Although no fabric is fireproof, certain textiles resist fire better than other fabrics. Fire-resistant fabric, also known as flame-retardant fabric, is so designated based on the time it takes for the fabric to burn. Fire-resistant fabric may be naturally fire resistant because of its natural fiber weave, or treated with a fire-resistant chemical to resist heat and flames.

Wool

Wool is generally considered the most flame-resistant natural fiber,  because it is difficult to ignite, and flames are often extinguished in the fibers.  Natural fibers, such as silk, cotton and wool, are more susceptible to fire than manufactured fibers, but cloth manufacturing techniques can improve their fire resistance.  Natural fibers can be treated with a chemical solution that improves flame resistance.  When a material made of natural fibers is constructed with a tight weave,  the material provides improved flame resistance.