Which foam application method is best for an open-top storage tank fire?

The bounce-off method is particularly effective for open-top storage tank fires primarily due to its ability to create a barrier of foam over the burning surface. This technique involves applying foam at an angle to allow it to bounce off the surface of the burning liquid, thereby creating a blanket of foam that suppresses the flames and inhibits the release of flammable vapors.

This method provides adequate coverage while minimizing the risk of disrupting the burning surface, which can occur with other techniques. It also helps to contain the fire and prevent it from spreading, making it a suitable option for controlling fires in tanks that are open to the atmosphere. The foam can effectively smother the fire by cutting off the oxygen supply and cooling the heat, which is crucial for extinguishing the fire efficiently.

While other methods like roll-in, rain-down, and subsurface injection may have their uses in different contexts or types of fires, they do not offer the same balance of coverage, vapor suppression, and minimal disturbance that is critical for dealing with an open-top storage tank fire.