Sheet 27Mix-up sheet · Cranes, rigging, heavy equipment and work zones
Crane clearance from power lines: 20 feet vs 10 feet
Plan for 20 feet. Under 29 CFR 1926.1408, if crane work could bring the equipment, load line or load within 20 feet of a power line rated up to 350 kV, the employer chooses a protection option before work begins. Once the utility confirms the line runs at 50 kV or less, Table A's minimum clearance for that line is 10 feet.
Both from 29 CFR 1926.1408, as of October 2026scroll →
Point
20-foot clearance
Table A clearance
When it is used
Voltage not yet known; lines up to 350 kV
Voltage confirmed by the utility
What it asks
Keep everything at least 20 ft from the line
Keep the distance Table A lists for that voltage
Line at 50 kV or less
20 ft
10 ft
Higher voltages
20 ft, up to 350 kV
Distances that grow with voltage
Added measures
Planning meeting, warning line or barricade, non-conductive tag lines if tag lines are used, plus one device such as a dedicated spotter
Planning meeting, warning line or barricade, non-conductive tag lines if tag lines are used, plus one device such as a dedicated spotter
Lines are treated as energized until the utility confirms they are de-energized and visibly grounded at the worksite (29 CFR 1926.1408(e)).
≠ marks the rows where the two differ.
Talking point 02
Why the distance moves from 20 to 10
The 20 feet is a planning distance. Before assembly, the employer marks out the work zone, by boundaries or as the full circle the crane could swing at maximum working radius, and asks whether anything in it could come within 20 feet of a line. Nobody on the ground can tell a line's voltage by looking at it, so 20 feet covers anything up to 350 kV until the utility supplies a number.
Ten feet is the smallest distance in Table A, and it applies only after the voltage is confirmed at 50 kV or less. So once the utility gives you a voltage, the distance you plan to can change. Above 50 kV the table steps up; read the current rows on eCFR instead of trusting memory. Rigging, signals and the rest of crane work sit on cranes, rigging, equipment and work zones.
Talking point 03
From site plan to first lift
The sequence 29 CFR 1926.1408 lays out for cranes near power lines up to 350 kV.Talking point 04
Ten feet outside the crane standard
Lines at 50 kV or less, by kind of workscroll →
Work near the line
Minimum
Cranes and derricks, voltage confirmed (1926.1408, Table A)
10 ft
Other mechanized equipment (1926.600(a)(6))
10 ft
Scaffolds near uninsulated lines (1926.451(f)(6))
10 ft
Excavators, backhoes and loaders fall outside the crane standard even when they are rigged to lift a load (29 CFR 1926.1400(c)).
Talking point 05
Lifts near the lines
Read each card through to the voltage, where it gives one, before you settle on a distance.
Card 1 of 6 · 0 right
Card 1
Crane work is planned near a transmission line, and the utility confirms in writing that it operates at 138 kV. Under Table A of 29 CFR 1926.1408, what minimum clearance must the crane, load line and load keep?
Pick an answer. A short note for each option, A to D, appears here.
ATen feet is the Table A minimum only for lines up to 50 kV. A 138 kV line needs more.
BTwenty feet is the planning distance while the voltage is unknown, and the Table A row for over 200 to 350 kV. With 138 kV confirmed, the table allows less.
CTwenty-five feet is the Table A row for lines over 350 kV up to 500 kV.
DCorrect: Table A lists 15 feet for lines over 50 kV up to 200 kV, which covers a confirmed 138 kV line.
Card 2
During a lift, a mobile crane's load line touches an energized overhead line. The operator is unhurt, and there is no fire. What should the operator do?
Pick an answer. A short note for each option, A to D, appears here.
ACorrect: The cab is the safest place unless fire or another emergency forces evacuation, and others must keep clear of the crane and load.
BStepping down and approaching the load exposes the operator and the riggers to the energized machine and the charged ground around it.
CHolding the rail while touching the ground is exactly how a body completes the path to ground.
DInspecting the boom means touching an energized machine. Nobody approaches it until the utility de-energizes the line.
Card 3
A crane will set roof trusses from a spot 30 feet from a street power line of unknown voltage. At full working radius, the swinging load could pass within 15 feet of the line. Do the 29 CFR 1926.1408 power-line precautions apply?
Pick an answer. A short note for each option, A to D, appears here.
AWhere the crane sits does not settle it. The rule looks at how close the equipment, load line or load could get.
BUnknown voltage is the case the 20-foot planning distance is built for, so it triggers the precautions.
CCorrect: Any part of the equipment, load line or load that could come within 20 feet of a line up to 350 kV brings in a protection option before work begins.
DThe rule counts the load and load line as well as the boom, and 10 feet applies only after the voltage is confirmed at 50 kV or less.
Card 4
A crane could come within 20 feet of an energized line, and the employer will keep the 20-foot clearance with encroachment-prevention measures. Who must take part in the required planning meeting?
Pick an answer. A short note for each option, A to D, appears here.
AThe competent person may well attend, but the rule names the operator and the workers who will be in the area of the equipment or load.
BCorrect: The meeting brings together the operator and the workers who will be around the equipment or load to review the lines and the encroachment controls.
CThe utility and engineers can supply information, but the meeting is for the people who will work around the crane.
DRiggers and tag-line handlers are exposed too, so they must know where the lines are and which controls are in place.
Card 5
A crane will work near a transmission line rated at 500 kV. Under OSHA's crane standard, what distance takes the place of the 20-foot planning distance used for lines up to 350 kV?
Pick an answer. A short note for each option, A to D, appears here.
ATwenty-five feet is the Table A row for a confirmed voltage over 350 kV up to 500 kV, not the substitute for the 20-foot planning distance.
BThirty-five feet is the Table A row for lines over 500 kV up to 750 kV.
CThe 20-foot planning distance stops at 350 kV, so a 500 kV line is outside it.
DCorrect: For lines over 350 kV up to 1,000 kV, 29 CFR 1926.1409 substitutes 50 feet wherever 1926.1408 says 20 feet.
Card 6
A crane operator cannot see the landing area on the far side of a building where a load of trusses will be set. What does OSHA require for this lift?
Pick an answer. A short note for each option, A to D, appears here.
ACorrect: When the operator's view of the point of operation is obstructed, OSHA requires a signal person who is qualified through evaluation and uses agreed signals.
BExperience is not the same as qualification; the crane rules require a signal person evaluated as qualified.
CSlower swing speed does not restore the operator's view of the landing area, so a signal person is still required.
DA secondhand relay adds delay and confusion, and the person giving signals must be the qualified signal person who can see the load.