A term used to classify certain liquids that will burn on the basis of flash points. The National Fire Protection Association (NFPA) defines a combustible liquid as any liquid that has a closed-cup flash point above 100 degF (37.8 degC) (NFPA 30). There are three subclasses, as follows; Class II liquids have flash points at or above 100 degF (37.8 degC) but below 140 degF (60 degC). Class III liquids are subdivided into two additional subclasses; Class IIIA: Those having flash points at or above 140 degF (60 degC) but below 200 degF (93.4 degC), Class IIIB: Those having flash points at or above 200 degF (93.4 degC). The Department of Transportation (DOT) defines degcombustible liquids deg as those having flash points above 140 degF (60.5 degC) and below 200 degF (93.4 degC).
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