Fire in a Box · Lesson 02
Flow Path
Openings change the flow path, so before you open a door or break a window, do you know what to expect?
A door, a window, a stairwell, a change in wind: each offers a way to affect the movement of air, heat, and smoke through a building.
This class connects pressure and gas movement with compartment geometry, openings, and construction. Case discussions encourage crews to explain their expectations. Learn the science behind what is happening and understand how to control the flow path as fire conditions within the box change.
Inside the conversation
- Pressure differences and movement through openings.
- Neutral plane, wind, laminar and turbulent flow, and stack effect.
- Door control and flow paths through different building types.
Bring it to the kitchen table
Have you ever questioned the textbook definition of ventilation: removing heat and products of combustion and replacing them with cooler air? If that's true, why does the fire get hotter when I ventilate?
In a potential rescue situation, should I vent the structure to increase its survivability and tenability? If “vent for life” is right, why do the NIST studies say ventilation increases the heat release rate of an underventilated fire?