Interpreting Expected Surface Fire Behavior

Once estimates of Rate of Spread and Flame Length have been obtained, use these classifications to evaluate the level of concern they generate.

Fire Behavior ClassRate of Spread (ch/hr)Flame Length (ft)Tactical Interpretation
Very Low0-20-1Direct, Hand
Low2-51-4Direct, Hand
Moderate5-204-8Direct, Equip
High20-508-12Indirect
Very High50-15012-25Indirect
Extreme150+25+Indirect

Surface Fire Behavior Characteristics Chart provides means for classifying and comparing individual fire events using spread rate and flame length (Fireline Intensity) or Heat per Unit Area.

 

Page Last Modified / Reviewed: 
2018-09-25