Which statement best describes a ventilation-controlled fire?

Which statement best describes a ventilation-controlled fire?

• A. Growth is limited by fuel supply.
• B. Growth is limited by heat release rate.
• C. Growth is limited by water supply.
• D. Growth is limited by oxygen supply.

Answer: (D)

In a ventilation-controlled fire, the speed at which the fire can grow is governed by how much oxygen can be brought into the space. When ventilation is limited, oxygen is the limiting factor, so the heat release rate and overall growth are constrained even if there’s plenty of fuel. If ventilation increases, more oxygen becomes available and the fire can grow rapidly. That’s why the best description is that growth is limited by the oxygen supply, not by fuel, water, or other factors.