How does wind speed influence the hazard of a surface pool fire near ground level?

• A. It has no effect on flame shape or heat exposure.
• B. It stretches and tilts the flame, influences evaporation rate, and affects downwind radiative heat exposure and ground-level cooling or heating.
• C. It only changes the color of the flame without altering hazard.
• D. It reduces evaporation rate and extinguishes the flame.

Answer: (B)

Wind speed reshapes how a surface pool fire behaves by moving heat and vapors through the air. When wind blows, the flame is stretched and tilted in the wind direction. That tilt changes where and how much radiant heat reaches objects at ground level downwind, so the heat exposure isn’t just from the flame upright—it shifts and often increases for targets downwind. At the same time, the moving air enhances heat transfer to the pool surface, raising the evaporation rate. More evaporation means more fuel vapors in the plume, which can spread hazard further and alter ignition potential downwind. The wind also influences how the ground near the fire is heated or cooled: strong winds can carry heat away and cool surfaces, or, if the flame tilts toward the ground, can deliver more radiant and convective heat to the ground itself. All of this means wind speed markedly changes both how the flame looks and how hot things get downwind and at ground level, making the hazard dependent on the interplay of flame geometry, evaporation, and heat transfer.