Introduction to FuelModels S 390 classroom module

Introduction to the 40
Fire Behavior Fuel
Models

Three-part naming
convention used for the 40
Fire Behavior Fuel Models
1. Fuel model code
NB
GR
GS
SH
TU
TL
(Non- (Gras (Gra (Shru (Timber
(Timber
burnab s)
ssb)
Understo Litter)
le)
Shru

ry)
b)

SB
(Slash
Blowdo
wn)

NB1

GR1

GS1

SH1

TU1

TL1


SB1

NB2

GR2

GS2

SH2

TU2

TL2

SB2

NB3

GR3


GS3

SH3

TU3

TL3

SB3

NB8

GR4

GS4

SH4

TU4


TL4

SB4

NB9

GR5

SH5

TU5

TL5

GR6

SH6

TL6


GR7

SH7

TL7

GR8

SH8

TL8

Three-part naming convention
used for the
40 Fire Behavior Fuel Models
1. Fuel model code
2. Fuel model number
Fuel Type

Fuel Model

Number
Block

Used in
original or
new set

1-13

1-13

Reserved
for future
standard
fuel
models

14-89

Available

for custom
fuel
models

14-89

NB

90-99

91-93, 98-99 94-95

90,96-97

GR

100-119

101-109


110-112

100,113-119

GS

120-139

121-124

125-130

120-131-139

SH

140-159

141-149


150-152

140,153-159

TU

160-179

161-165

166-170

160,171-179

TL

180-199

181-189


190-192

180, 193199

SB

200-219

201-204

205-210

200, 211219

Three-part naming convention
used for the
40 Fire Behavior Fuel Models
1. Fuel model code
2. Fuel model number
Fuel Type


Fuel Model
Number
Block

Used in
original or
new set

1-13

1-13

Reserved
for future
standard
fuel
models

14-89

Available
for custom
fuel
models

14-89

NB

90-99

91-93, 98-99 94-95

90,96-97

GR

100-119

101-109

110-112

100,113-119

GS

120-139

121-124

125-130

120-131-139

SH

140-159

141-149

150-152

140,153-159

TU

160-179

161-165

166-170

160,171-179

TL

180-199

181-189

190-192

180, 193199

SB

200-219

201-204

205-210

200, 211219

Three-part naming convention
used for the
40 Fire Behavior Fuel Models
1. Fuel model code
2. Fuel model number
Fuel Type

Fuel Model
Number
Block

Used in
original or
new set

1-13

1-13

Reserved
for future
standard
fuel
models

14-89

Available
for custom
fuel
models

14-89

NB

90-99

91-93, 98-99 94-95

90,96-97

GR

100-119

101-109

110-112

100,113-119

GS

120-139

121-124

125-130

120-131-139

SH

140-159

141-149

150-152

140,153-159

TU

160-179

161-165

166-170

160,171-179

TL

180-199

181-189

190-192

180, 193199

SB

200-219

201-204

205-210

200, 211219

Three-part naming convention
used for the
40 Fire Behavior Fuel Models
1. Fuel model code
2. Fuel model number
Fuel Type

Fuel Model
Number
Block

Used in
original or
new set

1-13

1-13

Reserved
for future
standard
fuel
models

14-89

Available
for custom
fuel
models

14-89

NB

90-99

91-93, 98-99 94-95

90,96-97

GR

100-119

101-109

110-112

100,113-119

GS

120-139

121-124

125-130

120-131-139

SH

140-159

141-149

150-152

140,153-159

TU

160-179

161-165

166-170

160,171-179

TL

180-199

181-189

190-192

180, 193199

SB

200-219

201-204

205-210

200, 211219

Three-part naming convention
used for the
40 Fire Behavior Fuel Models
1. Fuel model code
2. Fuel model number
Fuel Type

Fuel Model
Number
Block

Used in
original or
new set

1-13

1-13

Reserved
for future
standard
fuel
models

14-89

Available
for custom
fuel
models

14-89

NB

90-99

91-93, 98-99 94-95

90,96-97

GR

100-119

101-109

110-112

100,113-119

GS

120-139

121-124

125-130

120-131-139

SH

140-159

141-149

150-152

140,153-159

TU

160-179

161-165

166-170

160,171-179

TL

180-199

181-189

190-192

180, 193199

SB

200-219

201-204

205-210

200, 211219

Three-part naming convention
used for the
40 Fire Behavior Fuel Models
1. Fuel model code
2. Fuel model number
Fuel Type

Fuel Model
Number
Block

Used in
original or
new set

1-13

1-13

Reserved
for future
standard
fuel
models

14-89

Available
for custom
fuel
models

14-89

NB

90-99

91-93, 98-99 94-95

90,96-97

GR

100-119

101-109

110-112

100,113-119

GS

120-139

121-124

125-130

120-131-139

SH

140-159

141-149

150-152

140,153-159

TU

160-179

161-165

166-170

160,171-179

TL

180-199

181-189

190-192

180, 193199

SB

200-219

201-204

205-210

200, 211219

Example of how fuel model code and
fuel model number are applied in a
real-world scenario

Three-part naming convention used for the
40 Fire Behavior Fuel Models
1. Fuel model Code
2. Fuel model Number
3. Fuel Model Name

Example of Fuel Model Code, Number and Name from the
Scott and Burgan publication (GTR-153)
Fuel Model
Code

