Which statement correctly describes ordinary hazard materials?

Which statement correctly describes ordinary hazard materials?

• A. They have low combustibility and low heat release
• B. They have moderate combustibility and heat release
• C. They have high combustibility and heat release
• D. They have no combustibility

Answer: (B)

Ordinary hazard materials sit in the middle of fire risk categories because they burn with a moderate rate and release a moderate amount of heat. This means they’re capable of igniting under common fire conditions and contributing a noticeable amount of energy, but they don’t ignite as easily or produce as much heat as high-hazard fuels. They are more substantial than light-hazard materials (which have low combustibility and low heat release) and not as intense as high-hazard materials. Nonflammable substances would have no combustibility, which isn’t the case here. So describing ordinary hazard materials as having moderate combustibility and heat release best captures their mid-range fire behavior.

Ordinary hazard materials sit in the middle of fire risk categories because they burn with a moderate rate and release a moderate amount of heat. This means they’re capable of igniting under common fire conditions and contributing a noticeable amount of energy, but they don’t ignite as easily or produce as much heat as high-hazard fuels. They are more substantial than light-hazard materials (which have low combustibility and low heat release) and not as intense as high-hazard materials. Nonflammable substances would have no combustibility, which isn’t the case here. So describing ordinary hazard materials as having moderate combustibility and heat release best captures their mid-range fire behavior.