Which term describes the second stage where the fire begins to spread across the ceiling of the fire compartment?

Which term describes the second stage where the fire begins to spread across the ceiling of the fire compartment?

• A. Incipient stage.
• B. Decay phase.
• C. Fully developed stage.
• D. Growth phase.

Answer: (D)

Fire behavior in a compartment progresses through stages, with growth being the phase where the fire not only enlarges but starts to spread across surfaces, including the ceiling. In this stage the heat release rises and the hot gas layer near the ceiling expands, allowing flames to move along the ceiling and to other fuels. This is distinct from the incipient stage, which is just the initial ignition with limited spread; the fully developed stage is when the fire has engulfed much of the room and all fuels are burning; and the decay stage occurs as fuels are consumed and the fire wanes. So the description of the fire beginning to spread across the ceiling corresponds to the growth phase.