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Downhill Fireline Construction Checklist

 

Building fireline downhill requires special attention to safety factors because of the potential for rapid uphill fire spread. This Watch Out depicts firefighters building fireline downhill without first mitigating the existing hazards.

9. Building fireline downhill with fire below. Three firefighters use tools to dig fireline down a steep slope covered in grass and brush.  Large flames are below them as the fire burns uphill.

9. Building fireline downhill with fire below.

Read about all 18 Watch Out Situations.

 

Downhill fireline construction is hazardous in steep terrain, fast-burning fuels, or rapidly changing weather. Downhill fireline construction should not be attempted unless there is no tactical alternative. When building downhill fireline:

  • Crew supervisor(s) and fireline overhead must discuss assignments prior to committing personnel. Qualified, responsible overhead individuals such as a Task Force Leader (TFLD) or an Incident Commander Type 4 (ICT4) at minimum, will stay with resources until the job is completed.
  • Decisions about downhill fireline construction will be made only after proposed fireline has been scouted by supervisor(s) of involved crew(s).
  • Lookouts, Communications, Escape Routes, and Safety Zones (LCES) will be coordinated for all personnel involved. This includes verifying:
    • Crew supervisors are in direct contact with lookout(s) who can see the fire.
    • Communication is established between crews.
    • Rapid access to safety zones is ensured in case fire crosses below crews.
  • Direct attack will be used whenever possible; if not possible, the fireline should be completed between anchor points before being fired out.
  • Fireline will not lie in or adjacent to a chute or chimney.
  • Starting point will be anchored for crews building fireline down from the top.
  • Bottom of the fire will be monitored; if the potential exists for the fire to spread, action will be taken to secure the fire edge.
  • Before carrying fire with you, ensure it can be done safely.

 

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