Carpet Fiber Identification for Carpet Cleaners

Now, don’t get concerned that you must identify the fibers before starting to clean! 99% of the time, cleaning carpet is just coming in to the home (or business), leaving your literature with the customer, doing a pre-inspection (preferably with the customer), cleaning, sometimes doing some spotting and applying carpet protector (if you were able to sell this extra service). The only time we need to know the fiber type is when we see problems or when we must get very aggressive in cleaning or spotting. For example, if it’s 100% olefin, we can use chlorine bleach for spotting, BUT, we cannot use a hot iron and we should not apply a carpet protector to olefin. With wool, we are very restricted in what chemicals we can use for cleaning and spotting. Fortunately both fibers are easy to test for.

Olefin carpet fiber is easily tested for – it is the only fiber that floats in water! To test, simply place some fiber in a glass of water, or preferably some very diluted detergent, hold it under the surface of the water, and squeeze out all the trapped air, and let go. If the fiber floats, it’s olefin! BUT, if you’re planning on using chlorine bleach, test with chlorine bleach too in case this is a nylon-olefin blend.

Wool fiber type is also easy to test for. First, if the carpet or rug smells like a wet dog when you’re cleaning it – it’s wool! In addition, you can always run a “burn test”. Use a butane lighter to melt or ignite an unknown fiber to determine its type (never use a match). The purpose of using butane lighter is to avoid masking the odor of the burning fiber. Burned wool smells like burned hair. Burned silk smells like burned feathers. Additionally, wool dissolves in undiluted chlorine bleach.

Chemical fiber tests are more difficult requiring the use of such things as formic acid and hot cresylic acid. The good thing with carpet fiber is that if it’s not wool and it’s not olefin, both of which are easy to test for, it most likely is nylon!

Burn Tests to Determine Carpet or Rug Fiber Type:

Use a butane lighter to melt or ignite an unknown fiber to determine its type. Never use a match. The purpose of using a butane lighter is to avoid masking the odor of the burning fiber since the butane flame is odorless.

• Acrylic:
  Melts and shrinks from an approaching flame and ignites quickly. In the flame, burns rapidly with bright, sputtering flame with a lot of smoke. When withdrawn from the flame, it continues to burn, melts, and drips. It has an acrid odor and results in a hard, irregular black bead.
• Cellulose:
  Cellulosic fibers, such as cotton, burns and the ash crumbles – as do protein fibers such as wool and silk.
• Corterra:
  Similar to polyester.
• Cotton/Linen:
  Cellulosic fibers such as cotton and linen ignite readily with an approaching flame and scorches. Once in the flame, it burns rapidly with yellow flame. When pulled out of the flame, it continues to burn rapidly with a red afterglow upon extinguishing. Smells like burning paper. Its burned residue is a gray to charcoal colored light feathery ash, which easily crumbles.
• Nylon:
  Melts and shrinks from an approaching flame. In the flame, melts and burns slowly and is smoky. Once out of the flame, burns slowly and tends to self-extinguish. Burning nylon smells like celery. Its burned residue is a hard, shiny brown or gray bead.
• Polyester:
  Melts and shrinks from an approaching flame. In the flame, melts and burns slowly. When withdrawn from the flame, it burns slowly, melts and drips. Has a slightly sweet smell. It produces a hard, shiny black or brown bead.
• Polypropylene (Olefin):
  Melts and shrinks from an approaching flame. In the flame, it melts and burns. When withdrawn from the flame, it continues to burn. It has a candle wax odor and produces a tough, tan bead.
• Protein:
  Protein fibers, such as wool, burns and the ash crumbles – as do cellulosic fibers such as cotton.
• Rayon:
  Scorches and ignites readily with an approaching flame. In the flame, burns rapidly with a blue flame. When withdrawn from the flame, continues to burn rapidly with a red afterglow when the flame is extinguished. Smells like burning paper, leaves a gray to charcoal color light feathery ash.
• Silk:
  Curls away from an approaching flame. In the flame, it burns slowly and sputters. Weighted silk glows red. Out of the flame, it is self-extinguishing or may burn very slowly and smells like singed hair. Its residue is round, shiny black beads, easily crushed. Weighted silk has the skeleton of the original fiber.
• Wool:
  Chars and curls away from an approaching flame. In the flame, it burns slowly and unevenly. Once pulled out of the flame it is self-extinguishing. It smells like burning hair. It has a brittle, irregular black ash. As with cotton and linen, protein fibers’ ashes readily crumble.