Demolition Near Live Services

Live services including gas, electricity, water, telecoms, and sewers may run through or adjacent to demolition sites.
Striking a live gas main during demolition can cause explosion, fire, and fatalities on the site and beyond.
High voltage electricity cables within or beneath demolition structures carry lethal voltages at all times.
A full services survey and utility disconnection plan must be completed before any demolition work starts.
Not all services can be disconnected before demolition — some must remain live to serve adjacent properties.
Services shown on record plans may not match actual positions — verification on site is essential.
HSG47 guidance on avoiding underground services applies fully to all demolition excavation and breaking work.
Overhead power lines adjacent to demolition sites create electrocution risk from crane jibs and falling structures.
Water mains struck during demolition cause flooding, undermining, and loss of supply to surrounding areas.
The pre-demolition survey must identify all services and specify isolation, protection, or diversion methods.

Prevent explosion	Striking a live gas main causes explosion and fire that can kill workers and members of the public nearby.
Electrocution risk	Contact with live HV cables during demolition is nearly always fatal — identification and isolation are critical.
Service continuity	Damaging live services to adjacent properties causes supply loss, flooding, and significant public disruption.

Do

Don't

Complete a full services survey before demolition and identify all live services on and near the site
Arrange disconnection of all services that can be isolated before demolition work begins
Mark the positions of all live services that must remain operational during demolition work
Use CAT and Genny detection and hand digging to confirm service positions near demolition areas
Brief all operatives on the location of live services and the emergency procedures for strikes
Maintain safe clearance distances from overhead power lines for all cranes and tall plant
Protect live services that cannot be disconnected with physical barriers and marker posts
Contact the utility company emergency number immediately if any live service is struck
Monitor for gas leaks using portable gas detectors when demolishing near gas infrastructure
Include service protection and isolation details in the demolition method statement

DON'T start demolition without a complete services survey and isolation plan in place
DON'T assume all services have been disconnected without verification on the day of work
DON'T use mechanical breakers near live electricity cables — hand dig within the safe zone
DON'T allow crane jibs or falling debris to encroach on overhead power line clearance zones
DON'T ignore the smell of gas during demolition — evacuate and call the gas emergency number
DON'T demolish structures containing live services without confirming their exact positions
DON'T remove service protection barriers to improve access for demolition plant
DON'T rely solely on record plans for service positions — verify on site with detection equipment
DON'T attempt to repair struck live services yourself — call the utility company immediately
DON'T store demolition materials on or near the marked positions of live buried services

See also: Demolition Safety Awareness | Service Strike Emergency Procedure

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