Which statement correctly describes 5.2 Type B materials?

• A. Can detonate or deflagrate rapidly as packaged for transport.
• B. Detonates only partially or deflagrates slowly, with medium to no effect when heated under confinement.
• 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: (D)

5.2 Type B materials are organic peroxides whose hazard comes from heat-driven decomposition rather than an immediate explosive reaction. They won’t detonate or burn rapidly just from being packaged for transport. However, if heat builds up, they can undergo a thermal explosion—a runaway exothermic decomposition that can be explosive. This distinction is crucial for safety: cooling and preventing heat buildup are essential, because confinement or contamination can trigger the runaway. The other descriptions imply rapid detonation/deflagration or no possibility of a thermal explosion, which doesn’t fit Type B behavior.