1926.959(d)(3)(iii): Protection From Mechanical Equipment Contact
Each employee must be protected from hazards if mechanical equipment contacts energized lines or equipment, so that no one is exposed to hazardous differences in electric potential. Unless the employer can show other methods protect employees, the measures must include using the best available ground, bonding equipment together, ground mats and insulating protective equipment or barricades.
Key takeaways
- 1926.959(d)(3)(iii) is part of OSHA's construction standards (29 CFR Part 1926, Subpart V).
- OSHA cited it 3 times in the last 3 years, in 3 inspections, with $18,200 in current penalties.
- 1 death is linked to inspections that cited this rule.
- Related part: 1926.959(d) Operations near energized lines or equipment (20 citations).
- Free 5-minute toolbox talk for your crew below.
In this article
What this rule covers
29 CFR 1926.959(d)(3)(iii) is one requirement inside 1926.959 Mechanical equipment, an OSHA construction standard (Part 1926, Subpart V). It includes 4 sub-paragraphs. The official text below is copied word for word from the Electronic Code of Federal Regulations (eCFR). The numbers, injury cases and training on this page show how OSHA enforces it on real job sites.
Official text
(iii) Each employee shall be protected from hazards that could arise from mechanical equipment contact with energized lines or equipment. The measures used shall ensure that employees will not be exposed to hazardous differences in electric potential. Unless the employer can demonstrate that the methods in use protect each employee from the hazards that could arise if the mechanical equipment contacts the energized line or equipment, the measures used shall include all of the following techniques: 3 citations
(A) Using the best available ground to minimize the time the lines or electric equipment remain energized,
(B) Bonding mechanical equipment together to minimize potential differences,
(C) Providing ground mats to extend areas of equipotential, and
(D) Employing insulating protective equipment or barricades to guard against any remaining hazardous electrical potential differences.
Appendix C to this subpart contains information on hazardous step and touch potentials and on methods of protecting employees from hazards resulting from such potentials.
Source: eCFR, text current as of 2026-10-15. Read all of 1926.959.
Injuries linked to this rule
1 death is linked to inspections where OSHA cited 1926.959(d)(3)(iii).
At 1:00 p.m. on September 12, 2024, Employee #1 was raising the boom of a vacuumtruck to install an extension. During the operation, the boom made contact with an overhead electrical line, resulting in electrocution.
Where and how often it was cited
Free toolbox talk
A 5-minute crew talk on 1926.959(d)(3)(iii), plus alerts when this rule changes. Free.
OSHA interpretation letters
None exist. OSHA has not published a letter of interpretation for 1926.959(d)(3)(iii).
Related parts of this rule
- 1926.959(d) Operations near energized lines or equipment 20 citations
- 1926.959(d)(3) Extra precautions 10 citations
- 1926.959(d)(1) Minimum approach distance 5 citations
- 1926.959(d)(2) Observer 5 citations
- 1926.959(d)(3)(ii) 4 citations
- 1926.959(d)(3)(i) 2 citations
Get your crew competent
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Frequently asked questions
What must the measures prevent?
Exposure to hazardous differences in electric potential.
What techniques are required?
Best available ground, bonding mechanical equipment together, ground mats and insulating protective equipment or barricades.
Can other methods be used?
Only if the employer can demonstrate they protect each employee.
About this page
Sources
- 29 CFR 1926.959 (eCFR), text current as of 2026-10-15
- U.S. Department of Labor enforcement data: OSHA inspections, citations and accident records, copied nightly; data as of 2026-10-19
3-year window. Federal OSHA only; state-plan rules are not counted. Plain-language text is a summary, not legal advice; the official text controls. Black Belt Safety is not part of OSHA or the Department of Labor.