Combustion, n — a chemical process of oxidation that occurs at a rate fast enough to produce temperature rise and glow or flame.
Combustible, adj — capable of undergoing combustion. Combustible is a relative term; many materials that undergo combustion under one set of conditions will not combust under others, e.g., steel is non-combustible but when shaved into very fine steel wool will combust. The term combustible does not indicate ease of ignition, burning intensity, or rate of burning except when modified by a word such as highly, as in highly combustible.
Fire, n — destructive burning as manifested by any or all of the following: light, flame, heat, smoke.
Fire proof (flame proof), n — inappropriate and misleading terms
Fire resistance, n — the property of a material or assemblage to withstand fire or give protection from it.
Flame (Fire) retardant chemical, n — a chemical, which when added to a combustible material, delays ignition and combustion of the resulting material when exposed to fire.
Flame (Fire) retardant coating, n — a liquid applied surface covering on a combustible material which delays ignition and combustion of the material when the coating is exposed to fire.
Intumescent Flame (Fire) retardant coating, n — a liquid applied surface covering on a combustible material which delays ignition and combustion by expanding when exposed to fire.
Flame, n — a hot usually luminous zone of gas that is undergoing combustion.
Flame spread index, n — a number or classification based on a calculated value derived from observations made under defined test conditions.
Flammable, n — a combustible material that ignites easily and burns intensely.
Flashover, n — the rapid transition to a state of total surface involvement in a fire of combustible materials within an enclosure.
Ignition, n — the initiation of combustion.
Optical smoke density, n — a defined unit of smoke intensity related to percent light transmission
Smoke toxicity, n — the propensity of smoke to produce adverse biochemical or physiological effects.