Burning Characteristics of Fibers

The way a fabric burns depends partly on its fiber content. The Table below describes typical burning characteristics of fibers, ranking them from the most to least hazardous.
 

	Natural Cellulosic Fibers
	Cotton/Linen	Burn with a yellow flame, light smoke, and have glowing embers. Cellulosic fibers do not melt or draw away from flames.
	Manufactured Cellulosic Fibers can burn quickly when ignited, but they behave somewhat differently as they burn.
	Rayon/Lyocell	Burn similarly to cotton and linen, except they may shrink up and become tighter.
	Acetate	Burns with a rapid flame and melts when burning. May melt and pull away from small flames without igniting. Melted area may drip off clothing carrying flames with it. When flames have died out, the hot, molten plastic residue is difficult to remove.
	Synthetics may catch fire quickly or shrink from the flame initially, but ultimately, they will sputter, flame, and melt to the skin or the flaming melt will drop to the floor.
	Acrylic	Burns similarly to acetate, except that it burns with a very heavy dense black smoke. It drips excessively.
	Nylon, Polyester, Spandex, Lastol, and Olefin,	Burn slowly and melt when burning. May melt and pull away from small flames without igniting. Melted area may drip off clothing carrying flames with it but not to the extent of acetate and acrylic.
	Protein fibers are difficult to ignite. They may self-extinguish, but this varies depending on the closeness of the weave or knit (fabric density) and other finish treatments.
	Wool and Silk	Burn slowly and are difficult to ignite. May self extinguish
	Flame Resistant Fabrics are difficult to ignite, burn slowly and go out when the source of the flame is removed.
	Modacrylic and Saran	Burn very slowly with melting. May melt and pull away from small flames without igniting. Self extinguishes.
	Aramid, novoloid, and vinyon	Char but do not burn

Fabrics that are a blend of two or more fibers do not burn in the same way as either fiber. Sometimes, blends are more dangerous than either fiber. For example, fabrics of 50 percent cotton and 50 percent polyester tend to burn longer than a similar fabric of either cotton or polyester.

The way a fabric is made (knit, weave, lace, etc.) affects how it burns.

• Heavy close structures ignite with difficulty and burn more slowly than light, thin, or open fabrics.
• In general, summer weight clothing is more likely to catch fire than winter weight fabrics. However, heavy weight fabrics burn longer when ignited, because there is more flammable material present.
• Fabrics with more of the fiber surface area exposed to air have more oxygen available to support burning and therefore burn more easily. Thus, thin, gauzy fabrics, lace, or brushed fabrics can be very flammable.
• Fabrics with a napped or brushed surface of fine fibers can catch fire easily because of the greater amount of fiber surface exposed to oxygen in the air.

Adapted from Facts About Fabric Flammability, North Central Region Extension Publication 174, Revised July 2003. www.extension.iastate.edu/pubs/cl.htm