EPA-650/3-74-008
FEBRUARY 1975
Ecological Research Series
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EPA-650/3-74-008
EFFECTS OF AIR POLLUTANTS
ON TEXTILE FIBERS AND DYES
by
J. B. Upham
Chemistry and Physics Laboratory
National Environmental Research Center
and
V. S. Salvin
University of North Carolina at Greensboro
Program Element No. 1AA008
and
Contract No. PH 22-68-2
ENVIRONMENTAL PROTECTION AGENCY
Office of Research and Development
National Environmental Research Center
Research Triangle Park, North Carolina 27711
February 1975
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This report is published by the Environmental Protection Agency to report information
of general interest in the field of air pollution. Copies are available free of charge—as
supplies permit—from the Air Pollution Technical Information Center, Environmental
Protection Agency, Research Triangle Park, North Carolina 27711; or, for a nominal
cost, from the National Technical Information Service, 5285 Port Royal Road, Spring-
field, Virginia 22161.
This report was prepared jointly by Mr. J. B. Upham of the U. S. Environmental Protec-
tion Agency and Dr. V. S. Salvin of the University of North Carolina at Greensboro.
The contributions of Dr. Salvin to this study were in fulfillment of EPA Contract No.
PH 22-68-2.
RESEARCH REPORTING SERIES
Research reports of the Office of Research and Monitoring, Environmental Protection
Agency, have been grouped into five series. These five broad categories were established
to facilitate further development and application of environmental technology. Elimina-
tion of traditional grouping was consciously planned to foster technology transfer and a
maximum interface in related fields. The five series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
l’his report has been assigned to the ECOLOGICAL RESEARCH Series. This
series describes research on the effects of pollution on humans, plant and animal
species, and materials. Problems are assessed for their long- and short-term influences.
Investigations include formation, transport, and pathway studies to determine the fate
of pollutants and their effects. This work provides the technical basis for setting standards
to minimize undesirable changes in living organisms in the aquatic, terrestrial, and
atmospheric environments.
EPA REVIEW NOTICE
This report has been reviewed by the Office of Research and Monitoring, EPA, and
approved for publication. Approval does not signify that the contents necessarily reflect
the views and policies of the Environmental Protection Agency, nor does mention of trade
names or commercial products constitute endorsement or recommendation for use.
Publication No. EPA-650/3-74-008
U
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CONTENTS
Page
UST OF FIGURES v
UST OF TABLES
ABSTRACT vii
Chapter
INTRODUCTION 1
2. EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS 3
PARTICULATE MATTER 3
Soiling
Effects on Natural Fibers 3
Effects on Synthetic Fibers and Blends 6
SULFUR OXIDES 7
Effects on Natural Fibers 7
Effects on Synthetic Fibers and Blends 14
NITROGEN OXIDES 17
Effects on Natural Fibers 17
Effects on Synthetic Fibers and Blends 17
OZONE 19
Effects on Natural Fibers 19
Effects on Synthetic Fibers and Blends 20
REFERENCES FOR CHAPTER 2 21
3. EFFECTS OF AIR POLLUTANTS ON TEXTILE DYES AND ADDiTIVES 23
SULFUR OXIDES 23
Potential Problem 23
Early Laboratory Investigations 23
AATCC Laboratory and Field Exposures 24
Recent Investigations 25
MTROGEN OXIDES 26
Discovery of “Gas Fading” 26
Standard Test Method 27
Laboratory investigations 27
Gas-Fired Clothes Dryers 28
Smog Study 28
AATCC Laboratory and Field Exposures 28
Cellulosic Fabrics 29
Controlled-Environment Study 29
Discoloration of White Fabrics 30
Protective Measures 30
OZONE 31
Discovery of “0-Fading” 31
Standard Test Method 33
In
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Chapter Page
Anomalous Fading During Service Trials . . 33
Permanent-Press Fabrics 34
Nylon Carpets 35
Cellulosic Fabrics 36
High-Humidity Test Method .... 36
Recent Exposures 36
REFERENCES FOR CHAPTER 3 37
4. INDUSTRIAL AND COMMERCIAL AWARENESS 41
IMPORTANCE OF COMMUNICATION 41
AWARENESS 42
Fiber Producers 42
Dye and Specialty Chemical Manufacturers . 42
Fabric Mills, Dyers, and Processors 42
Consumer-Oriented Groups 43
CONCLUSIONS 45
REFERENCES FOR CHAPTER 4 45
5. CONSUMER AWARENESS 47
INTRODUCTION 47
BACKGROUND 48
Public Awareness of Air Pollution 48
Public Information about Air Pollution Effects on Textiles 49
Characteristics of Textile Products 49
Social and Cultural Influences 50
Survey Research Techniques 50
ThE PHILADELPHIA SURVEY PLAN 51
Objectives 51
Approach 51
Survey Methodology 51
Questionnaire Design 52
Field Administration 53
THE PHILADELPHIA SURVEY FINDINGS 53
Profile of Survey Sample 53
Analysis of Responses Related to Air Pollution Factors 54
Specific Clothing and Home Furnishings Problems 57
Consumer Information Sources 57
Cross-Classification Comparisons of Areas 1 and 2 59
Socioeconomic Analysis of Air Pollution Factors 60
DISCUSSION AND CONCLUSIONS 66
General Discussion 66
Conclusions 70
REFERENCES FOR CHAPTER 5 72
6. SUMMARY AND CONCLUSIONS 75
EFFECTS ON TEXTILE FIBERS 75
EFFECTS ON TEXTILE DYES AND ADDITIVES 75
CONCLUSIONS 76
APPENDIX A. QUESTIONNAIRE-PHILADELPHIA TELEPHONE SURVEY 79
APPENDIX B. UNSOLICITED COMMENTS-PHILADELPHIA TELEPHONE SURVEY 83
lv
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LIST OF FIGURES
Figure Page
2-1 Strength Retained on Exposure of Cotton Print and Duck Fabrics at the Most (Site D)
and Least (Site F) Polluted Sites in St. Louis 10
2-2 Strength Retained on Exposure of Cotton Print and Duck Fabrics at the Most (Site 3)
and Least (Site 1) Polluted Sites in Chicago II
2-3 Relationship Between Retained Breaking Strength of Cotton Fabrics and Corresponding
Mean Sulfation Rate Measured at Selected Sites in St. Louis 12
2-4 Relationship Between Retained Breaking Strength of Cotton Print Cloth Samples and Mean
Sulfur Dioxide Concentration for 5-Month Exposure at Three Chicago Sites 13
2-5 Breaking Strength Retained for Sulfuric Acid Treated Print Cloth Exposed for 50 Flours
at Stated Conditions 14
2-6 Breaking Strength Retained for Sulfurous Acid Treated Print Cloth Exposed for 50 Hours
at Stated Conditions 15
LIST OF TABLES
Table Page
2-1 Cellulose Fluidity and Breaking Strength for Cotton Yarn Exposed Outdoors
2-2 Breaking Strength of Cotton Fabrics Seasonally Exposed Outdoors in Tallahassee
and Charleston 8
2-3 Effect of Sulfur Dioxide and Sunlight on Cotton Fabric Samples
24 Mean Breaking Strength of Unaged Fabrics and Fabrics Aged 30 Days Following
Exposure to a Humid Sulfur Dioxide-Polluted Atmosphere at Two
Temperature Levels 13
2-5 Breaking Strength of Cotton Yarn Samples Exposed to Air and Sunlight in
Berkeley, California 18
2-6 Air Pollutant Levels and Weather Measurements 18
4-1 Customer Complaints About Fading on Women’s Dresses 44
5-1 Sample Response Rate 53
5.2 Socioeconomic Profile of Survey Sample 55
5-3 Analysis of Responses to Air Pollution Survey 56
54 Summary of Textile Problems Documented in the Survey 58
5-5 Respondents Experiencing Selected Textile Problems Potentially Caused by Air Pollution 59
5-6 Consumer Knowledge of Air Pollution Effects on Textiles and Sources of Information 60
5-7 Analysis of Air Pollution Factors: Comparison of Areas 1 and 2 61
5-8 Analysis of Textile Problems: Comparison of Areas I and 2 62
5-9 Relationships Between Education and Responses to Selected Air Pollution and Textile
Questions 63
V
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Table Page
5-10 Relationships Between Family Income and Responses to Selected Air Pollution and
Textile Questions 65
5-11 Relationships Between Age and Responses to Selected Air Pollution and Textile
Questions 66
5-12 Relationships Between Length of Residence and Responses to Selected Air Pollution
and Textile Questions 67
5-13 Relationships Between Family Size and Responses to Selected Air Pollution and Textile
Questions 69
vi
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ABSTRACT
This document presents a comprehensive survey of the damaging effects of air
pollutants (particulates, sulfur oxides, nitrogen oxides, and ozone) on textile fibers
and dyes and the results and assessment of a limited-scale public-opinion survey, designed
primarily to measure consumer awareness of the detrimental effects of air pollution on
household textile products. Many research investigations are discussed in detail, and
numerous references are cited.
The findings of the survey supported the contention that air pollution is a sig-
nificant problem for the textile industry and for many consumers. Major problems on
which the survey concentrated include: (1) excessive soiling of fabrics; (2) loss in
strength of cellulosic and nylon materials by acids derived from sulfur oxides; (3) fading
of certain dyed cellulosic, acetate, and nylon fabrics by nitrogen dioxide and/or ozone;
(4) yeilow discoloration of undyed white fabrics by nitrogen dioxide; (5) fading of
permanent-press polyester/cotton fabrics by ozone; and (6) fading of certain dyed
nylon carpets by ozone. The public opinion survey revealed that consumer awareness of
the major air pollution effects on household textile products is not only poorly established
but generally lacking.
Key Words: effects-materials, textiles, textile dyes, deterioration, discoloration,
fading, soiling, particulates, nitrogen oxides, sulfur oxides, ozone, opinion surveys, social
attitudes, consumer awareness.
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EFFECTS OF AIR POLLUTANTS
ON TEXTILE FIBERS AND DYES
CHAPTER 1
INTRODUCTION
In earlier clean air legislation and, more specifically, in the Clean Air Amendments of 1970, Congress
directed the U.S. Environmental Protection Agency (EPA) to “conduct research on, and survey the results of other
scientific studies on, the harmful effects on the health or welfare of persons by the various known air pollutants.”
Welfare effects cover a wide variety of different areas including the effects on soils, water, crops, materials and
property, animals, visibility, and climate, as well as effects on economic values and personal comfort and well-being.
Damage to materials and property is an important part of welfare effects. In fact, the accelerated corrosion
of some metals by sulfur dioxide (SO 2 ), the cracking of rubber by ozone (03), and the soiling of buildings,
statuary, and personal property by particulates are all well-known examples of materials problems. The effects
of air pollution on textile products are less familiar, but a cursory review of information on this subject indicates
that such effects constitute a major problem. After such an initial investigation, materials-effects specialists con-
cluded that, since textiles comprise 8 to 10 percent of the gross national product, a thorough study of air pollution
effects on textiles was needed.
