Underground Construction (Tunneling)
Construction · Ver en español
Talking points
- Check for hazardous gases before entry and continuously during work. Oxygen must be at least 19.5%, and H₂S action level in tunnels is 5 ppm.
- An emergency escape plan must be established, communicated, and drilled. Every worker must know the primary and secondary escape routes.
- Fire-resistant hydraulic fluid must be used in hydraulically powered underground equipment unless the machine is protected by a fire-suppression system or a properly rated fire extinguisher. A hydraulic line burst with standard fluid in an enclosed space creates an immediate fire risk.
- Ground support and ventilation systems must be inspected regularly by a competent person. Changing ground conditions require reassessment.
- Communication systems must be maintained between the surface and the underground work area at all times.
Ask the crew
Can everyone identify the emergency exits and communication points in our underground work area?
Standards this talk is built on
A toolbox talk is a short safety briefing. It supports the training a standard requires; it does not replace it.
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Sign-in sheet
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| Name | Signature | Date |
|---|---|---|
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