Installation and equipment approvals are what we strive for on a  project. Approval processes can be straightforward or involve multiple steps, many of which are related to communication and relationships with inspectors. The authority having jurisdiction (AHJ) has significant responsibilities relative to approvals. This article reviews some of the challenges in achieving approvals for electrical system installation and equipment, including special or one-of-a kind equipment or systems.

Article 90 of the National Electrical Code provides information related to its scope, how the NEC is arranged, how it is intended to be applied and enforced, how units of measurement are indicated, wiring and planning, examination for safety, and so forth. Sections 90.2, 90.4 and 90.7 include important provisions related specifically to installation and equipment inspection approvals.

First, some definitions

Section 90.2(F) indicates that special permission can be granted during the approval process. The AHJ does not often use this, but it is essential when dealing with situations that involve unique installations, equipment, methods or procedures that the current edition does not address. Special permission from the AHJ must be in writing.

Contractors and inspectors must develop a thorough understanding of Section 90.4, Enforcement. The AHJ has significant responsibilities according to this section. First, the inspector must interpret the minimum requirements of the code and apply them to electrical installations, equipment and systems. The second responsibility is deciding on equipment and material approvals, and the third is related to situations where special permission could be granted. 

Definitions are essential in applying any code or standard. There are key definitions in play specific to AHJ approvals. The first is the definition of the word “approved,” which is defined in Article 100 as “acceptable to the authority having jurisdiction.” 

The term “authority having jurisdiction” is defined as “an organization, office, or individual responsible for enforcing the requirements of a code or standard, or for approving equipment, materials, an installation, or a procedure.”

Equipment testing

Section 90.7, Examination of Equipment for Safety, indicates that equipment that is tested, evaluated and certified to applicable standards under controlled conditions by facilities properly equipped to do so avoids the necessity for repetition of the same examinations or evaluations. The equipment typically bears appropriate labels and certification marks by qualified electrical testing laboratories. This rule also indicates it is not the NEC’s intent that internal wiring or construction of equipment be inspected again at the time of installation, other than to detect damage or alterations. 

Some qualified electrical testing laboratories can provide field-evaluation services for electrical systems or equipment that require an overall listing or certification for approval. These services are typically unique to only the facility and location where the field evaluation is performed. The field evaluation generally includes verification of conformity to applicable standards and codes. 

Section 110.2 indicates conductors and equipment required or permitted by the NEC are acceptable only if “approved.” This requirement aligns directly with the definition of approved, which triggers the AHJ’s direct involvement. Section 110.3 outlines very important approval factors for the AHJ: in sequence, examination, identification, installation, use and listing (product certification) of equipment. Under examination in subdivision (A), an inspector uses multiple factors to carry out approval responsibilities, including suitability related to conformance, mechanical strength, wire bending space, electrical insulation heating effects and other factors related to practical safeguarding of persons and property.

In subdivision (B), the rules are about following the installation and use of instructions included with equipment. Subdivision (C) covers listing, the approving factors include product testing, evaluation and product certification (listing), which must be performed by qualified electrical testing laboratories. OSHA provides a list of qualified electrical testing laboratories at osha.gov/dts/otpca/nrtl/nrtllist.html. AHJs usually refer to this list when asked which qualified electrical testing laboratories they recognize or accept. Inspection jurisdictions rely heavily on the use of listed equipment as a basis for issuing approvals.

It is important that jurisdictions adopt and enforce the latest edition of the code. Jurisdictions that do not could handicap inspectors that have to apply the code to new technologies. 

Serious consideration should be given to this when jurisdictions are engaged in processes of NEC legal adoption. It is the right thing to do for the best interest of inspectors to assist with approval processes and for public safety.

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