Consequently, EPA conducted a comprehensive survey to identify and document the adverse effects of air
pollution on textile fibers and dyes. To support this effort, EPA awarded a contract (PH 22.68-2) to Dr. Victor S.
Salvin, a recognized authority in this field. He collected information from a number of sources, including various
fiber producers, fabric mills, and processors; dye and chemical specialty suppliers; apparel and home furnishing
manufacturers; commercial and retail outlets; and trade associations. Also, he directed a limited scale public
opinion survey, primarily to measure consumer awareness of the detrimental effects of air pollution on household
textile products.
This document presents the results of the survey and, additionally, brings together all available technical
information on the subject of air pollution effects on textile products, providing an up-to-date picture of the total
problem. Further, it furnishes background data for use in establishing air quality criteria and for use in economic
analyses. This report may also stimulate new ideas and approaches for future research. This publication, written
in a semitechnical style, is intended to appeal to a wide range of readers, especially those associated with various
textile interests.
1
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CHAPTER 2
EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS
PARTICULATE MATTER
Soiling
Unless fabrics are exposed to the abrasive action of wind-blown particles or are soiled with highly abrasive
particles and repeatedly flexed, they are not directly deteriorated by soiling, a familiar (but aesthetically objection-
able) process in which airborne particles settle on objects. The major impact of soiling results from the need for
more frequent dry cleaning and laundering, which not only represent added expenses but, more importantly,
hasten the day when fabrics are no longer serviceable. Each cleaning cycle subjects fabrics to abrasion, heat, and
harsh detergents or solvents; all these stresses contribute to a progressive loss in fiber strength and, in some cases,
a gradual loss in color. Thus, increased soiling represents an economic loss because of the need for more frequent
cleaning, which in turn reduces the normal life expectancy of fabrics. 1
Suspended particulate matter accounts for most of the soiling that takes place on fabrics. These particles,
which for the most part range in size from 0.1 to 10 micrometers (pm) in diameter, soil fabrics by impinging on or
adhering to their surfaces. Particles of less than 0.1 pm, however, may soil by entering the capillary spaces known
to exist in fibers.
Particles deposit on fabrics in several ways, with the larger ones usually settling out under the influence of
gravity. Often, fabrics behave like a filter in that particles are deposited on them as air sweeps through the inter-
stices between fibers. Draperies and curtains may be soiled in this manner. A process known as thermal precipi-
tation causes household furnishings to soil when their surface temperatures fall below ambient air temperatures,
a common occurrence during the winter heating seasons. Fabrics made from most synthetic fibers acquire electro-
static charges and, as a result, attract airborne particles of opposite charge, producing troublesome “fog markings.”
The degree of soiling may be influenced by various factors, including temperature, relative humidity, wind speed,
and the nature and size of particles, as well as the type of fiber, construction, and finish.
Although it indirectly results in physical damage to fabrics because of the need for more frequent cleaning
and the use of harsh detergents, soiling may also affect fabrics in other ways. For example, unidentified compo-
nents in soils appear to accelerate the photochemical breakdown of some textile fabrics. (Supporting research will
be presented later.) Also, metallic components of soils may have diverse effects on fabrics, and some, such as iron
and zinc, can serve as catalysts that promote the oxidation of sulfur dioxide (SO 2 ) into harmful acids. 2 Others,
such as chromium, vanadium, and manganese compounds, are known to offer some degree of protection to fabrics
against the damaging effects of sunlight. Soiled fabrics, therefore, may undergo less photochemical degradation
than clean fabrics. Accordingly, the total effect of soiling is complex, the net damage to fabrics depending on the
chemical composition of the soiling particles and the ambient environment.
Effects on Natural Fibers
Natural fibers consist mainly of the cellulosics (cotton and viscose rayon) and wool, but also include such
fibers as silk, flax, hemp, and jute. (Viscose rayon is a man-made fiber, but because it is manufactured from wood
3
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pulp and has properties similar to those of cotton, it will be grouped with the natural fibers.) Research on the effects
of airborne particles on natural fibers has been generally confined to cotton, mainly because cotton has been the
workhorse of the textile industry, has many applications, and is less resistant to overall environmental degradation.
Scientists at the Shirley Institute in England made one of the earliest attempts to assess the amount of
tendering that smoke-laden air produces in textile fabrics. 3 In a limited field study, they exposed lightweight
cotton fabric samples to the prevailing atmosphere at a single site on the roof of the Shirley Institute building.
The samples were sheltered from rain and direct sunlight. Exposure lasted 12 weeks (January to April 1954), and
samples were withdrawn for testing at periodic intervals. The investigators did not measure pollution, but did note
that soiling varied considerably during the exposure period. Prior to exposure and after each exposure interval,
soiling, tensile strength, sulfuric acid content, and fluidity were measured on the cotton samples.
Fluidity, an important property of textiles, is essentially an indirect measure of a polymer’s average molecular
weight. Chemists measure fluidity by dissolving polymers in suitable solvents and measuring the fluidity (reciprocal
of viscosity) of the resulting solutions. Scientists can make use of changes in fluidity to detect changes in a poly-
mer’s molecular weight. Thus, an increase in fluidity indicates a reduction in the average molecular weight of a
polymer. Such chemical changes are important because they are accompanied by changes in tensile strength and
other physical properties. For example, extraneous environmental factors such as sunlight, heat, and contamination
cause some polymers to degrade chemically. Changes in fluidity measure this undesirable effect. Fluidity measure-
ments also allow scientists to distinguish between chemical degradation and physical degradation resulting from
biological attack. In both cases, polymers lose strength, but physical degradation is the result of ruptured fibers
rather than changes in molecular structure. Thus, fluidity values for physically degraded fibers remain essentially
constant, and loss in strength is attributed to biological factors.
Results of the Shirley Institute cotton exposure study showed that, as exposure proceeded, the cotton samples
became dirtier and progressively lost strength; fluidity increased, indicating chemical degradation; and sulfuric
acid content increased during the first 8 weeks and then dropped off slightly. After 12 weeks, the cotton samples
lost 59 percent of their original strength. Despite these results, the full significance of this limited study is clouded
because the investigators did not simultaneously expose control samples to clean air at similar conditions of
temperature, humidity, and sunlight. Without controls, pollution damage can not be separated from weathering
damage. Nevertheless, the sulfuric acid content of the exposed samples indicates that acid probably caused much
of the degradation. It is not known whether this acid resulted from the hydrolysis of inorganic sulfate particles
or whether it came from airborne acid-aerosols. Notwithstanding the shortcomings of the study, however, the
results strongly suggest that air contaminants were important contributors to the chemical degradation of the
exposed cotton samples.
Rees 4 conducted several studies in which he assessed various factors that affect soiling. He exposed a series
of scoured and bleached woven cotton fabrics to circulating air containing a controlled amount of dispersed
activated-charcoal powder. Fabric construction varied from open porous plain cloth to tightly woven canvas
material. The study revealed that airborne particles deposited more readily on porous open-weave fabrics than
on closely woven low-porosity fabrics. In his study of textile soiling by thermal precipitation, Rees showed that
the greater the temperature difference between fabric surfaces and ambient air, the greater the extent of soiling.
He also investigated electrostatic soiling and found that soiling is heavier on positively charged fabrics (indicating
a surplus of negative airborne ions) than on those charged negatively, with both showing much greater soiling than
uncharged fabrics.
Morris and Wilsey 5 studied the effect of three soiling agents on the photochemical degradation of cotton.
They impregnated some cotton yarn samples with an airborne soil, some with ground soil (clay, loani), and some
with lignin derived from the organic portion of the ground soil. The yarn samples impregnated with airborne soil
retained enough soil to increase the weight of the yarn about 5 percent. A group of soiled samples, along with un-
soiled controls, were exposed in a Fade-Ometer (carbon-arc light source) for 640 hours. The investigators also
aged a similar group of samples for 640 hours at 21°C in the absence of ultraviolet light. Degradation was evaluated
by measuring the fluidity and breaking strength of the yarn samples. Fluidity values for the aged samples, both
soiled and unsoiled, did not differ, thus showing that the soil treatments did not accelerate degradation. Of the
4 EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
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samples exposed in the Fade-Ometer, however, those impregnated with airborne soil showed a 17 percent increase
in fluidity over the unsoiled control samples. This result suggests that some component in the airborne soil
accelerated the photochemical degradation of the cotton fibers by serving as a photosensitizing agent. Fluidity values
for the samples impregnated with lignin and ground soil were essentially the same as for the unsoiled control
samples, thus lignin and ground soil produced no photosensitizing effect. Although increases in fluidity are
normally accompanied by losses in breaking strength, this study did not follow this pattern. The investigators
found no significant differences in strength between the soiled and unsoiled samples for either the aged samples
or those exposed to ultraviolet light in the Fade-Ometer.
Morris and Young 6 followed up the Fade-Ometer exposures with a field study. They impregnated cotton
yarn samples with the same airborne soil that accelerated the photochemical degradation of cotton during the
Fade-Ometer exposures. These soiled samples, along with unsoiled control samples, were mounted in a glass-covered
cabinet, designed to allow free access of ambient air, and were exposed outdoors (in Berkeley, California) for four
consecutive 3-month periods (84 days), as well as consecutive combinations of these periods. Some samples were
exposed to direct sunlight while others were shaded. The investigators assessed degradation by measuring fluidity
and breaking strength of the cotton samples. Table 2-1 presents data for the various exposure periods. During
exposures to sunlight (unshaded conditions), the soiled samples underwent a significantly greater increase in fluidity
than the unsoiled samples, thus confirming the photosensitizing effect (of this particular airborne soil) found during
the Fade-Ometer exposures. In contrast, measurements showed little difference between fluidity of soiled and
unsoiled samples shaded during exposure. Exposure to sunlight also showed that the soiled samples developed a
greater loss in breaking strength than the unsoiled samples. The Fade.Ometer results did not show any difference
in strength between soiled and unsoiled samples. Sample size did not permit breaking-strength measurements on
shaded samples. By comparison, the 3-month outdoor unshaded exposures were more severe than the Fade-Ometer
exposures (640 hours). Since in both exposures the investigators exposed the samples to about the same number
of light-hours, the increased severity may have been caused by greater intensity of sunlight, or by some spectral
component in the sunlight that is missing from the carbon-arc light source, or by a combination of these factors.
Both exposures clearly show, however, that the airborne soil used by the investigators accelerated the degradation
of cotton when it was exposed to ultraviolet light.
