What does 'flammability' refer to in fire science?

Flammability specifically refers to the ability of a material to ignite and sustain combustion when exposed to a heat source. It is a critical concept in fire science as it informs safety practices, material selection, and fire prevention strategies. Understanding flammability allows fire engineers and safety professionals to evaluate the risks associated with different materials in environments where fire hazards may be present.

In considering the other options, the ability of a material to resist heat relates more closely to thermal resistance or insulation properties rather than flammability. The rate at which a material cools pertains to thermal dynamics and heat transfer rather than its capacity to burn. Density describes the mass of a material per unit volume and does not directly relate to its ignitability or burning characteristics. Thus, these concepts, while important in fire science, do not define flammability as accurately as the concept of a material's capability to ignite and burn.