Within the UN/DOT classification system, a container labeled with a Hazard class of 4 contains a(n):

Within the UN/DOT classification system, a container labeled with a Hazard class of 4 contains a(n):

• A. Flammable liquid
• B. Flammable solid
• C. Gas
• D. Explosive solid

Answer: (B)

Hazard class numbers group dangerous goods into broad categories. Class 4 is Flammable Solids, which are materials that ignite readily and can burn vigorously, sometimes reacting with other substances to keep burning. So a container marked with this class is describing a flammable solid. It isn’t a flammable liquid (that’s Class 3), it isn’t a gas (that’s Class 2), and it isn’t an explosive solid (that’s Class 1). There are subcategories within Class 4 for special cases, like spontaneous combustion or water-reactive flammables, but the label 4 identifies flammable solids in general.

Hazard class numbers group dangerous goods into broad categories. Class 4 is Flammable Solids, which are materials that ignite readily and can burn vigorously, sometimes reacting with other substances to keep burning. So a container marked with this class is describing a flammable solid. It isn’t a flammable liquid (that’s Class 3), it isn’t a gas (that’s Class 2), and it isn’t an explosive solid (that’s Class 1). There are subcategories within Class 4 for special cases, like spontaneous combustion or water-reactive flammables, but the label 4 identifies flammable solids in general.