Which sign indicates a ventilation-controlled fire with exterior doors and windows warming to the touch?

• A. Exterior doors and windows warm to touch
• B. Windows are clearly visible and open
• C. Smoke colors are white
• D. All interiors remain cold

Answer: (A)

In a ventilation-controlled fire, the amount of heat released is driven by the oxygen available through openings. If exterior doors and windows are warming to the touch, it shows that a lot of heat is reaching those surfaces from inside the building. This warming indicates high heat release at the boundary of the structure and that ventilation is influencing the fire’s growth — a hallmark of a ventilation-controlled scenario.

Other signs are less reliable indicators. Windows being clearly visible and open simply shows there is ventilation, but it doesn’t prove the fire is ventilation-controlled. Smoke color being white isn’t a definitive cue for ventilation control, since smoke color can vary with fuel and conditions. All interiors remaining cold would contradict the presence of intense heat reaching exterior surfaces and doesn’t fit a heat-driven, ventilation-limited state.