Which describes readily combustible solids?

Which describes readily combustible solids?

• A. Solids that are always water reactive.
• B. Materials that cause fire through friction, burn faster than 2.2 mm/sec, or any metal powder that can be ignited.
• C. Solids that ignite only when heated above 500 C.
• D. Solids that do not support combustion.

Answer: (B)

Readily combustible solids are those that can start burning easily under ordinary conditions, typically by friction, burn rapidly once ignited, or include metal powders that can be ignited. The description that adds ignition by friction, a rapid burning rate (faster than 2.2 mm/sec), or any metal powder that can be ignited matches this definition and captures the ways these materials can pose a fire risk. Solids that are only water reactive describe a different hazard class, not the readily combustible solids category. A solid that ignites only above a high temperature (like 500 C) isn’t readily ignitable, and a material that does not support combustion is the opposite of readily combustible.

Readily combustible solids are those that can start burning easily under ordinary conditions, typically by friction, burn rapidly once ignited, or include metal powders that can be ignited. The description that adds ignition by friction, a rapid burning rate (faster than 2.2 mm/sec), or any metal powder that can be ignited matches this definition and captures the ways these materials can pose a fire risk. Solids that are only water reactive describe a different hazard class, not the readily combustible solids category. A solid that ignites only above a high temperature (like 500 C) isn’t readily ignitable, and a material that does not support combustion is the opposite of readily combustible.