What is the USA Closed Cup Flashpoint for Class 3 HazMats?

• A. ≤141ºF
• B. ≤100ºF
• C. ≤212ºF
• D. ≤200ºF

Answer: (D)

In hazmat classification, the key idea is the temperature at which a liquid’s vapors can ignite in air—the flash point. For Class 3 flammable liquids in the United States, this value is determined using a closed-cup test (the Pensky-Martens method). If the closed-cup flash point is at or below about 140°F (60°C), the liquid is considered a Class 3 flammable liquid. Because test options are often rounded, the closest equivalent shown is around ≤141°F.

So, the reason this threshold matters is that it sets the cutoff for labeling, packaging, and shipping requirements for flammable liquids. The other numbers don’t fit the standard: 212°F is the boiling point of water and isn’t the classification cutoff; 200°F is above the 140°F limit; 100°F is below the limit but does not represent the maximum threshold used for Class 3 classification.