Which class includes liquids with flashpoints at or above 140°F (60°C) and below 200°F (93.3°C)?

Which class includes liquids with flashpoints at or above 140°F (60°C) and below 200°F (93.3°C)?

• A. Class II
• B. Class IIIA
• C. Class IIIB
• D. Class I

Answer: (B)

Understanding how flammable liquids are classified by flash point helps determine storage and handling requirements. The flash point is the lowest temperature at which enough vapor is produced to form an ignitable mixture with air. Liquids with lower flash points ignite more easily. Class I covers liquids with flashpoints below 100°F, Class II covers 100–139°F, Class III covers 140–199°F (split into IIIA and IIIB for subranges), and Class IIIB covers 200°F and above. Since the range 140°F to just under 200°F fits the 140–199°F window, it falls into Class IIIA.

Understanding how flammable liquids are classified by flash point helps determine storage and handling requirements. The flash point is the lowest temperature at which enough vapor is produced to form an ignitable mixture with air. Liquids with lower flash points ignite more easily. Class I covers liquids with flashpoints below 100°F, Class II covers 100–139°F, Class III covers 140–199°F (split into IIIA and IIIB for subranges), and Class IIIB covers 200°F and above. Since the range 140°F to just under 200°F fits the 140–199°F window, it falls into Class IIIA.