State University Extension
Home Maintenance And Repair - 01500213
Pretesting Carpet Cleaning Products
Pretest so cleaning problems will not develop during cleaning or after
the carpet or rug is cleaned.
Not all products can be safely used on all fibers and dyes. The face
yarns of a carpet can be dyed by many different dye processes using a
wide range of dyes. It is common in multi-colors to have different
types of dyes to produce the desired color. Therefore, a cleaner may be
safe on one color and not another.
To test a product, mix it according to directions or as it is planned
to be used. In an inconspicuous area, such as in a corner, behind a
chair, in back of the drapery, etc., place approximately one teaspoon
of the solution on a spot about the size of a nickel. Work the solution
in with the fingers, press a white tissue against the wet spot and hold
it there for about ten seconds. Examine the tissues to see if any dye
has transferred. The amount transferred may be very small and difficult
to see on the tissues, but over a large area of carpet it could be
objectionable. If the small spot tested does not include all the
different colors, then the others should be tested. Retest any color
that may be in doubt. The wet spots should be carefully examined as
they may show a change not apparent on the tissues.
This testing should show any damage or change that may take place on
the fibers. The chance of damage occurring with a cleaning solution is
very small, but some spot removal chemicals can damage some fibers. The
fibers may become sticky, soft, or dissolve. Always test and examine
carefully to prevent being sorry later.
If, during testing, a dye transfers or it appears as though a fiber is
being damaged, then this product should not be used. Try testing other
products until a safe one is found. If none can be safely used, then
contact and explain the problem to a professional.
A second test will determine the type of residue that remains after the
carpet or rug has been cleaned. The cleaning solution is made up of
various chemicals and liquids. After this is applied, the liquid will
start to evaporate. The drying time will vary from several hours to
After the liquid evaporates, what type of material remains on the
fibers? If it is a powdery, granular material, it will be removed with
the vacuum. Any other consistency will remain on the face fibers.
To determine the type of residue, pour one-half cup of the product as
it is to be used in a glass pie plate. Allow the pie plate to set
undisturbed until all the liquid has evaporated. This may take several
days. The process can be speeded up by placing the pie plate, with
solution, in an oven at 160 F. Watch and remove the plate when no more
liquid is being evaporated.
Examine the residue that remains. Is it sticky? If so, it will hold
onto soil at an accelerated rate and make the carpet soil faster. The
sticky residue will also hold the fibers together and the surface of
the carpet will be more matted and less resilient. A hard, waxy residue
will not hold onto soil to the same extent but it will dull the surface
and the fibers will not appear bright and clean.
Once the sticky or waxy residue gets on the fibers, it usually remains
until the residue is flushed out with a lot of warm water. Another
cleaning with the same solution will only build up the residue. If it
is suspected that a residue is already present on the carpet yarns,
place a tablespoon of warm water on a spot and work it in with the
fingers. A foam or a slippery feeling will indicate a detergent
residue. The best way to remove it is by the hot water extraction
method. Many professional rug cleaners have this type of equipment or
it can be rented.
This article was written by Anne Field, Extension Specialist, Emeritus,
with help from Margaret Boschetti, previous Extension specialist and
the Carpet and Rug Institute.
to main page
This information is for
educational purposes only. References to commercial products or trade
names does not imply endorsement by MSU Extension or bias against those
not mentioned. This information becomes public property upon
publication and may be printed verbatim with credit to MSU Extension.
Reprinting cannot be used to endorse or advertise a commercial product
MSU is an
employer. Michigan State University Extension programs and materials
are open to all without regard to race, color, national origin, gender,
gender identity, religion, age, height, weight, disability, political
beliefs, sexual orientation, marital status, family status or veteran
status. Issued in furtherance of MSU Extension work, acts of May 8 and
June 30, 1914, in cooperation with the U.S. Department of Agriculture.
Thomas G. Coon, Director, MSU Extension, East Lansing,MI 48824. This
information is for educational purposes only. Reference to commercial
products or trade names does not imply endorsement by MSU Extension or
bias against those not mentioned.
information.was reviewed as
of June 2008. For more information about the contents please
for webpage problems