Flannel Flame Retardance?

[Sage_Rat]

I heard, growing up in a town of lumberjacks, that flannel was supposedly flame retardant. The fuzziness would burn off quickly, leaving the body of the shirt untouched so it acted to block and protect the wearer for brief contact with flames.

Truth?

[Waenara]

@Sage_Rat

I heard, growing up in a town of lumberjacks, that flannel was supposedly flame retardant. The fuzziness would burn off quickly, leaving the body of the shirt untouched so it acted to block and protect the wearer for brief contact with flames.

Truth?

It probably depends if the flannel is made from 100% wool. Wikipedia sez flannel was originally made from wool, but now wool/cotton or wool/synthetic blends are made. There is also cotton flannelette.

Wool is naturally fire-retardant. It resists catching fire, and if you start to burn a tuft of wool or woolen fabric is will self-extinguish. I knit and I am learning to spin my own yarn, and one test to determine what type of fiber you have is a “burn test”. You try to light the yarn with a match or lighter and if it self-extinguishes then it’s at least partly made from animal-based fiber (sheep, llama, alpaca, etc…)

Wool Characteristics:

Wool ignites at a higher temperature than cotton fibers and some synthetics. It has lower rate of flame spread, low heat release, low heat of combustion, and doesn’t melt or drip; it forms a char which is insulating and self-extinguishing, and contributes less to toxic gases and smoke than other flooring products, when used in carpets. Wool carpets are specified for high safety environments, such as trains and aircraft. Wool is usually specified for garments for fire-fighters, soldiers, and others in occupations where they are exposed to the likelihood of fire.

[Waenara]

I found this great chart with the characteristics of different fibers when they burn.