FIGHTING WILDFIRES
California Fire Fighter
Joint Apprenticeship Committee
Topic: Causes of Entrapments
Causes of Entrapments
Entrapments
Unit Objectives
• Describe
• Firefighter entrapments
• Common causes of entrapments
• Unique hazards leading to structure protection
entrapments
• Common Denominators of Fire Behavior on
Tragedy Fires
Module 3 Safety and Survival
Page 1
FIGHTING WILDFIRES
California Fire Fighter
Joint Apprenticeship Committee
Topic: Causes of Entrapments
Entrapments
• Firefighters caught because of unexpected Fire
Behavior
• Most often occurs during
• High risk tactics
• Hasty tactical decisions
• High tempo operations
Entrapment Causes
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Failure to recognize problem Fire Behavior
Inadequate Safety Zone
Fuel between you and the fire
Hasty tactical decisions
Inadequate escape plan
Failure to Recognize
Problem Fire Behavior
• Fire Behavior appears
innocuous
• Complacency
• Failure to predict
change in fire
environment
• Underestimating fire
intensity or ROS
Module 3 Safety and Survival
Page 2
FIGHTING WILDFIRES
California Fire Fighter
Joint Apprenticeship Committee
Topic: Causes of Entrapments
Inadequate Safety Zones
• Inadequate Black
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In an area exposed to convection
Underslung line
Downhill
Reburn
Too small
A
Residual heat
B
Inadequate Safety Zones
• Too small
• Less than four times potential flame length
Inadequate Safety Zones
• In an area exposed to
convection
• Steep slope
• Chutes
• Ridge tops under Foehn winds
Module 3 Safety and Survival
Page 3
FIGHTING WILDFIRES
California Fire Fighter
Joint Apprenticeship Committee
Topic: Causes of Entrapments
Fuel Between You and the Fire
• Change direction/intensity
• Can cut off escape route
Hasty Tactical Decisions
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Escape fires
Structure threats
High tempo operations
Lack of risk assessment
Inadequate Escape Plan
• Warning too late
• Inadequate lookouts
• Inadequate communication
• Route too long or difficult
• Fatigue factors
• Steepness
• Distance
Module 3 Safety and Survival
Page 4
FIGHTING WILDFIRES
California Fire Fighter
Joint Apprenticeship Committee
Topic: Causes of Entrapments
High Risk Tactics
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Rescue
Downhill lines
Underslung lines
Spot fires
Indirect tactics
Firing operations
Frontal assault
Structure protection
High Risk Tactics
• Downhill
• Line construction
• Progressive hose lays
• Green below position on
hillside
• Adjacent Black exposed
to convection
High Risk Tactics
• Underslung Line (USL)
• Similar hazards to downhill
• Can become USL when working up hill
A
B
Module 3 Safety and Survival
Page 5
FIGHTING WILDFIRES
California Fire Fighter
Joint Apprenticeship Committee
Topic: Causes of Entrapments
High Risk Tactics
• Spot Fires
• May require travel through The Green
• Black usually too small
High Risk Tactics
• Indirect tactics
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Fuel between you and fire
Inadequate time for escape
Often involves firing tactics
Most roads are not adequate Safety Zones
High Risk Tactics
• Firing tactics
• Similar hazards as
indirect tactics
• Adds new hazards
• May change path of
main fire
• Often used in high
tempo operations
• May be uncoordinated
Module 3 Safety and Survival
Page 6
FIGHTING WILDFIRES
California Fire Fighter
Joint Apprenticeship Committee
Topic: Causes of Entrapments
High Risk Tactics
• Frontal assault
• Head attack
• Requires travel through The Green
• Often ordered in high tempo operations
High Risk Tactics
• Structure protection
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May include rescue operations
Fuel between you an the fire
Requires travel through The Green
Fire is often below you
Marginal Safety Zones
High Risk Tactics
• Rescue
• May need to seek refuge to protect people
• May need to accept extreme risk
• Extreme fire conditions
Module 3 Safety and Survival
Page 7
FIGHTING WILDFIRES
California Fire Fighter
Joint Apprenticeship Committee
Topic: Causes of Entrapments
Common Denominators of
Fire Behavior on Tragedy Fires
• Common Fire Behavior causes of entrapments
• Usually a sudden change in Fire Behavior
• Firefighters were surprised
• Better analysis of potential Fire Behavior can
reduce probability of surprises
Four Common Denominators
1. On relatively small fires or deceptively quiet
areas of large fires
2. In relatively light fuels such as grass, herbs and
light brush
3. With unexpected shifts in wind direction or
wind speed
4. When fire responds to topographic conditions
and runs uphill
Four Common Denominators
1. Relatively small fires or
deceptively quiet areas of large
fires
• Low intensity fire seems safe
• Fire Behavior factors create
potential for sudden change
• Flawed Situation Awareness (SA)
causes complacency
Module 3 Safety and Survival
Page 8
FIGHTING WILDFIRES
California Fire Fighter
Joint Apprenticeship Committee
Topic: Causes of Entrapments
Four Common Denominators
2. Relatively light fuels
• Light fuels on steep slopes
can have extreme ROS
• Spot fire or slope reversal
can add unexpected new
threat
Four Common Denominators
3. Unexpected shifts in wind direction or wind
speed
• Topography/local weather can cause wind shifts
• Weather and strong columns can cause downdown-drafts
• Sudden wind changes can compromise escape
routes
Four Common Denominators
4. Fire responds to topographic conditions and
runs uphill
• Chimneys and gullies affect direction and ROS
• Surprisingly fast in chimneys, gullies and on steep slopes
• Firefighters on slopes and in saddles are surprised
by intensity and ROS
Module 3 Safety and Survival
Page 9
FIGHTING WILDFIRES
California Fire Fighter
Joint Apprenticeship Committee
Topic: Causes of Entrapments
Summary
• Several factors may lead to entrapment
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Sudden changes in Fire Behavior
Topographic influence on Fire Behavior
Inadequate escape plans
High risk tactics
Rescue operations
• Recognizing entrapment causes is key to safety
and survival
Module 3 Safety and Survival
Page 10