What does 'flow path' refer to in a burning building?

• A. The path of water from the hydrant to the nozzle during firefighting.
• B. The movement route for occupants and smoky air from high-pressure zones to low-pressure zones created by ventilation and openings.
• C. The sequence of alarms activated during the incident.
• D. The route of electrical power distribution during a fire.

Answer: (B)

Flow path is the route air, heat, and smoke take inside a burning building, driven by pressure differences created by ventilation and openings. When doors or windows are opened or damaged, higher pressure air pushes into the space while smoke and hot gases are drawn toward exhaust openings, so the flow path traces the path those gases follow between compartments. This concept helps explain where visibility will worsen, where heat and smoke will travel, and how ventilation actions will affect fire behavior and occupant safety. Other options describe water supply, alarm sequencing, or electrical power routing, which aren’t about how air and smoke move through a structure.