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    SiteKiln, Your rights on site. In plain English.

    Buried Services: 811, and the First Ten Minutes

    The call before you dig, the color code, the hand-dig zone, and exactly what to do in the minutes after you hit something.

    IF YOU HIT SOMETHING: the first ten minutes

    • STOP WORK. Do not try to repair it, and do not move the equipment if moving it could make it worse.
    • GAS: evacuate upwind immediately. Kill every ignition source: engines, generators, phones, cigarettes. Do not switch anything on or off. Call 911 first, then the utility. Gas is the one that kills people who stayed to look.
    • ELECTRIC: treat it as live even if only the coating is scratched. Nobody touches the machine or the ground near it. If you are on the machine, stay on it. Call 911, then the utility.
    • WATER or SEWER: stop work, isolate if you safely can, call the owner. The risk is undermining and contamination, not usually immediate life safety.
    • FIBER or COMMS: no life-safety risk, but call the owner immediately. Repair costs escalate the longer it is unreported.
    • Report EVERY strike, including a nick to a coating. An unreported scrape becomes someone else's failure months later.

    The APWA color code

    Red Electric power
    Yellow Gas, oil, steam, petroleum
    Orange Communication, alarm, signal
    Blue Potable water
    Purple Reclaimed water, irrigation
    Green Sewer and drain
    Pink Temporary survey markings
    White Proposed excavation route

    Before you dig

    Call or click 811 routes to your state's One Call center
    Notice Commonly 2 to 3 full business days, but it is set by STATE law and varies
    Positive response Each notified utility posts a status against your ticket. Check it before breaking ground. Marks alone are not clearance.
    If nobody responds OSHA 1926.651(b)(2) lets you proceed with caution using detection equipment if utilities cannot respond within 24 hours, or a longer period set by state law, or cannot establish exact location
    Marks expire Validity is set by state. When they lapse or are destroyed, re-notify. Do not dig to old paint.

    The tolerance zone

    • A buffer either side of the mark, plus the diameter of the line itself. Width is set by state law, commonly 18 to 24 in.
    • Inside it: hand digging, pot-holing or vacuum excavation. No mechanical equipment, no pointed shovels, until the line is exposed and confirmed.
    • OSHA 1926.651(b)(3): once excavation approaches the estimated location, the exact location must be determined by safe and acceptable means.
    • OSHA 1926.651(b)(4): while the excavation is open, utilities must be protected, supported or removed as needed to safeguard employees.
    The notice period, tolerance zone width, mark validity and penalties are all set by STATE one-call statutes and they genuinely differ, so the figures here are the common range rather than your rule. Federal law sets minimum program standards and funds state programs; the operative excavator duties and the enforcement come from your state. Confirm your state's notice days and tolerance zone with your one-call center before you plan a dig.

    Sources: call811.com · apwa.org · osha.gov

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