By observing how fabric burns, what kind of smell it gives off, and the residue it leaves behind, you can tell what type of fiber a fabric is made out of.

Fabric Burn Test Chart

Natural Plant Fibers

Cotton – Key Characteristics When Burned:

• Steady burn with clear flame and afterglow
• Smells like burning paper or wood
• Leaves very little ash

Linen – Key Characteristics When Burned:

• Steady burn (but less rapid than cotton)
• Smells like burning paper or wood
• Leaves ash

Natural Animal Fibers

Silk – Key Characteristics When Burned:

• Burns slowly and self extinguishes
• Smells like burning hair
• Brittle residue that can be crushed

Wool – Key Characteristics When Burned:

• Burns slowly and self extinguishes
• Smells like burning hair
• Brittle beads that can be crushed

Manmade Fibers

Tencel – Key Characteristics When Burned:

• Steady burn with yellow flame
• Smells like burning wood
• Leaves gray ash

Synthetic Fibers

Acetate – Key Characteristics When Burned:

• Burns rapidly while melting
• May smell like vinegar
• Hard, dark bead that can’t be crushed

Acrylic – Key Characteristics When Burned:

• Burns rapidly while melting
• May smell like chemical
• Hard, black bead that can’t be crushed

Polyester – Key Characteristics When Burned:

• Stops burning and shrinks from flame
• May smell like sweet chemical
• Hard, dark bead that can’t be crushed

Nylon – Key Characteristics When Burned:

• Stops burning and shrinks from flame
• May smell like plastic or celery
• Hard, black bead that can’t be crushed

True Story: I’ve requested 100% cotton fabric before, and despite the fabric supplier reassuring me that it was pure cotton, the fabric burn test said otherwise. Be extra careful, and always do a burn test if you’re suspicious about the composition (or the supplier! Yikes!).

Step-by-Step Guide to Conducting a Fabric Burn Test

1. Prepare Your Tools

• Small piece of fabric (1” x 1” scrap is enough)
• Stainless steel tweezers
• Candle or lighter
• Non-flammable surface (an old ceramic plate or metal tray)
• Water (in case you need to put out the fire!)

2. Conduct the Burn Test

Holding your fabric sample with tweezers, light one corner on fire using a match or lighter. Let the fabric piece burn completely, and drop the fabric on your tray if necessary.

3. Take Note of the Results

• Watch how it burns: Synthetics tend to melt and continue burning despite being pulled away from the flame source, while naturals tend to burn like paper and self-extinguish.
• Smell the smoke: Wafting it toward your face (DO NOT SMELL DIRECTLY). Cotton smells like burning paper, wool and silk may smell like burning hair, synthetic fibers often have a chemical smell.
• Examine the ash: Natural fibers tend to leave soft ash while synthetic materials often leave hard plastic-like beads.

Fabric Burn Test Guide