What are the three methods of applying a foam stream?

The correct choice identifies the recognized methods of applying a foam stream, which are critical in firefighting operations involving flammable liquids. "Bank down," "Rain down," and "Roll on" indicate specific techniques that ensure effective foam application to control and extinguish fires.

• "Bank down" involves applying foam to create a barrier along the surface of the burning liquid. This technique helps to suppress the vapor that can be released from the fuel, minimizing the risk of re-ignition.

• "Rain down" means delivering foam from above to cover the burning surface. This method allows for a greater distribution of foam over the fire, ensuring a wide coverage area while also cooling the surrounding environment.

• "Roll on" refers to using the foam in a way that it rolls over the surface of the liquid, thus enveloping and extinguishing the fire efficiently. This action is particularly useful for controlling larger areas on fire.

These methods are specifically tailored to enhance fire suppression effectiveness by utilizing the physical properties of foam, which includes creating a barrier to smother flames and cool the fuel. Understanding these techniques is essential for firefighters to successfully manage and extinguish flammable liquid fires.