“Jessika, in a recent article you mentioned performing a carpet fiber identification test. Can you please explain this a little more?”
Ryan, Sunshine Cleaning, N.C.
Carpet fiber identification is a vital step in the cleaning process. Proper identification will tell the professional cleaning technician exactly which carpet fiber he or she will be working with, and which methods, procedures and cleaning solutions will be safe to use. Identification will also reveal specific soiling characteristics and stain removal probability so that the cleaning project can be accurately pre-qualified and any potential issues or over expectations can be addressed and discussed with your client before cleaning services are started.
There are two main objectives when performing carpet fiber identification tests:
Is the fiber synthetic or natural? Or a possible blend?
If the fiber is synthetic, is it nylon, olefin or polyester?
As mentioned above, project pre-qualification and communication with your client is key to avoiding any complaints over expectations. Here is a short list of fiber characteristics that can help with the pre-qualification process.
Natural fiber such as wool, silk, cotton and jute will require the use of specialty cleaning solutions formulated for cleaning these delicate fibers. As these natural fibers are very absorbent, technicians must maintain control of moisture by monitoring the amount of cleaning solutions used and, if possible, turn the cleaning tool injection pressure down to avoid over-wetting.
Nylon, a synthetic fiber, has the ability to absorb dyes from urine, food and beverage spills that can lead to permanent staining issues if not addressed in a reasonable amount of time. Oil and grease spots should be readily released from the carpet with normal cleaning procedures. Pre-spotting or adding a citrus solvent booster to your pre-spray can help remove most, if not all, of the tenacious oil or grease spots.
Olefin and polyester carpet fiber are oleophilic – they have the ability to hold onto grease and oil stains that may cause a permanent yellow or tan discoloration and the use of a gelled citrus solvent pre-spotter along with a citrus booster added to your pre-spray is highly recommended. These synthetic fibers are not as absorbent as nylon (olefin is the least absorbent fiber with polyester as a close runner-up!) and urine stains or acid dye stains should be fairly easy to remove, depending on the time that they have been in the carpet.
The Burn Test
Performing a burn test is a simple and relatively accurate way to identify the fiber content of the carpet you will be working on. Performing a burn test takes a bit of practice but is simple, effective and can be done on-site. You will need tweezers, an ashtray and a butane lighter (matches have a sulfur odor that can interfere with the test where butane lighters are odorless). When using this method, the technician evaluates several things:
The color and action of the flame
The color of the smoke
The odor of the burning fiber
The color and luster of the burned fiber
The shape and hardness of the burned fiber
Synthetic fibers will burn and melt, usually resulting in a hard plastic bead with the exception of acrylic, as it will crumble. Natural fibers will have an easily-crumbled, sometimes powdery ash. Since wool and silk are naturally flame-resistant, they do not burn or sustain the flame easily, but beware of a natural and synthetic fiber blend. Always remove a tuft of carpeting from an inconspicuous area and perform the burn over a safe, non-flammable surface.
How to Perform a Burn Test:
Remove a tuft of carpeting from an inconspicuous area.
Hold tuft by the end with tweezers over an ashtray or safe surface.
Slowly bring the flame of butane lighter to the tip of the carpet yarn.
Once yarn is burning, evaluate flame color, flame motion and smoke.
Blow out flame and evaluate odor.
When burnt yarn is cool, evaluate the bead or ash.
Compare findings to the Burn Test Chart to determine fiber content.
Be wary of fiber blends, especially with wool carpeting.
The Chemical Test
The most common field chemical test done today is with formic acid, a product that can be purchased at most professional carpet cleaning supply stores and sometimes called “Fiber ID Acid.” Formic acid will dissolve nylon fibers, yet will not dissolve olefin or polyester fibers. Another available chemical test is a strong chlorine bleach solution. This solution will soften or dissolve wool and silk fibers.
The Float Test
Lastly, there is another test for fibers called the “Float Test.” When fibers are submerged in water, olefin is the only synthetic fiber that will float due to its specific gravity that is less than water.
For further information of fiber characteristics, field testing and cleaning processes, I would recommend that you contact the IICRC at www.iicrc.org
for higher education and certification classes in carpet cleaning.