immediate formal guidance to assist employers in complying with the existing standards.

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List of Subjects in 29 CFR Part 1910

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This document was prepared under the direction of Edwin G. Foulke, Jr., Assistant Secretary of Labor for Occupational Safety and Health, 200 Constitution Avenue, NW., Washington, DC 20210.

This action is taken pursuant to sections 4, 6, and 8 of the Occupational Safety and Health Act of 1970 (29 U.S.C. 653, 655, 657), Secretary of Labor's Order No. 5-2007 (72 FR 31160), and 29 CFR Part 1911.

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Signed at Washington, DC, this 24th day of October 2008.

Edwin G. Foulke, Jr.,

Assistant Secretary of Labor for Occupational Safety and Health.

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Part 1910 of Title 29 of the Code of Federal Regulations is amended as follows:

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Subpart S—[Amended]

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1. The authority citation for subpart S is revised to read as follows:

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Authority: Secs. 4, 6, 8, Occupational Safety and Health Act of 1970 (29 U.S.C. 653, 655, 657); Secretary of Labor's Order No. 8-76 (41 FR 25059), 1-90 (55 FR 9033), 5-2002 (67 FR 65008), 5-2007 (72 FR 31160), as applicable; 29 CFR part 1911.

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2. Amend Table S-3 by correcting “2.81” and “9.01,” the first entries under the column heads “m” and “ft,” to read “2.8” and “9.0,” respectively.

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3. Revise the introductory text to § 1910.304(b)(3)(ii) to read as follows:

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Wiring design and protection.
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(b) * * *

(3) * * *

(ii) The following requirements apply to temporary wiring installations that are used during construction-like activities, including certain maintenance, remodeling, or repair activities, involving buildings, structures or equipment.

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1.  A cord set is commonly known as an extension cord.

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2.  Note that confined space activities specified in OSHA Directive CPL 02-00-100, Application of the Permit-Required Confined Spaces (PRCS) Standard, 29 CFR 1910.146, are covered by the general industry confined space standard. Appendix E, Question 8, of that directive gives examples of activities covered by the general industry confined space standard that may be considered construction-like.

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3.  It should be noted that the language in the GFCI provision in the construction standards is not the same as the language in subpart S. The construction standard (§ 1926.404(b)(1)) applies its GFCI criteria to receptacle outlets that are not a part of the permanent wiring without regard to whether they are used with a temporary wiring installation. Thus, under the construction standard, a GFCI is required for an extension cord set plugged into a permanent 120-volt, 15- or 20-ampere receptacle outlet unless the employer is using an assured equipment grounding conductor program.

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4.  This interpretation does not apply to the connection of multiple pieces of electric equipment to an approved relocatable power taps used in accordance with its listing or labeling.

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5.  Spider boxes are typically manufactured with built-in GFCI protection for these receptacles.

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6.  Paragraph (a) of § 1910.303 requires all electric equipment to be approved. Under the definitions of “approved” and “acceptable,” this generally requires approval by an NRTL.

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7.  OSHA notes that Section 590.4(D) of the 2005 National Electrical Code (NEC) prohibits the installation of receptacles on branch circuits that supply temporary lighting for construction sites. This requirement is intended to ensure that temporary lighting is not subject to tripping by the GFCIs required on construction sites. Subpart S does not contain a similar prohibition.

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[FR Doc. E8-25789 Filed 10-28-08; 8:45 am]