Nylon Degradation from Ultraviolet Light
This is not your typical shedding problem. The home builder was the commissioner and the carpet past the test for ultraviolet degradation.
PROBLEM REPORTED: Yarn Turned To Powder
PROBLEM FOUND: Ultra-Violet Light Degradation
WAS A DIAGRAM MADE?: No
SAMPLES FROM INSPECTION: None Taken
PERSONS PRESENT: Inspector & Claimant
THE CARPET
MANUFACTURER: Not Available
NUMBER on BACKING: Not Applicable
FIBER/ ID METHOD: Nylon/Chemical
FIBER HUE: Off White
CONSTRUCTION: Tufted Cut Pile
YARN STYLE: Saxony
SQUARE YARDAGE: Not Given
BACK SYSTEM: Conventional Tufted
PRIMARY BACKING: Polypropylene
SECONDARY BACKING: Action Back
LOCATION TYPE: Residential
DATE INSTALLED: 1/96
METHOD: Stretch-In
CUSHION: 1/2 Inch Rebond 6 Lb./Cu. Ft.
SUBFLOOR: Concrete on the First Level, Ply-wood on the Second Level.
AREA INSTALLED: Dining-Room, Family-Room, Stairs, & 3
Bedrooms, Plus Hall-way
USE & MAINTENANCE INFORMATION AT THE TIME OF INSPECTION
LITERATURE RECEIVED WITH PURCHASE: Home Builders Guide
TEMPERATURE: 70°F - 21.1° C RH 66%
ADULTS: 2 - CHILDREN: 4 - PET(S): 0
DO THEY SMOKE? No
SPOTTING AGENTS: Spot Shot
VACUUM/FREQUENCY: Hoover Upright Two Or Three Times A Week
ENTRY-MATS? Yes
SOIL: None Noticed
HEATING TYPE: Forced Air Gas
COOLING TYPE: Central - Electric
CLEANING: Do-It-Yourself & Professional
METHOD: Steam Cleaning
TYPE OF CHEMICAL: Not Given
DATE LAST CLEANED: Not Reported
TREATMENTS APPLIED: None Reported
CONSUMER METHOD: Shampoo
INSTRUCTION FOR THIS INSPECTION
Determine the cause of shedding in the master-bedroom and if the shedding is from
ultraviolet light determine whether the rays are excessive or if the fiber is defective.
THE REPORT
Site Conditions and Geographical Information
This is an owner occupied, well maintained, two-story house located in a rural and hilly
area . The master-bedroom is located on the second floor with a sliding-glass-door facing
the southeast.
BACKGROUND INFORMATION MADE TO THE INSPECTOR
The carpet was part of the purchase of this new house and in late 1997, no problems were
noticed until a black pair of pants attracted a noticeable amount of lint from the carpet.
This problem occurred next to the sliding-glass-door in the master-bedroom but no where
else. Reportedly the curtains of this sliding-glass-door are left open most of the time
and the glass has no ultraviolet protector.
Another inspection report was commissioned by this same commissioner to John Doe and the
conclusion of that report was that degradation of the fiber was due to excessive
ultraviolet rays from the sun.
DESCRIPTION OF PROBLEM AREA BY THIS INSPECTOR
In the master bedroom, the carpet had no unusual pile distortions and no variances in the
hue. Close to a sliding-glass-door near the south-east side of the room excessive shedding
was noted and the hand of the carpet felt unusually coarse. Shedding was noticed in the
front of the sliding glass door but not else where in the room.
ON-LOCATION FIELD TESTING
Numerous moisture tests were performed using a Delmhorst Moisture Sensor. This test would
indicate the presence of moisture locked up in salt compounds from urine and detergents.
The results of these tests showed no moisture in the master bedroom.
An ultraviolet light was used to draw a reflection from substances with optical
brightening agents. Yellow reflection will come from most urine stains; a blue or lavender
reflection from detergents. The result of this test revealed that there were no
reflections.
Numerous pH tests were taken using a digital type pH meter and a special low moisture
probe that made direct contact with the face yarns. This device is accurate to ± 0.1 and
was calibrated with a laboratory testing solution immediately before these tests were
made. All tests were made using distilled water with a pH of 7.0. The test results were as
follows:
shedding areas 4.9 5.1 Ave. 5
non-shedding areas 5.0 5.1 Ave. 5.05
A shedding test was repeated using the claimant's black pants as noted in the photographs.
Once again the carpet shed in the area affected by sun light near the sliding-glass-door,
but not else where.
300 hours of AATCC 16E LIGHT (XENON ARC) was performed at Independent Testing Laboratories
Inc. In Dalton Georgia on an un-installed remnant. No evidence of ultraviolet degradation
was observed and the yarn did not shed after the test.
THE ISSUE
The questions that I have been asked to address are:
1. what has caused the shedding?
2. If ultraviolet rays are responsible, are they excessive or is the fiber defective?
GUIDELINES FOR EVALUATING THE ISSUE
Excessive Shedding can occur when:
1. excessive foot or mechanical traffic
2. improper maintenance or from the use of to stiff of a brush on a vacuum cleaner
3. improper bundle wrap of the latex
4. fiber degradation from
· defects in fiber
· excessive ultraviolet light
Standards for excessive ultraviolet light and fiber degradation have not been officially
establish, but testing is normally done for 300 hours at Independent Test Laboratory.
INDUSTRY STANDARDS & DEFINITIONS
According to the IICRC FLOOR COVER REFERENCE GUIDE GLOSSARY shedding is defined as the
following:
SHEDDING - 1. The operation of forming a shed in weaving. 2. When the carpet pile is cut
during manufacturing fiber may not be removed from the surface of the carpet. With wear,
these ends work loose or shed. It is not a defect and will stop in matter of time. There
is no danger of excessive fiber loss.
THE INSPECTOR'S ANALYSIS
Since the shedding was located next to the sliding-glass-door and no where else, problems
with excessive traffic, maintenance, or problems inherent in the latex are not suspected.
Also, moisture and pH testing helps confirm that maintenance was not a factor.
Ultraviolet light is a form of energy that can degrade textiles such as carpet fibers.
When shedding is restricted to an area that is defined by the sun's path through a window
one of two possibilities.
1. The first is that the fiber itself is defective and something was wrong before the
material was made into fiber.
2. The other possibility is that the amount of light was beyond the inherent capabilities
of the fiber to resist degradation.
Whereas there is no convening authority setting official standards, there is a common
acceptance of testers and testers that 300 hours of AATCC 16E testing is ample to made a
determination.
· if some degradation was noted during the 300 hours of testing, then conclusions would
be less certain
· Similar shedding with 300 hours of testing would have been strong evidence that there
is a defect in the fiber.
Excessive ultraviolet ray are not uncommon to homes that are located high in the hills or
close to the ocean.
CONCLUSION
Shedding in the carpet in question was due to excessive ultraviolet rays based upon
laboratory testing and is not a defect in manufacturing.