What is a Burn Test? How do I test a fabric?
Burn Test - CAUTION. WARNING. BE CAREFUL! This should only be done by skilled burners! Make sure there is a bucket of water nearby and that you burn in a metal bucket or non-plastic sink.
To identify fabric that is unknown, a simple burn test can be done to determine if the fabric is a natural fiber, man made fiber, or a blend of natural and man made fibers. The burn test is used by many fabric stores and designers and takes practice to determine the exact fiber content. However, an inexperienced person can still determine the difference between many fibers to "narrow" the choices down to natural or man made fibers. This elimination process will give information necessary to decide the care of the fabric.
WARNING: All fibers will burn! Asbestos treated fibers are, for the most part fire proof. The burning test should be done with caution. Use a small piece of fabric only. Hold the fabric with tweezers, not your fingers. Burn over a metal dish with soda in the bottom or even water in the bottom of the dish. Some fabrics will ignite and melt. The result is burning drips which can adhere to fabric or skin and cause a serious burn.
Cotton is a plant fiber. When ignited it burns with a steady flame and smells like burning leaves. The ash left is easily crumbled. Small samples of burning cotton can be blown out as you would a candle.
Linen is also a plant fiber but different from cotton in that the individual plant fibers which make up the yarn are long where cotton fibers are short.
Linen takes longer to ignite. The fabric closest to the ash is very brittle. Linen is easily extinguished by blowing on it as you would a candle.
Silk is a protein fiber and usually burns readily, not necessarily with a steady flame, and smells like burning hair. The ash is easily crumbled. Silk samples are not as easily extinguished as cotton or linen.
Wool is also a protein fiber but is harder to ignite than silk as the individual "hair" fibers are shorter than silk and the weave of the fabrics is generally looser than with silk. The flame is steady but more difficult to keep burning. The smell of burning wool is like burning hair.