Working Near Electricity Cables

Underground electricity cables carry voltages from 230V domestic supplies to 132,000V on transmission circuits.
Contact with a live buried cable during excavation causes electrocution, severe burns, and arc flash explosions.
HSG47 requires cable location using service plans and CAT and Genny scanning before any excavation work begins.
Electricity cables may be directly buried, laid in ducts, or encased in concrete troughs at varying depths.
Warning tiles or coloured tape are often laid above buried cables but may be missing, displaced, or buried deeper.
Within 500mm of a known cable, only hand digging using insulated tools is permitted — no machine excavation.
A cable strike can affect the wider supply network, cutting power to homes, hospitals, and critical infrastructure.
Black, red, and yellow plastic ducts typically contain electricity cables — treat all unknown ducts as potentially live.
High voltage cables can arc through soil and injure workers near but not touching the cable itself.
Damaged cables must never be touched — isolate the area, keep everyone clear, and call the network operator immediately.

Electrocution	Contact with a buried live cable kills instantly at higher voltages and causes severe burns at lower voltages.
Arc flash	High voltage cables create arc flash explosions through soil that burn workers standing near the strike point.
Supply disruption	A cable strike can cut power to thousands of homes and critical facilities — the consequences extend far beyond the site.

Do

Don't

Obtain electricity cable records from the distribution network operator before excavating.
Scan the full dig area with a CAT and Genny in all modes before starting.
Hand dig within 500mm either side of any known or detected electricity cable.
Use insulated hand tools when excavating near known electricity cable positions.
Look for warning tiles, coloured tape, and duct runs during excavation.
Treat all unknown ducts as potentially containing live electricity cables.
Support exposed cables immediately to prevent damage from ground movement.
Brief all excavation workers on cable locations and strike emergency procedures.
Keep the network operator's emergency number readily available on site.
Report any cable damage, however minor, to the network operator immediately.

DON'T excavate without obtaining electricity cable records and completing a CAT scan.
DON'T machine dig within 500mm of a known or detected electricity cable.
DON'T use metal hand tools near electricity cables — use insulated digging equipment.
DON'T assume the absence of warning tape means no cable is present below.
DON'T open or investigate unknown ducts — they may contain live high voltage cables.
DON'T leave exposed cables unsupported — they must be protected from movement and damage.
DON'T start excavation near cables without briefing the team on emergency procedures.
DON'T touch a damaged cable — isolate the area and call the network operator.
DON'T backfill around exposed cables without the correct surround and protection.
DON'T continue digging if you see coloured ducting — stop and investigate cautiously.

See also: CAT & Genny Safe Use | Service Strike Emergency Procedure

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