Live services
Underground and overhead services
Electricity, gas, water, telecoms and drainage in the ground or overhead, which must be located, marked and treated as live before any excavation or work near them.
Striking a buried electricity cable or gas main is one of the most dangerous things that happens on a site, and it happens because someone assumed. The HSE's guidance HSG47 sets the sequence: obtain the utility plans, understanding that they are indicative; survey the area with a cable avoidance tool and a signal generator, by a trained operator, marking the ground; hand-dig trial holes to confirm the position and depth of every marked service before machine excavation near it; and treat every service as live until the owner confirms otherwise. Overhead lines get goalposts, bunting and exclusion zones sized to the voltage, and a written agreement with the network operator where plant will work near them.
The permit-to-work process for excavation and breaking ground turns this into a checklist the issuer confirms before the first bucket. Safe digging practice near a located service means hand tools, no picks or forks driven into the ground, and a spotter. If a service is struck, the response is to stop, get everyone clear, not touch it, and call the owner's emergency line; a damaged gas main or cable is reported as a dangerous occurrence under RIDDOR where the criteria are met.
Where it comes from
- Construction (Design and Management) Regulations 2015 reg.25: energy distribution installations.
- Electricity at Work Regulations 1989 reg.4 and reg.14.
- HSE guidance HSG47 (Avoiding danger from underground services) and GS6 (Avoiding danger from overhead power lines).
Questions people ask
The plans show nothing in the area. Can we dig?
After a CAT and Genny sweep by a trained operator and trial holes where the sweep finds anything, yes, with care. Plans are indicative; services move, get added and get mis-recorded. The sweep and the trial hole are the controls, not the plan.
Who can use a CAT and Genny?
Someone trained in it. Used in one mode only, without the signal generator, or by someone who does not understand what it cannot detect (plastic pipes, deep services, unpowered cables), it gives false confidence.
Live services, handled on a phone
SiteLynx puts the RAMS, permits, inspections, audits, plant checks and records behind every term in this glossary on the crew's phones, signed on site, with a PDF at the end. 14 days free, no card.
Start free trial