What does a fire blanket do?

A fire blanket is designed primarily to smother small fires, particularly those that may occur in kitchens or on a person's clothing. When placed over a fire, the blanket cuts off the oxygen supply, which is essential for combustion, effectively extinguishing the flames. Additionally, fire blankets are made from materials that can withstand high temperatures, allowing individuals to use them to protect themselves from burns while attempting to control a fire or to wrap around a person whose clothing has caught fire.

The function of a fire blanket is not to extinguish large fires, as this typically requires specialized fire extinguishing equipment. It also does not provide shelter or serve as a first aid covering for injuries, which are roles filled by other types of emergency equipment. Thus, the primary purpose of a fire blanket makes the third option the correct choice in this context.