Tunnel Working (Rail)

Toolbox Talk Record

Ref: TBT-RAI-016  |  Issue: 1  |  Date: March 2026
PresenterProject
LocationDate

What?

Why?

Prevent fatalitiesWorkers have been killed in rail tunnels by trains, electrocution, and toxic atmospheres. Strict controls are essential.
Legal complianceRailway-specific regulations and Network Rail standards impose strict duties for tunnel working activities.
Rescue capabilityLimited access and long evacuation distances in tunnels mean on-site rescue plans must be rehearsed.
Health protectionDiesel fumes, dust, and poor ventilation in tunnels cause respiratory harm without proper controls.
Do Don't
  • Ensure all personnel hold valid PTS and tunnel-specific safety briefing certification
  • Identify and brief all workers on positions of safety and refuge locations before entry
  • Confirm the possession is in place and track isolation verified before entering the tunnel
  • Carry personal gas monitors to detect oxygen depletion and toxic gas build-up
  • Maintain continuous communication between tunnel teams and the COSS at all times
  • Carry a personal torch and check emergency lighting is operational before entry
  • Wear appropriate RPE where diesel fume or dust exposure cannot be eliminated
  • Follow the agreed evacuation plan immediately if an emergency alarm is raised
  • Check ventilation fans are operational before and throughout the working period
  • Confirm OLE isolation or third rail discharge before working near electrified track
  • DON'T enter a rail tunnel without confirmed possession and track isolation
  • DON'T remove or switch off personal gas monitors while inside the tunnel
  • DON'T work beyond the agreed time limit for the possession in the tunnel
  • DON'T block emergency evacuation routes with materials, plant, or equipment
  • DON'T assume the tunnel atmosphere is safe — monitor continuously throughout
  • DON'T approach OLE or third rail unless confirmed isolated and earthed
  • DON'T rely solely on hearing for train warnings — noise levels mask signals
  • DON'T enter without knowing the location of all positions of safety and refuges
  • DON'T use petrol-powered equipment inside tunnels due to carbon monoxide risk
  • DON'T work alone or out of sight of other team members inside a rail tunnel

See also: Rail Safety Awareness | Overhead Line Equipment (OLE) Safety