Final answer:
The best results in extinguishing a flammable liquid fire in a large tank are obtained by directing a foam solution at the base of the fire, which creates a barrier between the liquid fuel and air, suffocating the fire.
Step-by-step explanation:
When addressing a flammable liquid fire with a depth of more than 6mm, such as one in a large tank, the most effective method of fire extinguishing involves the application of a fluorinated foam solution. This foam can spread across the burning liquid surface, creating a barrier between the fuel and the air that extinguishes the fire. The optimal point of application for this foam is at the base of the fire, where it can effectively cut off the fire's fuel source.
In terms of handling flammable chemicals, it is vital to follow safety instructions meticulously, including not exposing chemicals to heat sources unless directed by an expert. The application of these safety measures and the utilization of fire extinguishers, especially those containing liquid CO₂ on cooler days when it's present in the extinguisher, is crucial when dealing with fires of this nature.