Premature ventilation without interior coordination can accelerate which fire behavior event?

• A. Overcooling.
• B. Thermal runaway.
• C. Flashover.
• D. Smoke stratification.

Answer: (C)

Ventilation is a tool that must be coordinated with interior fire attack to control how fast a fire grows. When ventilation is done prematurely and without interior coordination, fresh air is drawn into a hot, fuel-rich environment and the heat release rate spikes. That boost in oxygen and airflow accelerates the combustion of exposed fuels, driving the compartment toward a rapid transition known as flashover, where the room becomes fully involved as contents ignite almost simultaneously.

In other words, uncoordinated venting feeds the fire too quickly and too aggressively, making the moment when everything in the space ignites occur sooner. The other options don’t fit as directly: cooling effects or smoke layering aren’t the primary accelerated outcomes of uncoordinated venting, and while thermal runaway can occur, the specific fire behavior most associated with uncontrolled ventilation is the sudden, rapid spread culminating in flashover.