Part 313 min

3.1 Overhead lines, buried lines and the things that reach them

Overhead power lines kill people who are not doing electrical work. A ladder, a scaffold frame, a concrete pump boom, an aluminum pole — something long goes up, and the line that has been there for thirty years does not move. CPWR's analysis of a decade of federal data found that a majority of fatal indirect electrical contacts in construction — 86.0% — involved exposure to 220 volts or greater, which is the signature of overhead wire voltage (CPWR Data Bulletin, November 2022).

1 Three case files, one pattern

Read these together before the rules, because the rules make more sense afterward. All three are OSHA Accident Search summaries, cited by number and date.

What actually contacted the line
Date	Summary Nr	What happened
07/03/2024	168077.015	Two workers were taking down a 44-foot aluminum extension ladder, lost control of it, and the ladder contacted an overhead line. One died of electrocution.
08/17/2024	169332.015	A worker erecting the sixth level of a scaffold had a frame member contact an energized overhead line. He was shocked and fell about 30 feet; he died of both.
01/15/2025	173510.015	A concrete pumping crew was placing concrete. The employee moved the hose boom, which contacted a nearby high-voltage overhead line. He was fatally injured.

A ladder crew, a scaffold crew, a concrete crew. Nobody was working on electricity. In each case the fatal object was the thing they were paid to move.

2 The four questions that prevent all three

1
Is there a line, and where exactly? Walk the whole path, not the work point. The ladder in the first case was being carried, not climbed.
2
Can it be deenergized or covered? 1910.333(c)(3) puts this first: arrange with the utility to deenergize and ground, or provide guarding, isolation or insulation. Utilities install line covers routinely; the request needs lead time, which is why it belongs in planning, not in the morning huddle.
3
What is the longest thing we will hold up today? The clearance is measured from that object, not from the person (1910.333(c)(3)(i)(A)).
4
Who is watching, and can they stop the lift? A dedicated spotter with authority to stop, positioned to see the gap, not the load.

10 ft, unqualified persons and equipment

Measured from the longest conductive object

A spotter who can stop the lift

The utility, in the plan not the huddle

3 What the construction standard adds

Subpart K states the general duty in 1926.416(a)(1): no employer shall permit an employee to work in such proximity to any part of an electric power circuit that the employee could contact it in the course of work, unless the employee is protected by deenergizing the circuit and grounding it, or by guarding it effectively by insulation or other means.

And 1926.416(a)(3) requires the employer, before work begins, to ascertain by inquiry or direct observation, or by instruments, whether any part of an energized power circuit — exposed or concealed — is located where the work may bring a person, tool or machine into physical or electrical contact with it. The employer must post and maintain warning signs where such a circuit exists, and advise employees of the location of the lines, the hazards involved and the protective measures to be taken.

Three verbs in one paragraph: find out, post, tell. If the crew does not know where the lines are, the paragraph has not been met.

4 Ladders, scaffolds and the equipment rules that back it up

Rules that keep long objects away from lines
Requirement	Source
Portable ladders must have nonconductive siderails where the employee or the ladder could contact exposed energized parts	29 CFR 1910.333(c)(7)
Use non-conductive wood or fiberglass ladders when working near power lines; stay at least 10 feet away and assume the lines are energized	OSHA FS-3942, Working Safely with Electricity
Vehicles and mechanical equipment capable of elevating part of their structure keep 10 feet, reduced to 4 feet only in transit with the structure lowered	1910.333(c)(3)(iii)(A)
Employees on the ground may not contact that vehicle or its attachments unless protected or unless the machine cannot come closer than allowed	1910.333(c)(3)(iii)(B)
Objects without an insulating rating for the voltage involved are considered conductive	Note to 1910.333(c)(3)(i)

Common mistake: using a fiberglass ladder as if it were an insulator. Fiberglass side rails are non-conductive when they are clean and dry. Wet, dusty with conductive material, or with a metal-reinforced rail, they are not a rated insulating device, and no ladder is rated for line contact.

5 Buried lines: the hazard with no visual warning

Underground conductors get less attention because nothing is visible to look up at. OSHA FS-3942 puts overhead and buried lines in the same sentence — both "are especially hazardous because they carry dangerously high voltage" — and tells workers to look for buried power line indicators as well as overhead lines.

The construction standard has a specific rule for the moment when nobody knows where the line is. 1926.416(a)(2): "In work areas where the exact location of underground electric powerlines is unknown, employees using jack-hammers, bars, or other hand tools which may contact a line shall be provided with insulated protective gloves."

Insulated gloves are the last thing between a worker and an unknown cable. The first thing is the one-call ticket, the marks on the ground and the soft-dig practices that come with them — and a ticket is a legal requirement of state law in every state, not a courtesy.

6 If contact happens

A machine in contact with an energized line is a live object sitting on the ground, and the ground around it may be energized too. The rules of Part 1 apply with the volume turned up.

1
Nobody touches the machine. That is 1910.333(c)(3)(iii)(B), and it is also common sense that disappears when a colleague is in the cab.
2
The operator stays in the cab if the machine can stay put, until the utility confirms the line is deenergized.
3
If they must leave — fire, for example — they jump clear without touching machine and ground at the same time, and shuffle away with small steps and feet together, because the ground itself has a voltage gradient.
4
Call the utility, then emergency services. Only the utility can confirm the line is dead, and reclosers can re-energize a line automatically after a fault.

7 Planning the site so the line stops mattering

Distance rules protect a crew that is already close to a line. Site planning stops the crew from ever getting there, and it is cheaper than everything else in this chapter.

Design decisions that remove overhead-line exposure
Decision	What it removes
Locating the material lay-down area, the trash chute and the dumpster away from the line corridor	The repeated exposure — the twentieth trip past a drop is the one that goes wrong
Placing the concrete pump, the crane and the lift on the side of the building away from the service	Boom swing over an energized conductor, the mechanism in Summary Nr 173510.015
Setting the ladder and scaffold staging point so long items are raised in an open bay	The carry and the raise, which is where the ladder and scaffold cases happened
Asking the utility for a cover-up or an outage during the specific phase that needs the space	The hazard itself — the first control in 1910.333(c)(3)
Marking a ground-level exclusion zone under the line with cones or fence	The judgment call, by making the boundary visible from every angle

Notice that four of the five are decisions made before anybody arrives on site, by people who will never touch a conductor. That is the honest lesson of the three case files at the top of this chapter: the crews were doing exactly what they were sent to do, in the place they were sent to do it.

Common mistake: asking the utility on the morning of the pour. Cover-up and outage requests take days to weeks depending on the utility and the circuit. A request that arrives with the concrete truck gets refused, and the crew works to a distance rule instead of to the control that would have removed the hazard.

Key takeaways

Overhead line fatalities happen to ladder, scaffold, concrete and rigging crews — the fatal object is usually the thing the crew was paid to move.
The first control is deenergizing and grounding the line, or guarding it — arranged with the utility, in the plan, not on the morning of the pour (1910.333(c)(3)).
Clearance is measured from the longest conductive object a person may contact, and unrated objects count as conductive.
1926.416(a)(3) requires the employer to find out where energized circuits are, post signs and tell the crew, before work begins.
Where the location of buried lines is unknown, 1926.416(a)(2) requires insulated protective gloves for workers using jackhammers, bars and other hand tools.
After a contact: nobody touches the machine, the operator stays put if possible, and only the utility can declare the line dead.

Free educational content — not OSHA-authorized training, no certificate or card issued. Follow your employer's program and the standards cited.