PG&E Tips of the Trade
Understanding the tolerance zone
811 Know what's below. Call before you dig.

Dig safe
Damage to a natural gas pipeline can cause a gas leak that can result in a fire, explosion or injuries.

Call 811 or use the online ticket system at at least two working days prior to starting work.

Look up and live
Look up and around before lifting or moving irrigation pipes or ladders. Check for power lines, poles and support wires before driving or operating equipment.

Injury or possible death can result from contact with any overhead or underground power line, large or small. Even the service wires that run from utility poles to buildings and pumps are potentially dangerous.

Keep yourself and all tools and equipment at least 10 feet away from overhead power lines. Only qualified line clearance personnel can work in the 10-foot safety zone.

High voltages require a larger safety zone. Before work begins, your crew leader must brief you about power line voltages in your work area and the clearances required to get the job done safely.

Make the call
If you suspect a gas leak or if you contact a gas pipeline or electric power line, call 911 immediately then PG&E at:

Review these tips with coworkers at your tailgate or tool box meetings before work begins to help avoid potential hazards when working near underground utilities.

 tolerance zone | 24 inches

What is the tolerance zone?
The tolerance zone is a safety area that spans the width of a marked underground utility plus a specified distance from each indicated outside edge of the utility. The specified distance varies from state to state. It is 24 inches in California.

If you are digging within the tolerance zone in California, any underground facilities that are in conflict with your excavation must be located with hand tools and protected before power equipment is used. If you wish to use vacuum excavation to locate marked facilities within the tolerance zone, you must first obtain the permission of the facility operator and you must inform the 811 service of your intent to use a vacuum excavation device when obtaining a dig ticket.

Dig with care
When digging in the tolerance zone, use reasonable care and these nondestructive digging methods:

  excavator digging
  • Hand digging with a blunt shovel. Never use a pickaxe or pointed spade, and never stomp on a shovel with both feet. That’s a sure way to damage a utility line. Instead, use a blunt shovel to loosen soil, working at an angle.
  • Vacuum excavation. This method uses suction and water to quickly and safely remove soil. Be mindful of water pressure; use lower pressure and tips with multiple nozzles.

Proceed with caution
Once you have exposed buried utilities, proceed with extreme caution. Power digging equipment can damage a section of electrical conduit or pipeline in no time. Even hand digging can compromise buried utilities by removing supporting soil. Take all necessary precautions to protect buried utilities from damage.

Would you like to know more?
Additional overhead and digging guidelines, emergency procedures and training tools can all be found at no charge to you on the PG&E
e-SMARTworkers website. Here you can also order free safety materials for contractors and tree workers.

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