Which factor most directly contributes to a runaway reaction in a storage scenario?

• A. Adequate ventilation
• B. Proper labeling
• C. A localized high-temperature area (hot spot)
• D. Regular cleaning.

Answer: (C)

Runaway reactions in storage happen when the heat generated by an exothermic process isn’t removed quickly enough, so temperature climbs and the reaction rate speeds up in a self-accelerating loop. A localized high-temperature area, or hot spot, directly creates this situation: it concentrates heat in one spot, raising the local temperature and driving the reaction to release even more heat. That extra heat further accelerates the reaction, making the hot spot grow and the system harder to control.

Safety and management practices like ventilation help remove heat and vapors, reducing risk, but they don’t by themselves initiate a runaway. Proper labeling and regular cleaning are important for safe handling and reducing other hazards, but they don’t directly cause the self-accelerating heat buildup that a hot spot can trigger.