What is the best term for the movement of heat and smoke from high pressure to low pressure?

What is the best term for the movement of heat and smoke from high pressure to low pressure?

• A. Flow Path
• B. Ventilation path
• C. Heat channel
• D. Pressure gradient

Answer: (A)

During a fire, heat and smoke move from areas of higher pressure to lower pressure along the actual route they follow through openings in the building. That route is what we call the flow path: the path heat and smoke take as it travels from the origin compartment toward exhaust openings like doors, windows, or stairwells. The pressure difference is the driving force, but the term flow path emphasizes the real channel these products travel through, not just the cause.

Using the other terms isn’t as accurate here. Pressure gradient describes the driving force itself—the difference in pressure—rather than the movement’s route. Ventilation path and heat channel aren’t standard terms used to describe this behavior in fire science. So the best fit for describing how heat and smoke move from high to low pressure is flow path.