Table 2-1. CELLULOSE FLUIDITY AND BREAKING STRENGTH
FOR COTTON YARN EXPOSED OUTDOORS
Exposure
period
Number
of days
Cellulose fluidity, rhesa
Breaking strength, g
Unshaded
Shaded
Unshaded
Soiled
Unsoiled
Soiled
Unsoiled
Soiled
Unsoiled
Jan-Mar
Apr—Jun
Jul—Sep
Oct-Dec
Jan—Jun
Jan—Sep
Jan-Dec
84
84
84
84
168
252
336
17.46
18.82
20.38
17.14
29.20
35.66
38.54
9.78
13.32
14.54
10.64
20.31
27.06
32.37
3.12
2.48
3.59
2.85
5.26
11.65
14.96
2.65
4.46
5.82
3.76
6.75
12.62
18.70
298
246
248
280
152
78
59
348
296
274
335
202
144
97
Control
-
0.58
599
aReciprocal poises.
Effects of Air Pollutants on Textile Fibers 5
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Morris et al. 7 also studied the effect of airborne soil on the photochemical degradation of wool. The soil
was similar to that used in the previously described cotton exposures. After treatment with the soil, the wool
samples were said to have a “lightly soiled appearance.” Results indicated that the soilhad a moderate photo-
sensitizing action on the wool. For example, after 160 hours of exposure in a Fade-Ometer, the soiled material
had decreased 63 percent in strength, compared with 51 percent for the unsoiled material. The strength of soiled
and unsoiled wool samples did not appreciably change when these samples were exposed in the dark for 160 hours
under standard conditions (65 percent relative humidity, 21°C).
Window curtains and draperies are particularly vulnerable to environmental deterioration because they are
subjected during their use to more destructive conditions than most fabrics. 8 While these items are woven from
practically any fiber or combination of fibers, much of the observed accelerated deterioration has occurred to
cellulosic fabrics. Deterioration and yellow streaks develop mainly along the exposed outer folds of curtains and
draperies. Much of this damage is caused by sunlight, but an important contributing factor is air pollution, including
particulate pollutants.
Effects on Synthetic Fibers and Blends
Because of public acceptance of and demand for synthetic fIbers, the textile industry now consumes more
fibers of this type than cotton. This consumption is due mainly to the high-volume use of nylon and polyester
fibers. With increased consumption of synthetic fibers, soiling problems are of even greater importance because
normal laundering does not remove soil from most synthetic fibers as easily as from natural fibers.
Man-made fabrics are more difficult to clean because of the nature of fibers themselves. Most natural fibers,
such as cotton and wool, are hydrophiic and, thus, readily absorb detergent solutions, which emulsify and disperse
the soil. On the other hand, most synthetic fibers are hydrophobic and, thus, do not readily absorb detergent
solutions. Soil removal is difficult with synthetic fibers, therefore, since surface oil and soil are not easy to emul-
sify or suspend unless detergents properly wet the fibers.
Sooty soils are particularly troublesome because they are tenaciously bound to fiber surfaces. These soils,
which contain unsapomfiable hydrocarbons, are typically found in Los Angeles-type air pollution. Sooty soils are
not easily removed from man-made fibers by laundry detergents but may yield to dry cleaning. Nylon, despite
repeated laundering, takes on a yellowish cast when exposed to such soils. 9
Most synthetic fibers have another disadvantage that contributes to the soiling problem. Unlike natural fibers,
man-made fibers have properties of high electrical resistance and low moisture absorption. They, therefore, easily
acquire electrostatic charges by means of friction and become soiled by attracting oppositely charged airborne
particles. The degree of soiling by this mechanism depends on the nature of airborne particles, the type of fiber,
the surface topography of the fiber, and the finish applied to the fabric.
The popular permanent-press fabrics of polyester and cotton contain finishes that enhance various fabric
properties. Finish components include shape-retention resins, softeners, catalysts, and soil-release (wetting) agents.
Unfortunately, most of the finish components attract soil particles and hold them tenaciously. This factor, together
with the electrostatic attraction that polyester fibers possess, intensifies the overall soiling problem for these
important fabrics.
Soiling problems associated with man-made fibers have been the subject of considerable research. To reduce
the soiling tendency of these fibers, scientists are continually experimenting with fiber modifications and searching
for effective soil-release finishes.
Morris and Mitchell 10 studied the effect of an airborne soil on the photochemical degradation of nylon 66
yarn. Using an airborne soil similar to that used in previously described cotton studies, the investigators found
6 EFFECI’S OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
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that the soil had a slight phorosensiti7ing action on the nylon. Upon exposure in a Fade-Ometer for 160 hours. the
soiled nylon yarn lost 71 percent of its original strength while the unsoiled samples lost 62 percent. After exposure
for 320 hours, the soiled yarn lost 86 percent of its strength while the unsoiled samples lost 81 percent. Cout ol
samples aged in darkness under standard conditions(6f percent relative humidity. 21°C) for like exposure periods
showed no significant loss in strength. Control samples heated for like exposure periods in a circulating air oven
at 63°C (the mean operating temperature of the Fade-Ometer) also showed no significant loss in strength. While
the study clearly showed the pronounced damaging effect of ultraviolet light on nylon, the study also showed that
this particular soil mildly accelerated photochemical degradation.
SULFUR OXIDES
Sulfur dioxide (SO 2 ) is a gaseous byproduct formed during the combustion of fuels containing sulfur and
is a major atmospheric pollutant. Industrial operations and power plants are the principal sources of SO 2 emissions.
Effects on Natural Fibers
The known sensitivity of cellulosic fibers to acid deterioration has prompted a number of researchers to
investigate the possible damaging effects of atmospheric contaminants. Interest has centered mainly on SO 2
because of its eventual conversion to sulfur acids. These acids have been responsible for reducing the life expect-
ancy of clothes and of such household items as curtains, carpets (backing yarns), and linen products. 11
One of the earliest (1928-29) studies on she damaging effects of air pollution on textile fabrics was an inves-
tigation by Wilkie 2 to determine why laundered cotton fabrics that were dried outdoors in winter in New England
frequently underwent excessive deterioration. This peculiar problem had been of concern to residents of New
England for a number of years and had come to be known as “winter damage.” Deterioration occurred only in
New England and only in the winter and was largely unpredictable. After examining many case histories, Wilkie
concluded that winter damage was caused by sulfuric acid formed in the damp fabrics by oxidation of absorbed
SO 2 , which was present in the ambient atmosphere. Oxidation is accelerated by trace amounts of certain sub-
stances such as iron, spent bleach, and acetic acid, all of which may occur in laundered fabrics. As fabrics dry, the
acid becomes concentrated in the areas that dry last. Subsequent ironing causes rapid deterioration and the fabric
becomes weak. Damage occurs in winter because S02 from burning fuel is more prevalent then and because clothes
do not dry well on cool, damp,or overcast days; thus, they remain moist longer and absorb more SO 2 . Winter dam-
age is found principally in New England because the water is exceptionally soft and, therefore, free from bases
that would neutralize acids. Wilkie was able to reproduce various degrees of winter damage in the laboratory by
exposing cotton fabrics, with and without special treatments, to repeated drying-ironing cycles. The drying opera-
tion consisted of exposing moist fabrics for about 24 hours to air initially contaminated with 2620 micrograms
per cubic meter ( tg/m 3 ) SO 2 , or 1 part per million (ppm).
In the mid-1940’s, Race 12 conducted several field studies in which he exposed cotton yarn samples(unpro-
tected) to ambient air in the highly industrialized city of Leeds, England. He first exposed yarn during 3 consecu-
tive summer months (June, July, and August), followed by a similar exposure the following winter (December,
January, and February). For each seasonal exposure, breaking strengths were measured after 4, 8, and 12 weeks.
The results showed that the cotton yarn underwent greater degradation in winter than in summer. Inasmuch as
sunlight has a strong deteriorating effect on cotton, these results suggested an apparent anomaly because sunlight
is more intense and the number of sunlight hours is greater in summer than in winter.
Race next exposed yarn samples at the same site on a monthly basis for 1 year. He again found a greater ‘oss
in breaking strength during the winter months (about 23 percent) than during the summer (about 17 percent).
Furthermore, the smallest strength losses (about 15 percent) occurred in the spring and fall. Race also found an
apparent relationship between monthly strength-loss values and the corresponding monthly pH measurements of
both rainfall and the atmosphere. On the basis of these results, Race concluded that sulfuric acid aerosols, derived
Effects of Air Pollutants on Textile Fibers 7
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from SO 2 discharged into the atmosphere by domestic coal-burning heating systems, were responsible for the
excess damage. The frequent accumulation of fog during winter further intensified the hostile nature of the atmo-
sphere, since fogs prevent dispersion and allow contaminants to concentrate in the vicinity of the sources. In sup-
port of his conclusion, Race estimated that domestic and industrial coal-burning sources in Leeds release almost
three times as much SO 2 in winter as in summer. He did not, however, actually measure the levels of SO 2 in the
atmosphere.
Pomroy and Stevens 13 investigated the effects of nonspecific air pollution on the deterioration of drapery
lining materials. The materials included four cotton and two acetate-rayon fabrics purchased at several large
department stores. Two geographically different exposure sites were selected: Tallahassee, Florida, which has
no industrial pollution but has a humid climate and receives intense sunlight; and Charleston, West Virginia, which
is an industrial city—with much air pollution—located in a valley amid mountains. The investigators exposed the
fabric samples both indoors and outdoors for four consecutive 3-month seasonal periods (May 1960 through
April 1961), and also exposed them for cumulative periods of 6, 9, and 12 months. Deterioration was assessed
by measuring breaking strength, with the results expressed as a percentage of the original breaking strength retained.
During the seasonal outdoor exposures, fabrics underwent a greater loss in strength in Charleston than in
Tallahassee, despite the more intense sunlight in Tallashassee (Table 2-2). Deterioration was greatest in summer
(May through July) and least during winter (November through January), which was contrary to what Race found.
Race’s findings, however, may be explained by noting that sunlight in England is less intense because of latitude,
and pollution levels are far more severe in winter than in summer; air pollution levels in Charleston are fairly consist-
ent throughout the year. Furthermore, in making site-to-site comparisons of the exposure results, the investigators
recognized that weather conditions for the most part were dissimilar and that their analyses, therefore, were subject
to some degree of uncertainty. They attempted to make these comparisons more valid by including in their analyses
background information obtained from weather bureaus. Despite the differences in weather, the investigators con-
cluded that the industrial air pollution prevailing in Charleston was a significant factor in causing the drapery lining
materials to deteriorate during the outdoor exposures. The indoor exposure results, however, were generally erratic,
although air pollution appeared to be a factor in the cumulative exposures of cotton fabrics (but not acetate-rayon)
when sunlight was minimal.
Table 2-2. BREAKING STRENGTH OF COTTON FABRICS SEASONALLY
EXPOSED OUTDOORS IN TALLAHASSEE AND CHARLESTON 13
Exposure
site
Breaking strength retained, percent
May-July
August-October
November-January
February-April
Ta11ahassee
Charleston
58
40
73
56
79
63
74
53
Although they concluded that air pollution was a significant factor in causing deterioration, the investigators
did not measure air pollution or attempt to single out which pollutant or pollutants were causing most of the
damage. The latter would admittedly be difficult because the nature of pollution in Charleston is known to be
complex. On the basis of documented pollution measurements, however, one may surmise that acids, both inor-
ganic and organic, caused much of the damage; acids are known to be detrimental to ceflulosics. Sulfuric acid,
resulting from the hydrolysis of sulfate particles, may have been the major culprit since sulfate particles make up
about 11 percent of the total particulate matter found in the ambient air of Charleston. 14 Airborne sulfate particles
are normally the end products of a series of atmospheric reactions involving SO 2 .
