Small Scale Fire Behavior Prop Demonstration

Summary

This video demonstrates small-scale fire behavior training using a specialized box prop. Led by Sean Gray and Deputy Chief PJ Norwood, the session covers how to set up, burn, and teach firefighters the fundamentals of fire behavior. The box simulates different fire scenarios, highlighting how ventilation, oxygen control, and modern vs. legacy fuels affect fire dynamics. The training emphasizes the importance of understanding smoke color, velocity, and neutral planes. Techniques such as ventilation-induced flashovers and bi-directional flow are showcased, teaching valuable lessons in fire tactics and firefighter safety.

Takeaways

• 🔥 The fire behavior training uses a box to simulate real fire scenarios, allowing firefighters to understand and control fire behavior.
• 🌾 Fuel is placed only in the lower left compartment, consisting of dry straw and pine strips, with no additional fuel in the other compartments.
• 💨 Observing smoke characteristics, such as color, velocity, and density, is crucial for understanding fire behavior.
• 🚪 Ventilation control is key in manipulating fire growth, by opening or closing compartments to increase or decrease oxygen flow.
• 🧪 Polystyrene materials (e.g., styrofoam cups) are added to simulate modern fuel, showing the difference in smoke density and color.
• 🌫️ The demonstration emphasizes the importance of bi-directional flow and neutral planes in fire behavior, especially in structural fires.
• 🔥 Ventilation can drastically change fire behavior, sometimes leading to flashover if not carefully managed with proper openings.
• 🪵 Controlling airflow can effectively choke out a fire, similar to shutting an oven door during a fire to smother it.
• 🏠 The training simulates various fire scenarios, including vertical ventilation and roof operations, to demonstrate the effects of adding or removing oxygen.
• 💡 The drill highlights that ventilation does not cool a fire, only water does, and ventilation must be coordinated with firefighting operations.

Q & A

What is the main focus of the training discussed in the script?

The main focus of the training is small-scale fire behavior and how to teach firefighters about it using a fire behavior training prop.

What materials are initially used to start the fire in the training box?

The materials used to start the fire are dry straw and pine strips, which are placed only in the lower left compartment of the training box.

Why is only the lower left compartment filled with fuel?

The fire behavior is intended to begin in the lower left compartment, and as the fire progresses, the box itself becomes the fuel, hence no additional fuel is needed in the other compartments.

How does controlling ventilation openings affect the fire behavior?

Controlling ventilation openings by opening and closing them can change the fire behavior by either decreasing or increasing the amount of oxygen into each compartment.

What is the purpose of adding polystyrene materials to the fire?

Polystyrene materials are added to demonstrate the difference in smoke characteristics, such as density and color, when modern fuel packages are involved.

What does the color and density of the smoke indicate during the training?

The color and density of the smoke indicate the type of fuel burning. Light-colored smoke signifies legacy fuels like hay or straw, while darker and denser smoke indicates the presence of modern fuels.

What is a neutral plane and how is it demonstrated in the training?

A neutral plane is the level where the smoke and hot gases separate from the cooler, fresh air. It is demonstrated when the smoke escapes out the top of the box and fresh air is drawn in from the lower part.

How does the fire behavior change when the lower right compartment's door is opened?

Opening the door between the lower left and lower right compartments changes the fire behavior by allowing the lower left to become an outlet, and the lower right to experience bi-directional flow with an exhaust and intake of fresh air.

What is the significance of the fire flashing when the lower left compartment is opened?

The fire flashing when the lower left compartment is opened signifies that the fire is rapidly transitioning to a more aggressive state due to the increased availability of oxygen.

How does roof ventilation affect the fire behavior as demonstrated in the training?

Roof ventilation, when properly coordinated with fire attack, can be positive by increasing the velocity and density of the smoke, but it requires breaking down the sheetrock to be effective, as demonstrated by opening the slide trays.

What is the key takeaway from the training regarding ventilation and fire behavior?

The key takeaway is that ventilation, whether through opening compartments or roof operations, significantly affects fire behavior by controlling the amount of air available to the fire, which in turn affects the heat and potential for flashover.