Any liquid that has a closed-cup flash point below 100 F (37.8 C), as determined by the test procedures described in NFPA 30 and a Reid vapor pressure not exceeding 40 psia (2068.6 mm Hg) at 100 F (37.8 C), as determined by ASTM D 323, Standard Method of Test for Vapor Pressure of Petroleum Products (Reid Method). Class IA liquids shall include those liquids that have flash points below 73 F (22.8 C) and boiling points below 100 F (37.8 C). Class IB liquids shall include those liquids that have flash points below 73 F (22.8 C) and boiling points at or above 100 F (37.8 C). Class IC liquids shall include those liquids that have flash points at or above 73 F (22.8 C), but below 100 F (37.8 C). (NFPA 30)
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