Noting that some textile fabrics exposed at outdoor sites having equal sunlight intensity lost more strength
at urban and industrial sites than at rural sites, Little 15 postulated atmospheric SO 2 as a possible cause and
8 EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
-------
conducted simple tests to assess this supposition. He exposed sealed jars containing cotton samples to sunlight.
The relative humidity inside the jars was 90 percent, and some jars contained a small quantity of SO 2 (amount not
specified) while others contained clean air. The cotton samples in jars containing SO 2 developed considerable
deterioration (evidenced by an increase in fluidity) after only a few days of exposure to sunlight; samples kept in
darkness did not deteriorate (Table 2-3).
Table 2-3. EFFECT OF SULFUR DIOXIDE AND SUNLIGHT
ON COTTON FABRIC SAMPLES
Exposure time
Increase in fluiditya
Clean air
Air containing SO 2
Kept in darkness
Exposed for 4 days
Exposed for 10 days
0
1.8
3.5
0.2
11.8
18.4
aihe published research does not state the units, but
normally fluidity is expressed as rhes (reciprocal
poises).
These results prompted Little 15 to carry out indoor-outdoor exposures of bleached cotton fabrics at an
urban site known to be contaminated with SO 2 . Five-month results showed that the rate of degradation for the
outdoor samples was three times that of the indoor samples, but pH values (about 3.6) for both samples were
similar. Little concluded that, while these pH values were low, they were not low enough to indicate the presence
of sufficient amounts of strong acid to produce the degree of degradation measured. He proposed that acid attack
was an unlikely cause of increased degradation and that sunlight, therefore, does not activate acid hydrolysis of
cellulosics. Since the accelerating effect of sunlight must involve some other reaction, Little proposed that sunlight
stimulates the oxidation of sulfur dioxide (SO 2 ) to sulfur trioxide (SO 3 ), and that SO 3 accelerates the normal
photochemical oxidation of cellulose by atmospheric oxygen.
In the fall of 1961, Little and Parsons 16 conducted a field study in which they exposed cotton, nylon, and
polyester fabrics at eight sites in the United Kingdom. The nominal weights of the fabrics were similar, and all
were unprotected during the 12-month outdoor exposure period. Results, in terms of loss-in-strength measure-
ments, varied considerably with location. At rural clean-air sites, cotton was more resistant than nylon, but roughly
equivalent to polyester. In urban and industrial areas, however, polyester and, to a lesser extent, nylon retained
more strength than cotton. Although air pollution was not measured, it is well-known that most English industrial
areas have above average levels of air pollutants, including SO 2 , which conceivably, could have played an important
role in the deterioration of the cotton fabrics. Pollution in the fonii of particulate matter, however, can have a
benetIcial effect by reducing the amount of transmitted ultraviolet light. In reviewing this exposure study, Clibbens 17
observed that cotton had a greater range of deterioration than the synthetic fabrics. Moreover, he noted that
polyester deterioration tended to be related to the amount of transmitted light energy, but that it was not signifi-
cantly related to ambient air pollution. For nylon, the relationship between deterioration and light energy was
less positive, and air pollution, therefore, may have exerted a small effect.
In further attempts to assess the role air pollution plays in degrading cotton textile fibers, Brysson et al. 18
conducted outdoor exposure studies that allowed the investigators to define more precisely the relationship
between degrees of damage and corresponding ambient air quality. They exposed cotton fabrics at selected sites
within metropolitan areas. Pollution levels differed from site to site, and, at most sites, one or more parameters of
pollution were simultaneously measured during exposure. Because exposures were conducted within one metro-
politan area, the scientists considered all sites to be similar meteorologically. This approach permitted the
Effects of Air Pollutants on Textile Fibers 9
-------
investigators to assume that the damaging effects of sunlight and other weather factors were essentially uniform at
all sites. Data from nonpolluted control sites, therefore, became baselines for damage comparisons, and all damage
found to be greater than that measured at control sites was attributed to air pollution. In an effort to minimize the
degrading effect of sunlight, the exposure racks were oriented facing north at all sites.
Brysson et al. 18 conducted separate studies in the metropolitan areas of St. Louis, Missouri; and Chicago,
Illinois. Exposures in both cities lasted 1 2 months, and fabric samples were periodically removed at specified
intervals and tested. In both studies, the investigators found an apparent relationship between air pollution and
loss in strength. The most deterioration in samples occurred at heavily polluted sites and the least occurred at the
low-pollution sites. Additional support for the relationship between air pollution and sample deterioration was
provided when it was shown that biological agents played an insignificant role in causing degradation. Figures 2-1
and 2-2 graphically illustrate the relationship between exposure time and strength retention for cotton fabrics that
showed the most and the least loss in strength.
Brysson et al. 18 also attempted to correlate losses in strength with individual pollutant measurements.
Pollution data for St. Louis included periodic 24-hour measurements of suspended particulate matter and monthly
dustfall and sulfation measurements. (Sulfation measurements provide a useful index of the activity of atmospheric
sulfur compounds, especially SO 2 .) The investigators found a strong correlation (based on six observations) between
retention of breaking strength and sulfation (Figure 2-3). For the heavier cotton duck cloth, the correlation coef-
ficient for the 12-month exposure was 0.95. The correlation coefficient for the thinner cotton print cloth was
0.96; this value is based on S months of exposure since this period was the longest for which samples from all sites
had a measurable degree of retained breaking strength. The relationship between deterioration and suspended
a)
a)
U i
I-
Ui
=
I-
Ui
I-
C’)
U.’
Figure 2-1. Strength retained on exposure of cotton print and duck fabrics
at the most (site D) and ‘east (site F) poUuted sites in St. Louis.
MONTHS EXPOSED
10
EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
-------
w
I-
w
I—
L U
Figure 2-2. Strength retained on exposure of cotton print and duck fabrics
at the most (site 3) and ‘east (site 1) poHuted sites in Chicago.
particulate matter, while substantial, was more scattered than that between deterioration and sulfation. No corre-
lation was found for dustfall and deterioration. In Chicago, two pollutants were measured: suspended particulate
matter and SO 2 . Because the latter was measured at only three of five exposure sites, however, statistical correla-
tions could not be made. Nevertheless, plots of breaking strength versus mean SO 2 levels (Figure 2-4) showed an
apparently strong relationship, but plots of suspended particulate matter were inconclusive.
Although the exposure studies of Brysson et al. 18 lacked the necessary requisites for a thorough statistical
analysis, the results do show an apparent relationship between loss in strength of cotton fabrics and air pollution.
Of the pollutants measured. SO 2 appears to be the one most responsible for causing damage.
Brysson et a!. ’ 9 also conducted laboratory studies in which they artificially treated samples of cotton print
cloth with dilute concentrations of sulfuric or sulfurous acids and then exposed them to three controlled environ-
ments: 50 hours at room temperature (about 20°C) and darkness: 50 hours at 48°C and darkness; and 50 hours
in a Fade-Ometer (carbon arc), inwhich the face temperature of the samples was 48°C. As can be seen from Figures
2-5 and 2-6, only the sulfuric acid caused degradation at the levels tested; apparently, low concentrations of
sulfurous acid do not attack the cotton print cloth, nor do they convert appreciably to the higher oxidation state
under the conditions of exposure. The data also show that artificial sunlight accelerates the degrading effect of
sulfuric acid, and, according to the researchers, the degradation is greater than can be explained by the action of
sunlight alone.
Later studies by Fye et al. 20 showed that, in the absence of artificial sunlight, cotton and rayon do not
significantly deteriorate when they are continuously exposed for 90 days (under dynamic conditions) to a
MONTHS EXPOSED
Effects of Air Pollutants on Textile Fibers
11
-------
-
C •4
E
c .’J
0
C-.)
E
0
I-
U-
-J
C ,)
uJ
Figure 2-3. Relationship between retained breaking strength
of cotton fabrics and corresponding mean sulfat ion rate
measured at selected sites in St. Louis.
controlled environment containing 5350 pg/rn 3 (2 ppm) SO 2 at 19°C and 75 percent relative humidity. The inves-
tigators concluded that lack of deterioration indicated that little or no SO 2 was converted to sulfuric acid, and
that this result was probably attributable to the absence of sunlight during exposure.
In follow-up research, Long and Savile 21 continuously for 30 days in the absence of light, exposed cotton,
acetate, and triacetate fabric specimens to air containing 5350 pg/rn 3 (2 ppm) SO 2 . Two controlled exposure
conditions were used: 95 percent relative humidity at 3 3°C, and 90 percent relative humidity at 19°C. The hives-
tigators confirmed the presence of acid in the exposure chambers. Following exposure, breaking strength of half
of the specimens was determined; the remaining specimens were tested after they had aged for an additional 30
days. As shown in Table 2-4, none of the fabrics showed pronounced deterioration despite the relatively severe
exposure conditions. Acetate showed the most loss, about a 7 percent reduction in strength. The absence of light
may have been a factor in the relative lack of deterioration.
Zeroman 22 carried out laboratory exposures that more closely approached actual service conditions. He
exposed fabric samples of cotton (3.0 ounces per square yard), viscose rayon (4.2 oz/yd 2 ), and high-wet-modulus
rayon (2.6 oz/yd 2 ) for 7 days to clean air (filtered through charcoal and soda lime) and to clean air containing 250
pg/rn 3 (0.1 ppm) SO 2 . Both environments included continuous exposure to artificial light (xenon arc) and a water
spray turned on for 18 minutes every 2 hours. The dry bulb temperature was 40°C, and the relative humidity was
maintained at 50 percent when the water spray was off. Under these controlled-environment conditions, loss in
strength for all the fabrics exposed to clean air averaged 13 percent, while the fabrics exposed to air containing SO 2
averaged 21 percent.
0 10 20 30 40 50
BREAKING STRENGTH, percent
12
EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
-------
Table 2-4.
30 DAYS
Figure 2-4. Relationship between retained breaking strength
of cotton print cloth samples arid mean sulfur dioxide concen-
tration for 5-month exposure in three Chicago sites.
