Underground and Overhead Services
Plans, locating, trial holes, safe digging, exclusion and emergency action around electricity, gas and other services.
How to prepare for a CITB Specialist test
Lock in common site safety first, confirm the exact route with the card scheme, then add the relevant specialist hazards and competence boundaries.
Core concepts
Concept 1
Service plans are a starting point and must be combined with locating, marking, safe excavation methods and continuing observation.
Exam cue: Confirm the latest information, survey the area and positively mark detected routes before digging.
Concept 2
Overhead lines require planned clearance, access control and equipment restrictions because flashover can occur without contact.
Exam cue: Use hand tools and safe exposure methods as the plan requires near underground services.
Concept 3
Damage, contact, arcing or a suspected gas escape requires stopping work, keeping people away and using the site and utility emergency process.
Exam cue: Never approach plant touching a line or operate switches near a suspected gas release.
Risk pitfalls and guardrails
Assuming a drawing gives the exact depth and route.
Guardrail: Do not mix specialist routes or replace an engineered, competent control with a briefing, warning sign or PPE alone.
Using an excavator carefully as the only method of locating a cable.
Guardrail: Do not mix specialist routes or replace an engineered, competent control with a briefing, warning sign or PPE alone.
Touching a machine after overhead-line contact to help the operator.
Guardrail: Do not mix specialist routes or replace an engineered, competent control with a briefing, warning sign or PPE alone.
Memory anchors
Plans Plus Locate
Drawings alone do not prove the exact current position of a buried service.
Mark Before Break
Survey and mark the route before excavation or penetration begins.
Expose Carefully
Use the approved safe digging method and support exposed services.
Clearance Prevents Arc
Stay within planned limits because electricity can bridge a gap.
Contact? Keep Away
Do not approach affected plant until the supply owner confirms safety.
Gas Means No Spark
Stop work, avoid ignition and follow the emergency route.
Checkpoint rule
Do the check-up only after you can summarize each concept in one sentence and identify one dangerous pitfall from memory.
Knowledge Check (after reading)
Short check-up to confirm understanding of this module.
Check-up Questions
Next step personalized recommendations
Continue learning
Move forward only after this module is stable.
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