Flammable liquids are identified by which DOT placard class?

Flammable liquids are identified by which DOT placard class?

• A. Class 2
• B. Class 3
• C. Class 4
• D. Class 6

Answer: (B)

Hazard class designations on DOT placards identify the type of danger, and flammable liquids fall under Class 3. This classification exists because flammable liquids are defined by a flash point criterion—they ignite at relatively low temperatures—specifically below 60°C (140°F). The placard for this class features a flame symbol and the numeral 3, signaling responders that ignition risk is high and that special precautions around ignition sources, ventilation, and PPE are important during handling and in emergencies. This helps distinguish them from other hazards, such as gases (Class 2) or flammable solids (Class 4).

Hazard class designations on DOT placards identify the type of danger, and flammable liquids fall under Class 3. This classification exists because flammable liquids are defined by a flash point criterion—they ignite at relatively low temperatures—specifically below 60°C (140°F). The placard for this class features a flame symbol and the numeral 3, signaling responders that ignition risk is high and that special precautions around ignition sources, ventilation, and PPE are important during handling and in emergencies. This helps distinguish them from other hazards, such as gases (Class 2) or flammable solids (Class 4).