How to Identify Textile Fibers Using the Burn Test

Published December 23, 2025 Last updated April 27, 2026 1 min read

If you want a quick and reliable way to identify different textile fibers, the burn test is one of the most effective methods. By observing how a fiber reacts to flame, you can determine whether it is natural or synthetic and even pinpoint the exact type of fiber.

Why Use the Burn Test

The burn test is useful because each fiber reacts differently to heat:

Flame behavior – How fast it burns, whether it melts, curls, or shrinks.

Smell – Burning fibers release distinctive odors.

Residue – The ash left behind varies in texture, color, and fragility.

How to Perform the Burn Test Safely

Cut a small fiber sample – A few strands are enough.

Use tweezers – Hold the fiber safely away from your hand.

Light a flame – A candle or lighter works.

Observe closely – Watch how the fiber burns, the smell, and the ash left behind.

Extinguish safely – Have water or a fireproof surface nearby.

⚠️ Safety tip: Always perform the burn test in a ventilated area and keep a small amount of fiber for comparison.

Fiber	Burns or melts	Type of flame	Rate of burning / melting	Smoke color	Smell	Residue
NATURAL: CELLULOSE
Cotton	burns	yellow	fast	grey	burnt paper	fine, soft, grey ash
Linen	burns	yellow	fast	grey	burnt paper	smouldering soft grey ash
NATURAL: PROTEIN
Wool	burns	irregular, slight hiss	slow	blue/grey	burnt hair or feathers	crisp, black bead, crushes easily
Silk	burns	irregular, slight hiss	slow	grey	burnt hair or feathers	crisp, black bead, crushes easily
MAN-MADE: REGENERATED FIBRES
Viscose rayon	burns	yellow	fast	grey	burnt paper	fine, soft, grey ash
Cellulose acetate	melts	yellow	fairly slow	grey	burnt paper, vinegar	scorched bead, crushes
Cellulose triacetate	melts	yellow	fairly slow	grey	burnt paper, vinegar	scorched bead, crushes
MAN-MADE: SYNTHETICS
Nylon	melts	yellow	quite fast	grey	celery	very hard, light brown bead
Polyester	melts	yellow	quite fast	grey	quite sweet	very hard, black bead
Acrylic	melts	luminous	very fast	black	acrid	hard, black irregular bead

Frequently asked questions

What is a burn test and is it accurate?

The burn test is a low-tech method for identifying fibres by observing how they react to flame — the smell, the way the fibre burns, and the residue left behind. It is highly reliable for distinguishing natural fibres (cotton, silk, wool, linen) from synthetics (polyester, nylon, acrylic), though it cannot tell apart very similar fibres within the same family.

Is the burn test safe to perform at home?

Yes, with basic precautions. Always work in a well-ventilated area, keep water or a fireproof surface within reach, use long tweezers to hold the sample away from your hand, and never burn large pieces of fabric. A small thread or 1-inch swatch is plenty.

How can I tell silk from polyester using the burn test?

Silk burns slowly with the smell of burnt hair and leaves a brittle, crushable black ash. Polyester melts before it burns, smells faintly chemical or sweet, and leaves a hard plastic-like bead that you cannot crush between your fingers.

Will the burn test work on blended fabrics?

Partially. A blend will show characteristics of both fibres — for example, a cotton/polyester blend will char like cotton but also produce a melted bead like polyester. For accurate identification of blends, lab testing is more reliable.

Do I need special equipment?

No. You only need a candle or lighter, a pair of tweezers, a non-flammable surface (like a ceramic plate), and a small fibre sample taken from a hidden seam allowance of the fabric.

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How to Identify Textile Fibers Using the Burn Test

Why Use the Burn Test

How to Perform the Burn Test Safely

Frequently asked questions

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