Which description corresponds to 5.2 Type D materials?

• A. Detonates only partially or deflagrates slowly, with medium to no effect when heated under confinement.
• B. Can detonate or deflagrate rapidly as packaged for transport.
• C. Neither detonates nor deflagrates rapidly and cannot undergo thermal explosion.
• D. Neither detonates nor deflagrates rapidly, but that can undergo a thermal explosion.

Answer: (A)

Type D materials in the 5.2 category are characterized by limited explosive behavior: they may detonate only partially or deflagrate slowly, and heating them under confinement tends to produce only a medium to no effect. This means they’re not prone to rapid, full-scale detonation, but they aren’t completely nonhazardous either. The description you’re looking for captures that nuanced behavior, where the energy release is limited and may be followed by slow burning or partial detonation, especially when confinement changes the reaction dynamics. The other descriptions describe materials that are either more reactive (detonating or deflagrating rapidly) or effectively nonreactive (neither detonating nor deflagrating rapidly and unable to undergo thermal explosion), which doesn’t fit Type D's typical pattern.