Flammable Liquids

Any liquid that has a closed-cup flash point below 100ºF (37.8ºC), as determined by the test procedures described in NFPA 30 and a Reid vapor pressure not exceeding 40 psia (2068.6 mm Hg) at 100ºF (37.8ºC), as determined by ASTM D 323, Standard Method of Test for Vapor Pressure of Petroleum Products (Reid Method). Flammable liquids are classified as Class I as follows:

  • Class IA liquids shall include those liquids that have flash points below 73ºF (22.8ºC) and boiling points below 100ºF (37.8ºC).
  • Class IB liquids shall include those liquids that have flash points below 73ºF (22.8ºC) and boiling points at or above 100ºF (37.8ºC).
  • Class IC liquids shall include those liquids that have flash points at or above 73ºF (22.8ºC), but below 100ºF (37.8ºC).

(NFPA 30)