Table 2 Variable equation table of the LR model

Fire front length (L)

  < 50 m

 − 1,056

1,136

0,348

 50–100 m

 − 1,782

1,092

0,168

 100–250 m

 − 1,781

1,081

0,168

 250–400 m

 − 3,114

1,145

0,044

 400–600 m

 − 2,939

1,211

0,053

 600–800 m

 − 2,324

1,247

0,098

 800–1000 m

 − 3,385

1,179

0,034

  > 1000 m

Fuel break type (PIT)

 Vegetation-free

3,192

1,174

24,330

 Combination of vegetation-free and vegetated

2,530

1,004

12,556

 Vegetated

Fuel break location (LOC)

 Steepest slope

0,887

0,721

2,429

 Flat

1,411

0,718

4,101

 Ridgeline

1,397

0,991

4,042

 Lower slope

0,318

0,711

1,375

 Mid-slope

1,320

0,919

3,745

 Canyon bottom

Fuel break width (W)

0,017

0,005

1,017

Intersection angle between fire and fuel break (ANG)

 Almost parallel

 − 1,202

0,545

0,301

 Lateral

 − 2,127

0,504

0,119

 Perpendicular

Type of suppression work executed on fuel break (SW)

 Combined ground-aerial firefighting

0,292

0,523

1,339

 Ground firefighting

 − 2,305

0,404

0,100

 Aerial firefighting

 − 3,479

0,485

0,031

 Fire spread with no suppression due to technical reasons

 − 21,396

4201,908

0,000

 Fire spread with no suppression due to safety reasons

Flame length (FL)

 − 0,536

0,104

0,585

Constant (b₀)

5,226

1,302

186,125