Flammable and Combustible Solvents

In contrast, a combustible liquid has a flash point at or above 100°F (37.8°C) (1910.106(a)(18)). The combustible liquids are divided into two classes  

According to 1910.106(a)(18)(ii)(b), class 3B liquids include those with flash points at or above 200°F (93.3°C). This section does not cover class 3B liquids. Where the term class 3 liquids is used in the section, it means only class 3A liquids. (Class 3B is used in this document for reference purposes only.) 

It should be noted that whenever a combustible liquid is heated for use to within 30°F (16.7°C) of its flash point, it should be handled in accordance with the requirements for the next lower class of liquids (1910.106(a)(18)(iii)). 

The flash point and boiling point determine the class of a liquid. However, these should not be the only criteria used to determine the hazards of a liquid. Many other factors should also be considered for the proper use and storage of hazardous liquids. These factors include ignition temperature, lower explosive limit (LEL) or upper explosive limit (UEL), vapor pressure, specihc gravity, and vapor density. 

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