How do flame-resistant fabrics work ?

Flame-resistant (FR) fabrics and garments are intended to resist ignition, prevent the spread of flames away from the immediate area of high heat impingement, and to self-extinguish almost immediately upon removal of the ignition source.

 Normal work apparel will ignite and continue to burn if exposed to an ignition source such as flame or electric arc. Everyday fabrics will continue to burn until they are extinguished or all flammable material is consumed.