Fuel Model
Number



Dynamic fuel
models
Allocation
of herbaceous
load to live and dead

Dynamic fuel
models

Dynamic fuel
models

0.
5

7
5

Dynamic fuel models

0.67



Dynamic fuel
models
Allocation
of herbaceous

load to live and dead
• Dead herbaceous load
takes on dead 1-hr MC



Dynamic fuel
models
Allocation
of herbaceous

load to live and dead
• Dead herbaceous load
takes on dead 1-hr MC
• Increases ability (and
difficulty)

Let’s look at the Fuel Model codes used in
the 40 Fire Behavior Fuel Model naming
convention

Non-burnable Fuel Type Models (NB)
In all non-burnable fuel models there is no fuel load – wildland fire will
not spread. These NB fuel models were developed to provide
consistency in how the non-burnable portions of the landscape are
displayed on a fuel model map.
NB1 = Urban
Developed
NB2 = Snow/Ice
NB3 =
Agricultural
NB8 = Open
Water
NB9 = Bare
Ground

Grass Fuel Type Models (GR)
The primary carrier of fire in the GR fuel models is grass.
Fire behavior varies from moderate spread rate and low
flame length in the sparse grass to extreme spread rate and
flame length in the tall grass models. Fuel bed depth may
range between 1 foot and 2.5 feet deep.

GR1 = Short, Sparse Dry Climate Grass
(Dynamic)
GR2 = Low Load, Dry Climate Grass
(Dynamic)
GR3 = Low Load, Very Coarse, Humid Climate
Grass (Dynamic)
GR4 = Moderate Load, Dry Climate Grass
(Dynamic)
GR5 = Low Load, Humid Climate Grass
(Dynamic)

Grass-Shrub Fuel Type Models (GS)
The primary carrier of fire in the GS fuel models is grass
and shrubs combined; both components are important in
determining fire behavior. The effect of live fuels and their
current moisture content on spread rate and intensity is
strong and depends on the relative amount of grass and
shrub load in the fuel model.

GS1 – Low Load, Dry Climate Grass-Shrub
(Dynamic)
GS2 – Moderate Load, Dry Climate GrassShrub (Dynamic)

Shrub Fuel Type Models (SH)
The primary carrier of fire in the SH fuel models is live and dead shrub twigs
and foliage in combination with dead and down shrub litter. A small amount
of herbaceous fuel may be present, especially in SH1 and SH9. The effect of
live herbaceous moisture content on spread rate and flame length can be
strong in the dynamic SH models.
SH1 – Low Load, Dry Climate Shrub
(Dynamic)
SH2 – Moderate, Load Dry Climate
Shrub
SH3 – Moderate Load, Humid Climate
Shrub
SH4 – Low Load, Humid Climate TimberShrub
SH5 – High Load, Dry Climate Shrub
SH6 – Low Load, Humid Climate Shrub
SH7 – Very High Load, Dry Climate
Shrub
SH8 – High Load, Humid Climate Shrub
SH9 – Very High Load, Humid Climate
Shrub (Dynamic)

Timber-Understory Fuel Type Models (TU)
Primary carrier of fire in the TU fuel models is forest litter in combination
with herbaceous or shrub fuels. TU1 and TU3 contain live herbaceous load
and are dynamic.
TU1 – Low Load Dry Climate Timber-Grass-Shrub
(Dynamic)
TU2 – Moderate Load, Humid Climate TimberShrub
TU3 – Moderate Load, Humid Climate TimberGrass-Shrub (Dynamic)
TU4 – Dwarf Conifer with Understory
TU5 – Very High Load, Dry Climate Timber-Shrub

Timber Litter Fuel Type Models (TL)
The primary carrier of fire in the TL fuel models
is dead and down woody fuel. Live fuel, if
present, has little effect on fire behavior.

TL1 – Low Load Compact
Conifer Litter
TL2 – Low Load Broadleaf
Litter
TL3 – Moderate Load Conifer
Litter
TL4 – Small Downed Logs
TL5 – High Load Conifer
Litter
TL6 – Moderate Load
Broadleaf Litter
TL7 – Large Downed Logs
TL8 – Long-Needle Litter
TL9 – Very High Load
Broadleaf Litter

Slash-Blowdown Fuel Type Models
The primary carrier of(SB)
fire in the SB fuel models is

activity fuel or blowdown. Forested areas with heavy
mortality may be modeled with SB fuel models.

SB1 – Low Load Activity Fuel
SB2 – Moderate Load Activity Fuel or Low
Load Blowdown
SB3 – High Load Activity Fuel or Moderate
Load Blowdown
SB4 – High Load Blowdown

Helpful Tools

Helpful Tools
• GTR-153
– Photos, descriptions, selection guide,
crosswalk, fire behavior charts
– Electronic and printed formats
• http://www.frames.gov

http://www.frames.gov/subject-areas/fuels/

Helpful Tools
• GTR-153
• Help file
– Searchable, hyperlinked
– GTR-153 content included
– Comprehensive fire behavior charts
– Available at FRAMES

Helpful Tools
• Printed GTR
• Help file
• Comparison spreadsheet

Two-step process
• Initial selection
– Selection guide
– Crosswalk
– Rule/algorithm
– Experience

Two-step process
• Initial selection
– Selection guide
– Crosswalk
– Rule/algorithm
– Experience

• Fire behavior simulation
– Confirm final selection

Now we’ll work through some examples of various
fuel models.
(Note - Trying to focus on and be similar to the classroom module in 390
that already exists for the 13 fuel models – showing picture examples as
well as short video fire behavior examples (to be included at a later date), of
the fuel model groups.)

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