Editing Flash point (section)

== Mechanism ==
All [[liquid]]s have a specific [[vapor pressure]], which is a [[function (mathematics)|function]] of that liquid's [[temperature]] and is subject to [[Boyle's law|Boyle–Mariotte law]]. As temperature increases, vapor pressure increases. As vapor pressure increases, the concentration of vapor of a flammable or combustible liquid in the air increases. Hence, temperature determines the concentration of vapor of the flammable liquid in the air. A certain concentration of a flammable or combustible vapor is necessary to sustain combustion in air, the [[lower flammable limit]], and that concentration is specific to each flammable or combustible liquid. The flash point is the lowest temperature at which there will be enough flammable vapor to support combustion when an ignition source is applied.