Fire blankets are safety devices designed to extinguish small fires or wrap around a person whose clothing has caught fire. Fire blankets are typically made of flame-resistant materials such as fiberglass, wool, or Kevlar and are treated with fire-retardant chemicals. Fire blankets are designed to smother the flames by cutting off the supply of oxygen, which is necessary for combustion. When used properly, fire blankets can quickly extinguish small fires, and prevent them from spreading.