Which statement about Class 3 flashpoints is true?

Which statement about Class 3 flashpoints is true?

• A. USA flashpoint ≤200°F is true
• B. UN flashpoint ≤200°F is true
• C. USA flashpoint ≤141°F is true
• D. UN flashpoint ≤212°F is true

Answer: (A)

Understanding how Class 3 liquids are defined hinges on flash point: the lowest temperature at which a liquid’s vapors can ignite in air. In the United States, Class 3 includes flammable liquids and, separately, combustible liquids, with an overall upper limit for Class 3 materials set at a flash point of 200°F (about 93°C). That means a liquid with a flash point at or below 200°F can be classified as a Class 3 material in the US system. Internationally (the UN system), the boundary is different: Class 3 liquids are defined by a flash point not exceeding 60°C (140°F). So the UN threshold is lower than the US threshold. Therefore, the statement about the USA having a flash point limit of ≤200°F is true because it matches the US classification rule. The other statements don’t fit because the UN threshold is not ≤200°F (it’s ≤140°F), and the US threshold isn’t limited to ≤141°F, since liquids up to 200°F can still be Class 3 in the US system. The UN threshold isn’t ≤212°F (100°C) either.

Understanding how Class 3 liquids are defined hinges on flash point: the lowest temperature at which a liquid’s vapors can ignite in air. In the United States, Class 3 includes flammable liquids and, separately, combustible liquids, with an overall upper limit for Class 3 materials set at a flash point of 200°F (about 93°C). That means a liquid with a flash point at or below 200°F can be classified as a Class 3 material in the US system.

Internationally (the UN system), the boundary is different: Class 3 liquids are defined by a flash point not exceeding 60°C (140°F). So the UN threshold is lower than the US threshold.

Therefore, the statement about the USA having a flash point limit of ≤200°F is true because it matches the US classification rule. The other statements don’t fit because the UN threshold is not ≤200°F (it’s ≤140°F), and the US threshold isn’t limited to ≤141°F, since liquids up to 200°F can still be Class 3 in the US system. The UN threshold isn’t ≤212°F (100°C) either.