High Voltage Lines Training Guides

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Labor Occupational Health Program

Summary Statement

Training on the dangers of high voltage lines with information on what constitutes high voltage, how to avoid contact and what to do if someone gets a shock - includes discussion questions and a sign-off form. Part of a collection. Click on the 'collection' button to access the other items.

These tailgate/toolbox talks were developed for use under California OSHA regulations. The complete set is available from the Labor Occupational Health Program at UC Berkeley. For ordering information, visit the website (www.lohp.org) The American Conference of Government Industrial Hygienists (ACGIH) has adapted these talks to apply to federal OSHA regulations. To contact ACGIH, visit its web site (www.acgih.org).

    Before you begin the meeting...

  • Does this topic relate to the work the crew is doing? If not, choose another topic.

  • Did you read this Training Guide and fill in the blanks where thePencil Icon appears? (To find the information you need, look over the Safety Walkaround Checklist for this topic.)

Begin: Electricity jumps! Always keep yourself and your equipment a safe distance from high voltage lines. Even low voltage can injure or kill you, but today we’ll be talking about high voltage. About 700 U.S. workers are killed by electricity each year, many because they got too close to a high voltage line. We’ll explain some steps to take if someone gets an electric shock—but even the best emergency care can’t always save a life. It’s best not to get too close to electricity in the first place.

You or a crew member may want to add a personal story about high voltage electricity.

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Next, discuss with the crew where there may be danger from high voltage lines at this particular job site:



After each question, give the crew time to suggest possible answers. Use the information following each question to add points that no one mentions.

1. Electricity can be dangerous at any voltage, but our subject today is high voltage. Does anyone know what we mean by high voltage electricity?

  • Over 600 volts.

2. How far away should you stay from an overhead high voltage line?

  • People should stay between 6 and 20 feet away, depending on the voltage. The higher the voltage, the farther electricity can jump. No part of your body should come within this minimum clearance distance.
  • Most tools, equipment, and machinery should also stay between 6 and 20 feet away.
  • Lifting and hoisting machinery (like cranes) should stay between 10 and 42 feet away from the line, depending on the voltage.
  • An electric line might move (due to strain on the supporting structures, etc.) Your clearance distance must also allow for this possible movement.
Pencil Icon Use the Safety Walkaround Checklist for this topic to fill in the following chart. If voltages and minimum clearances are different on different parts of the site, list them separately for each area. Explain the chart to the crew.

Area On Site

Line Voltage
Clearance for People and Most Equipment
Clearance for Lifting and Hoisting Machinery

3. What if you have to work within the minimum clearance distance?

  • Make sure the electric line is de-energized.
  • Consider any line to be “live” unless you know it is de-energized and it is visibly grounded.

4. Keep all tools and equipment away from high voltage lines. You can get a serious shock if anything you’re using or carrying accidentally contacts a line. What are some tools and equipment that you should be especially careful with?

  • Metal ladders
  • Long pipes
  • Tree trimming equipment
  • Cranes
  • Scaffolds
  • Antennas
  • Extension rollers used in painting
  • Lifting equipment
  • 5. According to Cal/OSHA, there should be two signs on all cranes, derricks, power shovels, pile drivers, and similar machinery, warning about the clearance distance from high voltage lines. What information is on these signs?

    • They say that operators should keep this equipment at least 10 feet from high voltage lines that carry 50,000 volts or less. The clearance distance is more if the line carries higher voltage. These signs are required—let your supervisor know if they’re not there.

    6. If your electrical resistance is low when you get a shock, more electricity will flow through your body. That will usually cause more injury. What are some things that can lower your resistance?

    • Working in a wet or damp location
    • Using wet tools
    • Sweating
    • Working in contact with good conductors like metal pipes, tanks, or boilers.

    7. What kinds of injuries can you get from a high voltage electric shock?

    • High voltage can stop your heart or your breathing.
    • It can also cause fibrillation—a fast, irregular heartbeat.
    • You can get a serious burn—external or internal.
    • You can fall off a ladder or scaffold and get injured.
    • Even if you’re not on a ladder or scaffold, high voltage can “throw” you—causing fractures or broken bones.

    8. What should you do if someone gets an electric shock?

    • Don’t touch the person until power has been disconnected.
    • Call 911.
    • Calm and reassure the injured person. Don’t move them until trained help arrives.
    • Notify the first aid provider, clinic, or supervisor as soon as possible.
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    Name of on-site first aid provider or designated local clinic:



    Explain: Most of the safety measures we’ve talked about are required by Cal/OSHA. We have to take these precautions—it’s the law. I have a Checklist of the Cal/OSHA regulations on high voltage electricity. If you’d like to know more, see me after the meeting.


    (Only if applicable.) Besides the Cal/OSHA regulations, we have some additional company rules about high voltage electricity.

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    Discuss company rules:_______________________________



    Ask: Do you have any other concerns about high voltage electricity? Do you see any problems on our job? (Let the steward answer first, if there is one.)

    What about other jobs you’ve worked on? Have you had any experience with high voltage electricity that might help us work safer on this job?

    Sign Off Form

    Date Prepared:_________________________ By:_______________________
    Project Name/No.______________________ Location:___________________
    Printed Name

    Laborer Electrocuted by Energized Crane

    A 26-year-old construction laborer was electrocuted when he tripped and came into contact with a crane. The crane had become energized through accidental contact with a high voltage line overhead.

    The crane was in an area with both telephone and high voltage lines, and the crane operator was aware of them. Earlier in the day, the crane had brushed against telephone lines and had to be repositioned. However, at this time in the late afternoon, the operator's vision of the high voltage lines was obstructed because of the sun's position. The auxiliary line of the crane made contact with the high voltage line. The auxiliary line burned in two and the ball/hook assembly fell to the ground. Voltage was 16,000 volts.

    The laborer was carrying a wire rope over to be used to attach a pile of plywood to the crane's hook. The crane operator and laborer were both startled by the fall of the ball/hook assembly. The boom of the crane momentarily drifted, contacting the high voltage line directly.

    The laborer was carrying a wire rope over to be used to attach a pile of plywood to the crane's hook. The crane operator and laborer were both startled by the fall of the ball/hook assembly. The boom of the crane momentarily drifted, contacting the high voltage line directly.

    May 12, 1992

    What should have been done to prevent this accident?

    Preventive Measures

    Cal/OSHA investigated this accident and made the following recommendations.

    Employers should:
    • Provide information to workers on what kinds of hazards to look for and how to avoid them.
    • Develop and implement strict safety procedures when working with a crane in the vicinity of high voltage power lines.
    • Contact the local electric power company and have the power turned off when working within a certain distance of high voltage power lines.