MEAN BREAKING STRENGTH OF UNAGED FABRICS AND FABRICS AGED
FOLLOWING EXPOSURE TO A HUMID SULFUR DIOXIDE-POLLUTED
ATMOSPHERE AT TWO TEMPERATURE LEVELSa
(pounds)
Fiber
Control
High temperature, 33°C
Low temperature, 19°C
Unaged
Aged
Unaged
Aged
Acetate
Triacetate
Cotton
Acrylic
Modacrylic
Nylon
Polyester
23.08
16.44
35.78
45.18
74.96
114.72
57.12
21.50
16.94
35.32
43.45
76.96
110.16
54.62
21.38
16.48
33.52
44.80
78.02
111.20
56.16
21.26
16.04
33.76
40.94
77.90
110.64
55.12
20.78
15.56
36.42
43.60
76.58
111.82
54.22
a 502 present at 2 ppm.
0
I .-
I .-
LU
0
C-,
c’.J
0
C ,)
LU
BREAKING STRENGTH RETAINED, percent
Effects of Air Pollutants on Textile Fibers
13
-------
‘3
0
w
I —
u- I
I—
u - I
I-
C ,)
u - I
Figure 2 -5. Breaking strength retained for sulfuric acid treated print
cloth exposed for 50 hours at stated conditions.
Textile chemists do not agree on the mechanism by which cellulosic fabrics are degraded during atmospheric
exposure. Some believe that all degradation is a process of oxidation by air and that the oxidation of airborne con-
taminants may set up chain reactions that accelerate the normal photochemical oxidation of cellulose by atmospheric
oxygen; others attribute it to acid hydrolysis, which they claim causes various degrees of depolymerization in the
fibers, resulting in lowered breaking strengtk The remaining scientists take the view that degradation is a combi-
nation of both processes. Regardless of the mechanism, some air pollutants, especially SO 2 , are important factors
in causing the degradation of cellulosic textiles.
Effects on Synthetic Fibers and Blends
Research related to the effects of air contaminants on synthetic fibers has been limited, probably because of
the notion that synthetic fibers are chemically stable. This presumption may be inaccurate, especially when possible
synergistic effects are considered.
The first totally man-made fiber was nylon, a material possessing excellent resistance to most chemicals,
though it is seiisitive to strong acids. This sensitivity was vividly brought to light in 1941,2 years after nylon ho-
siery was marketed, when an unprecedented outbreak of runs in women’s stockings occurred in Washington, D. C.
On investigating the problem, the National Bureau of Standards 23 interviewed the women who had worn the
stockings and found that the numerous runs appeared suddenly, all at about the same time of day. The breaks
responsible for these runs occurred predominately in the ankle and lower-leg areas. Tiny dark specks of matter
could be seen with the unaided eye at most of the breaks. Microscopic examination showed that the broken fibers
0.075 OdDO
H2S0 4 ON FABRIC, percent
14
EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
-------
I I I I
ROOM TEMPERATURE, DARKNESS
- 0 -
—0 - -
48° C, DARKNESS
48° C, FADE-O4V1ETER
80
U. ’
w
I—
U.’
I-
U.’
20—
I I I I I
0.025 0.050 0.075 0.100 0.125 0.150
H 2 SO 3 ON FABRIC, percent
Figure 2-6. Breaking strength retained for sulfurous acid treated print
cloth exposed for 50 hours at stated conditions.
clearly had been acted on by a chemical at the point of rupture and that they showed no sign of having been severed
by cutting or abrasion. Furthermore, chemical tests showed the fibers to be strongly acidic in the vicinity of the
particles and breaks, but nowhere else. The acid was identified as sulfuric acid. Runs were attributed to the action
of acid sorbed by airborne particles that deposited on the stockings. DuPont 24 conducted additional studies and
found that outbreaks of runs were caused by a combination of adverse factors: high air.pollution levels, high
humidity, and, in many instances, poor air circulation. The source of the sulfuric acid was generally attributed to
atmospheric SO 2 .
Nylon stockings are especially sensitive because they are ultrasheer, are knitted rather than woven, and are
under constant tension when worn so that the slightest break in threads may start runs. On the other hand, woven
nylon fabrics used in such clothing items as blouses and shirts are not sheer and are comparatively free from stress:
thus, they are not so easily damaged by acid pollutants.
Mthough Washington, D. C., was the scene of the first outbreak of runs in nylon stockings, other cities also have
experienced incidents. New York. Chicago, Los Angeles, Jacksonville. and Nashville, for example, have reported
such outbreaks. 24 Similar incidents have occurred in foreign countries. 25 ’ 26 Frequently, outbreaks take place in
localized areas such as in the vicinity of chemical plants or railroad stations. Many incidents go unreported, however,
because they are not concentrated in a single area, and women tend to place the blame on hosiery manufacturers. 27
Travnicek 25 investigated the effects of air pollution on synthetic fibers by conducting laboratory studies in
exposure chambers. He confirmed that damage occurs to nylon fibers from S0 2 -laden soot by exposing nylon
Effects of Air Pollutants on Textile Fibers 15
-------
fibers to activated charcoal saturated with SO 2 . He found that this artificial soot must usually be activated by
heat or light in the presence of high humidity to produce damage. He also observed that damage to more acid-resistant
fibers (polyesters, polyolefins) was less pronounced, but that a distinct weakening did occur under these conditions.
Unfortunately, it is impossible to assess this research fully because Travnicek did not delineate his methodology
or quantitatively define the exposure conditions and results.
Fye et al. 2 o continuously exposed polyester, 65/35 polyester-cotton blend, and nylon fabrics to a controlled
environment (dynamic conditions) containing 5350 jig/rn 3 (2 ppm) SO 2 at 19°C and 75 percent relative humidity
for 90 days in the absence of light. Only nylon showed a significant loss in breaking strength, and the loss was small—
less than 5 percent. The investigators concluded that SO 2 itself had a direct deleterious effect on the nylon and
that little or no S02 was converted to sulfuric acid.
The study of Long and Saville 21 followed up Fye’s work. They exposed acrylic, modacrylic, nylon, and
polyester fabric specimens to the conditions previously described. As Table 2-4 shows, acrylic, nylon, and polyester
fibers decreased slightly in strength, while the strength of the modacrylic specimens increased a small amount.
Therefore, none of the fibers showed pronounced damage despite the severity of the exposure conditions. The
absence of artificial sunlight may have been a factor.
In recently completed laboratory research, Zeronian et a!. 28 simultaneously exposed modacrylic (Dynel),
nylon 66, and polyester (Dacron) fabrics to artificial sunlight (xenon arc) and charcoal-filtered clean air contami-
nated with 486 pg/nr’ (0.2 ppm) SO 2 . The fabric samples were also automatically sprayed with water for 18
minutes every 2 hours during exposure. During the “light only” part of the cycle, the exposure temperature was
48°C and the relative humidity 39 percent. To separate the damage that SO 2 may cause from the detrimental
effects of artificial sunlight, fabric samples were also exposed to the same controlled environmental conditions,
except that the clean air was not contaminated with SO 2 . Loss in fiber strength was the prime measure used to
assess degradation.
After exposure for 7 days to these controlled environments, Zeronian et al. found that SO 2 did not affect
the modacrylic and polyester fabrics, but did significantly accelerate the degradation of nylon. The nylon fabrics
exposed to SO 2 lost 80 percent of their strength, while the fabrics exposed to uncontaminated air lost 40 percent
of their strength. The exposure results also show that SO 2 can degrade nylon in the absence of particulate matter.
By means of other physical and chemical tests, the investigators further concluded that, under these exposure
conditions, degradation was not caused by acid hydrolysis resulting from the conversion of SO 2 to sulfuric
acid. Sufficient chemical evidence, however, was not collected in this study to permit elucidation of the
mechanism of the photodegradation of nylon in the presence of SO 2 . The investigators pointed out that the
nylon used in this study was a commercial grade containing a delustrant. Since delustrants accelerate the
photooxidation of nylon, further research is needed to establish whether delustrants influence reactions between
SO 2 and nylon.
Zeronian 29 also examined the surfaces of exposed nylon fibers under a scanning electron microscope. He
observed that the surfaces of fibers exposed for 7 days to light (xenon arc) and clean air, plus intermittent water
spraying, developed a small number of scattered minute pits. Under similar exposure conditions but with the clean
air contaminated with 486 pg/ni 3 (0.2 ppm) SO 2 , however, the nylon surfaces developed numerous large cavities;
on some fibers, finely etched lines were also present. A similar appearance was also found on fibers exposed for
14 days to light and clean air (no SO 2 ) with intermittent water spraying, although loss in tensile strength (70 per-
cent) was less than the loss (80 percent) found when SO 2 was present. Apparently, SO 2 accelerates degradation
under these exposure conditions, but does not alter the manner in which degradation takes place. Zeronian also
observed that cavities and pits seem to develop only when intermittent water spraying is a part of the exposure
conditions. The surfaces of nylon fibers remained smooth when the samples were exposed for 7 days to light and
air (49°C and 38 percent relative humidity) contaminated with 486 pg/rn 3 (0.2 ppm) SO 2 , but without periodic
water spraying. Loss in strength was 50 percent under these conditions. Additional research is necessary to assess
the significance of the surface imperfections observed in these experiments.
16 EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
-------
NITROGEN OXIDES
Nitrogen oxides (NO ) are prime components of photochemical smog. Among the nitrogen oxides, nitric
oxide (NO) and nitrogen dioxide (NO 2 ) are the most important as pollutants. Nitric oxide is the main product
formed during high-temperature combustion processes when atmospheric oxygen and nitrogen combine. Although
some NO 2 is also produced during these processes, most of the NO 2 found in ambient air is formed by the oxidation
of NO. The presence of sunlight and hydrocarbons in the atmosphere accelerates this oxidation reaction enormously.
The main sources of NO, emissions to the atmosphere are automobiles and power plants.
Effects on Natural Fibers
Researchers have not studied the direct effects of NO on cellulosic fibers, but Morris et al. 3 conducted a
field investigation in Berkeley, California, in which they attributed the observed fiber damage to ambient levels of
NOR. They exposed samples of combed cotton yarn at a 45-degree angle in cabinets facing south. Polyvinyl fluoride
film, rather than glass, was used to cover the cabinets in order to allow a greater amo mt of sunlight toenter. One
cabinet was set up as a control unit in which entering air was filtered through carbon canisters; ambient air was
circulated through the other cabinet. (The investigators did not note the rate of air change.) in each cabinet some
samples were exposed directly to daylight, while like samples were shaded. Samples were exposed for three separate
28-day periods (December through February), as well as for consecutive combinations of these three periods
able 2-5). During exposure, air pollution and weather measurements were made as shown in Table 2-6.
At least 20 yarn specimens were evaluated for each exposure period. The investigators assessed deterioration
by measuring loss in breaking strength. Table 2-5 shows, for the various exposure periods, mean values for the
percentage loss in breaking strength for unshaded samples exposed to filtered and unfiltered ambient air. An analysis
of variance of these mean loss values revealed that unfiltered air deteriorates cotton yarn to a significantly greater
extent than filtered air. No difference was observed, however, in the effects of filtered and unfiltered air on the
shaded samples. Although textile investigators have been aware of the pronounced deteriorating action of direct
sunlight, the results of this study emphasize the importance of sunlight in stimulating reactions between some air
pollutants and materials. It is noteworthy that the smallest difference in breaking-strength losses between filtered
and unfiltered air occurred during February, which is the period having the most rain (which cleans the air), the
lowest levels of NOR, and the lowest total hours of sunshine. Although they found it impossible to determine the
respomible pollutant in this study, the investigators proposed that nitrogen oxides, either directly or indirectly, were
instrumental in causing damage. Sulfur dioxide was not measured because levels were known to be low.
