What does the term flash point refer to?

The term flash point specifically refers to the minimum temperature at which a liquid's vapors will ignite when an ignition source is present. This measurement is critical in fire safety and hazard assessment because it helps determine the flammability of a substance. Substances with a lower flash point pose a greater risk for ignition, especially in environments where heat sources are present.

In fire investigations, understanding the flash point of materials involved can significantly assist in identifying potential fire causes and preventing future incidents. The flash point does not indicate when a liquid boils, as indicated by the first option, nor does it refer to the temperature at which a substance spontaneously ignites, which is characterized by the ignition temperature. Additionally, the term does not pertain to a gas becoming flammable; rather, it specifically applies to liquids and their ability to produce ignitable vapors under controlled conditions. Therefore, option B accurately captures the definition and significance of flash point in the context of fire investigation and safety.