Which equipment is designed to smother flames in a Class B fire?

The correct answer is a dry chemical extinguisher, as it is specifically designed to combat Class B fires, which involve flammable liquids such as gasoline, oil, and paint. These extinguishers contain agents like monoammonium phosphate, which act by creating a barrier between the fuel and the oxygen in the air, effectively smothering the flames. This is crucial because traditional methods, like water from a hose, could worsen a Class B fire by spreading the flammable liquid instead of extinguishing it.

Using a fire blanket can be effective in some scenarios, like containing small fires or extinguishing flames on a person, but it is not specifically designed for Class B fires. Similarly, a sprinkler system is typically used for a broader range of fire types and may not effectively tackle the unique challenges presented by flammable liquids. Therefore, the dry chemical extinguisher is the most suitable choice for effectively smothering flames in a Class B fire situation.