The investigators did not mention the fact that the filter material, activated carbon, adsorbs NO 2 effectively
but adsorbs NO poorly. Levels of NO in the filtered air cabinet could, conceivably, have contributed to the decrease
in breaking strength. If this were the case, cotton specimens exposed to clean air would show a smaller loss in break-
ing strength, and the relative pollution effect would increase.
Effects on Synthetic Fibers and Blends
Several investigators, working with synthetic fibers, have found that under laboratory conditions nitrogen
oxides are capable of causing damage. They reason, therefore, that these pollutants are potential threats under
ambient conditions. Damage reports from the field, however, have been few, and only one incident has been
documented.
In March 1964, an episode of runs in nylon stockings worn by women occurred in the vicinity of a demolition
project in downtown New York City. 31 Investigators identthed the agent causing the damage as NO 2 gas released
during dynamite blasting operations. Local weather conditions at that time were unfavorable in that a temperature
inversion existed along with wind stagnation and high humidity. The investigators proposed that the combination
of these conditions in the presence of abnormally high levels of released NO 2 and dust had produced nitric acid
aerosols that damaged the nylon stockings.
Effects of Air Pollutants on Textile Fibers 17
-------
Table 2-5. BREAKING STRENGTH OF COTTON YARN SAMPLES
EXPOSED TO AIR AND SUNLIGHT IN BERKELEY, CALIFORNIA
Exposure
Breaking strength lost, %
Number of
days
Period
Filtered air
Unfiltered air
28
28
28
56
56
84
Dec.
Jan.
Feb.
Dec. - Jan.
Jan. - Feb.
Dec. - Feb.
11
15
15
20
19
26
15
18
16
24
29
32
Table 2-6. AIR POLLUTANT LEVELSa AND WEATHER MEASUREMENTS
Exposure
period
Total oxidant
Nitric oxide
Nitrogen
dioxide
Temp.,
OC
Total
sunshine,
% days
Rain,
in.
ppm
ig/m 3
ppm
ug/m 3
—
ppm
—
pg/rn 3
Dec.
Jan.
Feb.
0.03
0.03
0.03
bO
60
60
0.19
0.23
0.07
230
280
90
0.08
0.08
0.05
150
150
90
10
10
10
100
100
72
0.5
6
10
aFor clock hour with highest average value.
Travnicek gathered information on incidents involving air pollution damage to nylon stockings and, noting
the New York City episode, offered the opinion that “the corrosive effect of nitrogen oxides is rather high not
only for nylons but for practically all other fiber-forming polymers because it combines acid corrosion and
oxidation.”
Because nitrogen oxides are major components of auto exhaust, the laboratory research that Travnicek 25
carried out may be significant. He exposed samples of synthetic fibers (only nylon is identified) for 50 hours to a
continuous flow of undiluted auto exhaust in a controlled-environment chamber illuminated by artificial sunlight,.
Travnicek found that under these exposure conditions, the physical properties of the fibers changed, and that the
changes were caused by the interplay of two reactions: cross-linking, probably the result of aldehydes; and
18 EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
-------
depolytnerization. caused largely by light. Furthermore, he observed that, to a certain degree. some light stabilizers
and dyes. because of preferential reactions with oxidizing agents. protected the fIbers from degradation. Protection
is most evident when NO and sunlight transform components of exhaust gases into oxidtztng agents. When fibers
were exposed to dilute exhaust gases. which simulated summertime conditions on traffic-congested streets. Travnicek
found that the diluted gases became a potential menace to these fibers only if given sufficient time and light to
produce oxidizing substances. He did not define “sufficient time and light.” According to Travnicek. therefore.
NO may attack and damage fibers through the formation of nitric acid droplets. by direct oxidation, and by con-
version of other exhaust components into harmful oxidizing agents. Unfortunately. Travnicek discusses generalities
and does not present a detailed account of his methodology and results.
Nitrogen oxides may pose a problem for Spandex. a synthetic elastorneric fiber, On exposure to a standard
laboratory test rocedure in which levels of N02 were about 2500 pg/rn 3 (1 .5 ppm). Spandex developed a yellowish
discoloration. 3 - This result is not a case of dye fading since the exposed material contained no dyes or color pie-
rnents rather, the NO react directly with the polymer. Although the laboratory test exposure levels are sonicwhat
higher than measured levels in ambient air, problems ma develop under ambient conditions. So far, however, few
complaints from the field have been reghtered.
Citing recent technology on the dyeing of DuPont nylon yarns. Trommer 33 states that nylon polymers arc
subject to oxidation by NO and other oxidants. and may themselves serve as reducing agents. If oxidation occurs.
nylon fibers then have less affinity for acid dyes. Natural (undyed) continuous-filament styling yarns. which have
a high capacity for acid dyes. are especially sensitive to oxidation reactions. Trommer cautions that these nylon
yarns should not be exposed for prolonged periods to factory environments in which fork trucks emit exhaust
fumes.
In laboratory research that Zeronian et a!. 28 completed in 1971. fabric samples of modacrylic (Dynel).
acrylic (Orion), nylon 66, and polyester (Dacron) were simultaneously exposed to artificial light (xenon arc) and
charcoal-filtered clean air contaminated with 350 p ’m 3 (0.2 ppm) NO at 48°C and 39 percent relative humidity.
During exposure. the fabric samples were sprayed with water for IS ininutes every 2 hours. Damage by NO was
measured by comparison with fabrics exposed to the same environmental conditions but without NO,. When they
exposed the fabrics to these controlled conditions for 7 days. Zeronian et al. found that NO 2 did not affect the
modacrylic fabrics, but appeared to affect the other fabrics slightly. The evidence for damage to nylon appeared to
be the strongest, although the investigators emphasize that the results for all fabrics were not clear and that more
research is needed.
OZONE
Ozone occurs naturally in the atmosphere however, undesirable concentrations of ozone often occur as a
result of complex photochemical reactions between NO and hydrocarbons. Thus, ozone is a principal component
of photochemical smog and is primarily an indirect product of automobile emissions.
Effects on Natrual Fibers
Because cellulose fibers are vulnerable to oxidation, ambient levels of atmospheric ozone, a powerful oxidizing
agent, are a potential cause of degradation. With this in mind. Bogaty et al. 34 conducted laboratory experiments
to study the possible role of ozone in the deterioration of cotton products. They exposed samples of duck and print
cloth to air containing between 40 arid I 20 pg/rn 3 (0.02 and 0.06 ppm) ozone at room temperature and in the
absence of light. Samples were exposed both dry and wet; the moisture content of the wet samples was never less
than 50 percent.
After exposure for 50 days, fluidity values increased for the cotton samples that were moist during exposure.
but did not appreciably change for the samples that remained dry during exposure. Fluidity values for control
samples that were kept moist but not exposed to ozone showed little change. These results indicated that ozone
Effects of Air pollutants on Textile Fibers I
-------
caused virtually all the degradation. In addition to changes in fluidity, the moist samples showed a 20 percent loss
in tensile strength after exposure to ozone. Similar fabrics were also exposed to higher levels of ozone, resulting
in a greater increase in the degradation (fluidity) of the moist samples. The overall study showed that low levels
of ozone degrade cotton fabrics if the fabrics are sufficiently moist. The mechanism of ozone attack appears
primarily to be solubilization in water, since at room temperature ozone is considerably more soluble in water than
it is in air.
The investigators estimated that the laboratory exposure conditions (50 days, high moisture, and ozone) arc
equivalent to 500 days of exposure under field conditions. They concluded that ambient levels of ozone, while
capable of damaging moist cotton fabrics, produces deterioration that is slight in comparison with that from other
elements of weathering such as light, heat, alternate wetting and drying, and micro-organisms.
Morris 35 also studied the effect of ozone on cotton. Samples of special print cloth were exposed in the
absence of light to 995 jig/rn 3 (0.5 ppm) ozone for 50 days in a chamber maintained at 21°C and 72 percent relative
humidity. No appreciable effect on breaking strength or fluidity was found. Apparently the moisture content of
the cotton (9 percent) was not high enough to produce the degradation that Bogaty measured on wet cotton
samples, even though the concentration of ozone was considerably higher (about 10 times).
In a recent laboratory study. Kerr et aL 36 examined the effect of periodic washing on the tendering of cotton
fabrics exposed to ozone. They exposed samples of print cloth, dyed with C. I. Vat Blue 29, in a chamber to a con-
tinuous supply of clean air contaminated with ozone. The concentration of ozone averaged 1470 pg/rn 3 (0.75 ppm),
and samples were exposed at room temperature in the absence of light. The investigators did not measure relative
humidity. although they attempted to increase the humidity by placing a pan of water on the chamber floor. At
3-day intervals the cotton samples were removed from the chamber. Half of them were machine-washed and the
other half were soaked in water for 1 minute. All samples were passed through a hand wringer to remove
excess water before being returned to the chamber for further exposure. Control samples were kept in a light-
tight box maintained at 21°C and 65 percent relative humidity and were given the same washing and soaking
treatment.
After the samples were exposed for 60 days, which included 20 washing or soaking treatments, the change in
strength for the control fabrics was measured and found to be insignificant. By comparison the fabrics exposed to
ozone changed significantly; the loss in strength for the washed fabrics was 18 percent and for the soaked fabrics
9 percent. The investigators attributed these losses to ozone.
Since Morris 35 found no degradation under exposure conditions similar to those used by Kerr, the washing
and soaking treatment would appear to affect in some way the sensitivity of the fabrics to ozone. Nevertheless, if
one attempts to equate Kerr’s fIndings with “real world” conditions, the degradation appears minimal in view of the
fact that average levels of ozone under field conditions are less than 10 percent of the levels used in the laboratory
exposure.
Effects on Synthetic Fibers and Blends
Despite the strong oxidizing power of atmospheric ozone, little research has been carried out on the effects
of this pollutant on synthetic fibers. Peters and Saville, 37 however, did study the combined damaging effects of
high levels of ozone and ultraviolet light on the breaking strength of white curtain marquisettes made of nylon,
polyester, cotton, acetate, and fiber glass. They exposed samples of these fabrics in a chamber under conditions
that were not tightly controlled. Ozone generators located inside the chamber were adjusted to produce a level of
ozone sufficient to fade an ozone-sensitive acetate test ribbon during a 9-day exposure period an amount equiva-
lent to Step 2 on the International Geometric Gray Scale. The investigators made no estimates of the levels of
ozone produced under these conditions except to say that they were high. During exposure, the tempera-
ture averaged 31°C and the relative humidity averaged 68 percent. The intensity of the ultraviolet light was
not measured.
