Wicking is the process by which what occurs?

• A. Fuel Absorbed Into A Material
• B. Fuel Evaporated From A Surface
• C. Fuel Mixes With Air
• D. Fuel Cools A Surface

Answer: (A)

Wicking is about a liquid being drawn into and held by a porous material through capillary action. When fuel contacts a fabric or other absorbent material, adhesive forces between the fuel and the material pull the liquid into the pores, saturating the material and spreading the fuel beyond the original spot. This is why fuel-soaked rags or wicks can carry fuel away from the spill area and potentially spread a fire—that movement into the material is the essence of wicking.

This differs from evaporation, where the liquid turns into vapor and leaves the surface, or from mixing with air, which describes the vapor getting into the air rather than being absorbed by the material. It also isn’t about cooling a surface, which would involve heat transfer rather than liquid movement into a solid.