Flammable liquids correspond to which DOT Class?

• A. DOT Class 1
• B. DOT Class 2
• C. DOT Class 3
• D. DOT Class 4

Answer: (C)

Flammable liquids are grouped into DOT Class 3. This class includes liquids that can ignite at relatively low temperatures, defined by a flash point at or below 60°C (140°F). That makes them the “liquid” counterpart to the hazmat category for flammability. Examples you’ll often see in this class are gasoline and acetone, which readily form ignitable vapors in typical conditions.

The other classes cover different hazards: Class 1 is explosives, Class 2 covers gases, and Class 4 includes flammable solids (and materials that can ignite or burn rapidly as solids). Remembering that Class 3 is specifically about liquids that burn easily helps you place flammable liquids correctly.