20 EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
-------
The investigators found that, after exposure under these conditions for 45 days, the loss in breaking strength
fornylon averaged 64 percent, for polyester 18 percent, for acetate 15 percent, for cotton 12 percent, and for fiber
glass 7 percent. Because no control fabrics were exposed under similar conditions but in the absence of ozone, it is
impossible to establish the damage contribution by ozone, if any. This factor is especially significant since ultra-
violet light is considered the prime environmental source of fiber degradation.
In more sophisticated laboratory studies, Zeronian et al. 28 simultaneously exposed modacrylic (Dynel),
acrylic (Orion), nylon 66, and polyester (Dacron) fabrics to artificial sunlight (xenon arc) and charcoal-filtered
clean air contaminated with 365 pg/rn 3 (0.2 ppm) ozone at 48°C and 39 percent relative humidity. During ex-
posure, the fabric samples were sprayed with water for 18 minutes every 2 hours. Ozone damage was measured by
comparison with fabrics exposed to the same environmental conditions but without ozone. After exposure for 7
days, Zeronian et al. found that ozone did not affect the modacrylic and polyester fibers, but seemed to affect the
acrylic and nylon fibers slightly.
REFERENCES FOR CHAPTER 2
1. Dorset, B. C. M. Soiling of Textile Fabrics and Garments. Text. Mfr. 94 (1122): 248-254, June 1968.
2. Wilkie, J. B. Laundry “Winter Damage.” J. Res. Nat. Bur. Stand. 6:593-602, April 1931.
3. The Tendering of Fabrics by Smoky Air. Shirley Institute Bulletin. 28:70-71, 1955.
4. Rees, W. H. Atmospheric Pollution and the Soiling of Textile Materials. Brit. 1. AppI. Phys, 9:301-305,
August 1958.
5. Morris, M. A. and B. Wilsey. The Effect of Soil on the Photocherrucal Degradation of Cotton. Text. Res. J.
29:971 -974, December 1959.
6. Morris, M. A. andM. A. Young. The Exposure of Soiled Cotton to Sunlight: Degradation and Color Changes.
Text. Res. J. 35:178-180, February 1965.
7. Morris, M. A., B. W. Mitchell, and T. Aas-Wang. The Effect of an Airborne Soil on the Photochemical Degra-
dation of Wool. Text. Res. J. 32:723-727, September 1962.
8. Johnson, A. E. Window Fabric Damage—Some Causes and Cures. Curtain & Drapery Dept. Magazine. 1-8,
June 1960.
9. Holmes, F. H. Soiling of Man-Made Fibers. Shirley Institute Bulletin. 39:102-105, 1966.
10. Morris, M. A. and B. W. Mitchell. The Effect of an Airborne Soil on the Photodegradation of Nylon. Text.
Res. J. 31:488, May 1961.
11. Petrie, 1. C. Smoke—and the Curtains. Smokeless Air. 18:62-64, Summer 1948.
12. Race, E. The Degradation of Cotton during Atmospheric Exposure, Particularly in Industrial Regions. J. Soc.
Dyers Colour. 65:56-63, February 1949.
13. Pomroy, E. R. and H. T. Stevens. The Effects of Weather on Drapery Lining Fabrics in Two Geographic
Regions. J. Home Econ. 56:607-6 14, October 1964.
14. Kanawha Valley Air Pollution Study. U. S. DHEW, PHS, Environmental Health Service. Washington, D. C.
March 1970. p. 4-1—4-139.
15. Little, A. H. The Effect of Light on Textiles. J. Soc. Dyers Colour. 80:527-534, October 1964.
16. Little, A. H. and H. L. Parsons. The Weathering of Cotton, Nylon, and Terylene Fabrics in the United Kingdom.
J. Test. Inst. 58:449-462, October 1967.
17. Clibbens, D. A. The Weathering of Cotton, Nylon, and Terylene Fabrics in the United Kingdom. Text. Inst.
md. 6:20-21, January 1968.
Effects of Air Pollutants on Textile Fibers 21
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18. Biysson, R. J., B. J. Trask, J. B. Upham, and S. G. Booras. The Effects of Air Pollution on Exposed Cotton
Fabrics. J. Air Poll. Contr. Assoc. 17:294-298, May 1967.
19. Brysson, R. J., B. J. Trask, and A. S. Cooper, Jr. The Durability of Cotton Textiles: The Effects of Exposure
in Contaminated Atmospheres. Amer. Dyest. Rep. 57:512-517, July 1968.
20. Fye, Cecelia, K. Flaskerud, and D. Saville. Effect of an SO 2 Atmosphere on the Breaking Strength of Fabrics
of Different Fiber Content. Amer. Dyest. Rep. 58: 16-19, July 1969.
21. Long, S. H. and D. Savifie. Exposure of Fabrics to a Polluted Atmosphere: Apparatus to Produce High
Humidity. Amer. Dyest. Rep. 60:48,50, 53, October 1971.
22. Zeroman, S. H. Reaction of Cellulosic Fabrics to Air Contaminated with Sulfur Dioxide. Text. Res. J.
40:695-698, August 1970.
23. Unusual Failures of Stockings in Service. Tech. News Bull., Nati. Bur. Standards. 33, March 22, 1941
24. Personal communication with H. 1. Salmon, E. 1. DuPont deNemours and Company. 1964.
25. Travnicek, Z. Effects of Air Pollution on Textiles, Especially Synthetic Fibers. In: Proceedings, Intern. Clean
Air Congr. London, England, October 1966. p. 224-226.
26. Travnicck, Z. Damage to Nylon Stockings by Atmospheric Contamination. Wirkerei-und Strickerei Tech.
17:345-354, July 1967.
27. Acid. The New Yorker. 28(6):25.26, March 29, 1952.
28. Zeronian, S. H., K. W. Alger, and S. T. Omaye. Reaction of Fabrics Made from Synthetic Fibers to Air Con-
taminated with Nitrogen Dioxide, Ozone, or Sulfur Dioxide. In: Proceedings, Second Intern. Clean Air
Congr. Englund, H. M. and W. T. Beery (eds.). New York, Academic Press, 1971. p.468-476.
29. Zeronian, S. H. The Effect of Ught and Air Contaminated with Sulfur Dioxide on the Surface of Nylon 66
Fibers. Text Res.J. 41:184-185, February 1971.
30. Morris, M. A., M. A. Young, and 1. A. Molvig. The Effect of Air Pollutants on Cotton. Text. Res. J. 34:563-
564, June 1964.
31. City Finds Nylon Culprit: Blasting Gas. The New York Times, March Il, 1964.
32. Salvin, V. S. Effect of Atmospheric Contaminants on Fabrics—Dyed and Undyed. Amer. Soc. Qual. Contr..
Textiles and Needle Trades Div., Text. Qual. Contr. Papers. 16:56-64, 1969.
33. Trommer, K. H. Recent Technology in the Dyeing of DuPont Nylon Styling Yarns. Can. Text. J. 85:31-34,
August 1968.
34. Bogaty, H., K. S. Campbell, and W. 1). Appel. The Oxidation of Cellulose by Ozone in Small Concentrations.
Text. Res. J. 22:81-83, Februasy 1952.
35. Moms, M. A. Effect of Weathering on Cotton Fabrics. California Agricultural Experimental Station, Univ.
of Calif., Davis, Calif. Bulletin 828. June 1966. 29 p.
36. Kerr, N., M. A. Morris, and S. H. Zeroman. The Effect of Ozone and Laundering on a Vat-Dyed Cotton Fabric.
Amer. Dyest. Rep. 58:34-36, January 1969.
37. Peters, J. S. and D. Saville. Fabric Deterioration: A Test Chamber for Exposure of Fabrics to a Contaminated
Atmosphere. Amer. Dyest. Rep. 56:340-342, May 1967.
22 EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
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CHAPTER 3
EFFECTS OF AIR POLLUTANTS ON
TEXTILE DYES AND ADDITIVES
Although sunlight is the major cause of color defects in dyed textile fabrics, air pollutants, to the dismay of
the textile industry, are also important factors in causing color defects. Just as dyes vary in their sensitivity to sun-
light, so do they vary in their sensitivity to individual pollutants. With sunlight, the more sensitive dye molecules
become activated and unstable as they absorb actinic energy. This instability is short-lived, however, and the dye
molecules usually break down, normally by oxidation but sometimes by reduction, resulting in a change or loss in
color. Pollutants react directly with sensitive dyes to produce different compounds and colors. In many cases, en-
vironmental factors such as relative humidity and sunlight play major roles by accelerating the rates of chemical
reaction. Closely related to color change problems induced by air pollution are the effects of pollutants on textile
additives, which are widely used to enhance certain properties of fabrics and dyes. Additives include light stabi-
lizers, permanent-press resins, optical brighteners, antistatic and soil-release finishers, softeners, and various inhibi-
tors.
SULFUR OXIDES
Potential Problem
Although the textile industry has reported many incidents of dyed fabrics developing color defects, none have
been attributed to ambient levels of atmospheric SO 2 . However, because SO, and solutions of its reaction produce
with water—sulfurous acid—are active reducing agents and are used to bleach wool and silk, dye chemists have
recognized for some time that atmospheric SO 2 could be potentially troublesome. They are also aware that portions
of dyed fabrics have faded when placed in direct contact with paper or other fiber products manufactured from
sulfite pulp; frequently these paper products contain residual SO 2 .’ In addition, many dyes are basic compounds,
and some, especially those developed and used many years ago, are sensitive to acid-base changes. Color changes
resulting from such sensitivity are called acid fading. The original color shade of dyes susceptible to acid fading can
be easily restored by the application of ammonia or other mild alkali. 2 Although airborne acid aerosols derived
from SO 2 (sulfurous and sulfuric acids) could cause acid fading, such fading is no longer a common problem be-
cause present-day dyehouse processing operations include exposure of dyed fabrics to dilute mineral acids; as a
consequence, acid-susceptible dyes cannot be used.
Early Laboratory Investigations
The lack of evidence against fading by atmospheric SO 2 has not lulled researchers into a “do-nothing”
attitude. During the late 1920’s and the 1930’s, several laboratory studies were conducted to assess the effects of
S0 2 -contaniinated air on dyes. In most exposures, SO 2 was chemically generated and concentrations were not
measured. Scientists generally assumed, however, that concentrations were considerably higher than those that
normally exist in industrial environments.
Cunliffe 3 subjected a number of dyes on cotton, viscose rayon, linen, silk, and wool to S0 2 -coritaminated
air, both in the presence and absence of artificial light. He found that in the presence of light S02 decreased the
fading rate of sulfur dyes on cotton, rayon, and linen, and of azo dyes on cotton. Sulfur dioxide either increased
23
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or decreased the fading rates of the remaining dyes on the cellulosic fabrics and of all dyes on wool and silk. For a
number of dyes, changes in hue also were noted in addition to fading. In the exposures conducted in darkness,
SO 2 affected the majority of the dyes on all fibers; dyes on cotton showed the greatest variety of change. Since
SO 2 concentrations were not stated, however, it is not possible to assess completely the significance of these results.
