Flame Spread Index
A numerical designation, applied to a building material, which is a comparative measure of the ability of the material to resist flaming combustion over its surface.
ASTM E84, commonly known as the 25-foot tunnel test, measures the rate of flame travel:
- selected species of untreated lumber has a designated value of 100
- noncombustible inorganic reinforced cement board has a value of 0
ASTM E84 Standard Test Method for Surface Burning Characteristics of Building Materials
See also: Smoke Developed.
Subjects: Civil Engineering