August 16, 2023

Mr. Josh Ewing
Business Manager, IBEW Local Union 29
986 Greentree Road
Pittsburgh, Pennsylvania 15220

Dear Mr. Ewing:

Thank you for your letter to the Occupational Safety and Health Administration (OSHA), requesting clarification of OSHA requirement regarding the application of the required minimum approach distance (MAD) for a 23 kilovolt (kV) electric distribution system covered under 29 CFR 1910.269 standards. This letter constitutes OSHA's interpretation only of the requirements herein and may not be applicable to questions not in your original correspondence. Your paraphrased scenario, questions, and our responses are as follows.

Scenario: A worker is assigned to perform work on a 4 kV conductor that is adjacent to a 23 kV conductor. Work performed on the 4 kV conductor requires encroachment into the 23 kV conductor minimum approach distance (MAD). The 23 kV conductor is covered with insulating equipment. Workers are provided and use gloves rated for performing work on the 4 kV conductor, but which would not be sufficient protection from an exposed 23 kV conductor.

Question 1: If the 23 kV conductor is covered with insulating equipment, can the worker encroach on the MAD for that covered 23 kV conductor while performing work on the adjacent exposed 4 kV conductor and wearing rubber insulating gloves only rated for 4 kV?

Response: Yes. Both 29 CFR 1910.269(l)(3)(iii) and (l)(5)(ii) allow entry into the minimum approach distance if the worker is insulated from energized parts by appropriate personal protective equipment (PPE), the energized parts are appropriately insulated from the worker, or live line work is being performed per 29 CFR 1910.269(q)(3). Therefore, if the 23 kV conductor is covered with appropriate insulating equipment in each direction to such a distance that the worker’s reasonably likely movements cannot reach into the MAD for any exposed energized portion of the 23kV line and the worker only encroaches on the MAD of the conductor in the area where proper insulation is installed, the line worker could perform work on the 4 kV conductor using rubber insulated gloves rated for the 4 kV exposed line. However, appropriately rated PPE must be used to place and remove the insulated cover on the 23 kV line, and any work that involved disturbing/removal of the insulation on the adjacent 23kV line would require a level of PPE appropriate for that higher voltage.

Question 2: If an employee is able to get within inches of the hard cover-up for 23 kV distribution and sub-transmission lines, should the hard cover-up be rated for only “brush” contract, meaning you are only safe if you bump into it for a minimum amount of time?

Response: The insulating equipment you describe must meet 29 CFR 1910.137(b) design requirements. The note to the paragraph (b) indicates that “Plastic guard equipment is deemed to conform to the performance requirements of paragraph (b) of this section if it meets, and is used in accordance with, ASTM F712-06 (2011), Standard Test Methods and Specifications for Electrically Insulating Plastic Guard Equipment for Protection of Workers. OSHA does not have specific definition for brush contact; however, you may refer to ASTM F712-06 (2011), which addresses accidental brush contact.

Thank you for your interest in occupational safety and health. We hope you find this information helpful. OSHA’s requirements are set by statute, standards, and regulations. Our letters of interpretation do not create new or additional requirements but rather explain these requirements and how they apply to particular circumstances. This letter constitutes OSHA’s interpretation of the requirements discussed. From time to time, letters are affected when the Agency updates a standard, a legal decision impacts a standard, or changes in technology affect the interpretation. To assure that you are using the correct information and guidance, please consult OSHA’s website at https://www.osha.gov. If you have any questions, please feel free to contact the Directorate of Enforcement Programs at (202) 693-2100.

Sincerely,

Kimberly A. Stille, Director
Directorate of Enforcement Programs