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.

February 7, 2000

Mr. Steven M. War
c/o Mr. James Gromada
Fish & Richardson P.C.
601 Thirteenth Street, NW
Washington, D.C. 20005

Dear Mr. War:

Thank you for your November 3, 1999 letter to the Occupational Safety and Health Administration's (OSHA's) [Directorate of Enforcement Programs (DEP)]. Your letter has been referred to the [Office of General Industry Enforcement (GIE)] for an answer regarding Nationally Recognized Testing Laboratory (NRTL) certification for electrical sewer inspection equipment. Your letter describes an electrical sewer inspection system and its use in three scenarios. Per telephone discussions, between you and [a member] of my staff, your questions deal with OSHA's General Industry standards rather than Construction standards. Your description and scenarios have been restated below for clarity.

Equipment Description:

You have described a sewer inspection system that consists of a control unit to be located outside of the sewer location and a small motorized vehicle with a mounted video camera to travel inside of the sewer. The vehicle will be controlled with a tether which supplies AC power to operate the vehicle and the camera. Overall system voltages are assumed to be in excess of 50 volts with the control unit being cord and plug connected. Parts of the equipment may be used in wet or conductive locations.

Scenario 1: Non-Hazardous Locations:

The employer has determined that the sewer inspection equipment will be used outdoors but not in a hazardous (classified) location. Assume that the equipment is "of a kind" which an NRTL certifies and that is not custom made for the employer (i.e., it is "off-the-shelf" equipment).

Question: Are we correct in our understanding that in order to be compliant with OSHA regulations, this equipment must be NRTL certified, listed or labeled?

Response: Yes, in response to your scenario, §1910.303(a) requires that electrical conductors and equipment are acceptable only if approved. Approved means "acceptable" to the Assistant Secretary of Labor and approved within the meaning of the specific standard, if it is accepted, certified, listed, labeled, or otherwise determined to be safe by a Nationally Recognized Testing Laboratory (NRTL).

Scenario 2: Class I, Division 1 Hazardous (classified) Locations:

The employer has determined that the sewer inspection equipment will be used in a hazardous (classified) location (Class I, Division 1). Assume that the equipment is "of a kind" which an NRTL certifies for a Class I, Division 1 location and for the particular Class I group classification hazard present, and is not custom made for the employer (i.e., it is "off-the-shelf" equipment).

Question: Are we correct in our understanding that, in order to be compliant with OSHA regulations, this equipment must be NRTL certified, listed or labeled for the Class I, Division 1 location; as an alternative, the employer can self-demonstrate compliance to the National Electric Code, NFPA-70, or a similar equipment safety guideline that provides protection to employees from the hazards arising in the location?

Response: In response to your question, §1910.307 regulates the use of electric equipment and wiring in hazardous locations. Electric equipment, wiring, and installations may not be used in hazardous locations unless they are either intrinsically safe, approved for the hazardous location, or safe for the hazardous location. Pursuant to §1910.307, the sewer inspection equipment you discussed may be used in a Class I, Division 1 location if: (1) the equipment is NRTL certified, listed or labeled for Class I, Division 1 location or (2) the equipment is NRTL certified, listed or labeled for nonhazardous use and you can demonstrate that the equipment is of a nature that will provide your employees with protection from the hazards that are associated with the Class I, Division 1 location. While we have not examined the sewer inspection equipment you described and cannot know the precise nature of the environments in which it would operate, we have serious doubts as to whether you could apply any of the protective techniques provided in NFPA 70 (or other equivalent and effective guidelines) as would be necessary to demonstrate that this "off-the-shelf" equipment is safe for Class I, Division 1 locations. If you are unable to make such a demonstration, it would be necessary to use only equipment that is listed for Class I, Division 1 locations.

Scenario 3: Dual Usage:

The employer wants to use the same sewer inspection system in both hazardous (classified) locations (Class I, Division 1) and in nonhazardous locations.

Question: Are we correct in our understanding that the equipment must be compliant with OSHA regulations for Class I, Division 1 locations?

Response: Yes, the system would obviously have to be approved for use in both Class I, Division 1 locations involving flammable vapors, liquids or gases, as well as in nonhazardous locations where such flammable vapors, liquids or gases are absent but where specific grounding standards must be met.

Thank you for your interest in occupational safety and health. We hope you find this information helpful. Please be aware that OSHA's enforcement guidance is subject to periodic review and clarification, amplification, or correction. Such guidance could also be affected by subsequent rulemaking. In the future, should you wish to verify that the guidance provided herein remains current, you may 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 Programs]

[Corrected 6/2/2005]