Which of the following is not listed as a defined fire class in the material?

• A. Class A fires (ordinary combustibles)
• B. Class B fires (flammable liquids)
• C. Class C fires (electrical)
• D. Class D fires (metals)

Answer: (D)

Fire classifications group fires by what is burning. In many safety materials, the main categories defined are ordinary combustibles, flammable liquids, and electrical fires. Metals, on the other hand, are often treated as a separate category because they require different extinguishing agents and handling. If your material only lists the first three categories, the metal-fire category would not be included in its defined set. That’s why the metal-fire option is the one not listed, making it the correct choice for this question. The other categories—ordinary combustibles, flammable liquids, and electrical—are the ones typically defined and included.