Prior to the late 1920’s, dye chemists thought that if SO 2 caused color defects, it would be either by bleach-
ing or by an acid-base reaction. The research of King 1 ’ 4 and Goodall 5 brought to light another mechanism by
which SO 2 can cause dyes to fade. They showed that, because fabrics are usually slightly alkaline as a result of resi-
dues remaining from previous processing and laundering operations, SO 2 , in the presence of moisture, can react
with the alkali to form bisulfites and alkali sulfites. These sulfites can cause color defects by reacting with sensitive
dyes to form addition compounds or by completely reducing the dyes. The addition reaction is more common and
certain azo dyes on wool are especially sensitive. The researchers found that optimum conditions for the formation
of azo-sulfite addition compounds occur when the pH is slightly acid (6.8 to 6.9) and the concentration of alkali
is from 1.25 to 1.4 times that of SO 2 . Conceivably, these optimum conditions could be met by ambient levels of
S02-contamrnated air. The reduction reaction is comparatively slow and optimum conditions vary with each dye.
Although sulfite-induced color defects in dyed fabrics are easily produced in the laboratory, none have been
observed in service.
Subsequent laboratory studies revealed that certain dyed fabrics were reasonably resistant to color changes
when exposed to S0 2 -contaminated air. Jones 6 subjected dyed cotton fabrics (nine vat dyes) and viscose rayon
fabrics (nine vat dyes, four direct dyes, and one sulfur dye) to dry air containing about 3000 ppm SO 2 and to moist
air (humidity not given) containing about 3000 ppm SO 2 . Both exposures, each lasting 41 days, were conducted
at room temperature and under glass, to allow natural sunlight to fall on the fabric samples. No dyed fabrics faded
when exposed to the dry-air-conditions. Under the moist-air conditions, one vat-dyed cotton fabric showed
obvious fading and two others showed slight fading; no rayon fabrics faded.
Rowe and Chamberlain 7 found that gaseous SO 2 had little effect when passed into aqueous suspensions of
basic dyes (anthraquinonid family) for acetate rayon. When SO 2 and NO were simultaneously passed into aqueous
suspensions of these dyes, SO 2 appeared to modify the pronounced fading action of NO(. On the basis of these
severe tests, the investigators concluded that ambient levels of SO 2 , though still capable of causing acid fading,
should not directly fade these dyes.
Laboratory investigations carried out in the late 1940’s likewise showed a negative effect for SO,-contami-
nated air. 8 No visible color changes developed on several dyed viscose and acetate rayon fabrics when they were
exposed for 2 hours to air containing about 320 ppm SO 2 at 65°C and 50 percent relative humidity. Neither did
exposures conducted at lower temperatures and humidities produce color defects.
AATCC Laboratory and Field Exposures
During the 1950’s, investigators conducting lightfastness tests (measuring resistance to fading by sunlight)
found that significant differences in lightfastness occurred among some dyed fabrics when they were exposed out-
doors to equivalent amounts of sunlight but at different localities. The investigators reasoned that one of the
variables responsible for this result was contaminated air. To explore this variable in greater detail, the American
Association of Textile Chemists and Colorists (AATCC) set up a committee to carry out laboratory research and
field studies.
Although the ensuing laboratory research 9 did not include an investigation of the direct effects of SO 2 , it did
include a study of the effects of dilute sulfuric acid. The committee selected 28 dyed fabrics consisting of cellulosic
(cotton and viscose rayon), nylon, and wool fibers, all dyed with conventional dyes. Each fabric was treated with
a weak solution of sulfuric acid (1 gram per liter) at 40°C for 20 minutes followed by a water rinse at 30°C for 5
minutes. After this treatment, the fabrics were inspected for color change. They were then exposed in a Fade-
Ometer for up to 40 hours to evaluate lightfastness. The acid treatment produced no color defects on the dyed
24 EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
-------
nylon and wool fabrics, but several direct dyes on cellulosic fabrics developed moderate acid-base color changes.
More importantly, however, these direct-dyed celiulosic fabrics that had been acid-treated suffered appreciable re-
duction in lightfastness. The AATCC concluded that, during sunlight testing in various geographic locations, the
action of absorbed acid pollutants on dyed cellulosic fabrics may contribute to observed differences in lightfastness.
Subsequently, the AATCC Committee conducted service exposure trials in urban and rural areas. 12 Fifty-
two dyed samples were exposed for 90 days (October-December 1961) at sites in Phoenix, Arizona; Sarasota,
Florida; Los Angeles, California; and Chicago, Illinois. Relative levels of atmospheric contaminants were reason-
ably well-known at the sites chosen. The dyed samples covered a range of fibers: cellulosics, acetate rayon, wool,
nylon, acrylic, and polyester. The investigators selected dyes that were in common use on each fiber. The fabric
samples were mounted inside exposure cabinets designed to allow free interchange of outside air but to exclude
light.
Results showed that the atmosphere of Chicago produced a number of fading effects not observed at the
other sites. Direct dyes and some reactive dyes on cellulosic fibers and acid dyes on wool and nylon developed
pronounced color defects. Because high levels of SO 2 were frequently observed in Chicago, SO 2 or its acid
derivatives were suggested as important factors. Some researchers suspected that the color defects observed on the
cellulosic fabrics were produced by ambient levels of NOR, which were also reasonably high in Chicago. The fading
reaction of NO is markedly accelerated under acid conditions.
Recent Investigations
The service exposure trials were followed up by a more comprehensive field study conducted by air pollution
researchers with the Environmental Protection Agency in cooperation with the AATCC. 13 The investigators
selected 67 dye-fabric combinations for testing; the fibers from which the fabrics were woven included the cellu-
losics (cotton and viscose rayon), acetate rayon, wool, nylon, polyester, and acrylic. The dyes were mainly those
commonly used on these fibers and represented various degrees of known susceptibility to air pollution fading.
Fabric samples were exposed in light4i ht cabinets similar to those used in the service trials. Individual cabinets
were set up at 11 nationwide exposure s t s: Los Angeles, California; Tacoma, Washington; Chicago, Illinois; Wash-
ington, D.C., and at corresponding n.gal control sites for each of these cities; additional single sites were located in
Cincinnati, Ohio; Phoenix, Arizona; a* l Sarasota, Florida. These sites represented a cross section of various types
of pollution and climates. Air pollutants were continuously measured near the urban sites in Chicago, Cincinnati,
Los Angeles, and Washington. The study, conducted over a 2-year period, consisted of eight consecutive seasonal
exposures, lasting 3 months each and commencing with the spring season (March-May 1966). Using a precision
photoelectric colorimetet to measure color before and after exposure, the researchers calculated color changes for
all dyed fabric samples at all sites for all seasonal exposures.
In an effort to identify factors causing fading in this study, the investigators statistically analyzed color
change data, along with air pollution and weather measurements. Of the 67 fabrics exposed, 24 either did not fade
or faded only a trace, and therefore were eliminated from statistical consideration; the remaining 43 fabrics faded
in appreciable amounts. Most of these fabrics faded significantly more at urban sites than at corresponding rural
sites, and the amount of fading varied between metropolitan areas and among seasons. Air pollution was assumed
to account for most of the environmental differences between urban and rural sites.
Of the pollutants measured in this study, SO 2 , NO 2 , and ozone (03) seemed, on further analysis, to be most
responsible for the fading of the fabrics. Temperature and humidity appear to have little influence on fading when
dyed fabrics are exposed in essentially pollution-free environments. In polluted environments, however, high
temperature and humidity may accelerate fading. Sulfur dioxide was a significant variable in the fading of 23 of
the dyed fabrics. Furthermore, these fabrics faded only in Chicago, when SO 2 levels were high (fall and winter
seasons). The apparent dominance of SO 2 , however, should be qualified. High levels of SO 2 occurred only in
Chicago; therefore, at no other exposure site could the researchers verify the fading measured in Chicago. In addi-
tion, despite measures taken to niiiw ize it during exposure, soiling occurred and was particularly noticeable in
Chicago. As a result, soiling confounded the statistical analyses.
Effects of Air Pollutants on Textile Dyes and Additives 25
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Also of interest in this study is the fact that 45 of the 67 fabncs exposed experienced maximum fading in
Oiicago during at least one season. The most severe cases were the acid-dyed woolen fabrics. Many of the fabrics,
however, showed considerably less fading than that observed on the woolens. Some of the fabrics that faded in
Qiicago are even considered to be generally resistant to fading by all air pollutants. Here again, soiling may have
contributed to observed changes in color, especially for the pastel shades.
Also as part of this investigation, these same dye-fabric combinations were exposed, in the absence of light,
to various combinations of dilute auto exhaust and S0 2 .14 Each fabric was exposed to clean air for 6 days, with
the pollutants added for 9 hours each day. Auto exhaust alone produced no fading, nor did clean air plus 2620
jig/rn 3 (1 ppm) SO 2 . Irradiated auto exhaust, however, caused significant fading in some dyes; and irradiated
exhaust plus 2620 jig/rn 3 (1 ppm) SO 2 produced fading in additional dyes, as well as more pronounced fading in
those dyed that faded without SO 2 . These results ifiustrate the positive synergistic effect of SO 2 and auto exhaust,
emphasizing that in many cases damage is a function of pollutants working together rather than by themselves.
Belom t5 conducted laboratory studies that were designed to assess directly the effects of individual pollut-
ants on dyed fabrics. He exposed 20 dye-fabric combinations for 12 consecutive weeks in the absence of light to
individually controlled environments consisting of charcoal-filtered clean air (controls) and clean air contaminated
with single pollutants. The pollutants were SO 2 , NO, NO 2 , and ozone (03). Controlled exposure conditions in-
cluded clean air and two pollution levels, 260 jig/m 3 (0.1 ppm) SO 2 and 2600 jig/rn 3 (1.0 ppm) SO 2 , all under
four combinations of temperature and relative humidity (RH): 32°C, 50 percent RH; 32°C, 90 percent Ri-I; 13°C,
50 percent RH; and 13°C, 90 percent RH. The 20 fabrics selected were a cross section of those that showed the
greatest tendency to fade during the field study 13 previously described, together with several nonfaders that served
as controls.
Exposure results showed that SO 2 caused some cotton, nylon, and wool fabrics to fade. For the cotton and
nylon fabrics, however, the fading effect of other pollutants was much stronger than that of SO 2 . This was not the
case for the wool fabrics; SO 2 was the only pollutant to cause visible fading. Relative humidity was a significant
factor in accelerating the fading action of SO 2 on these wool fabrics, especially during exposure to the higher SO 2
concentration. The magnitude of fading measured on the wool fabrics after exposure to the most severe SO 2 con-
trolled environments, however, was considerably less than the magnitude of fading that many of the other fabrics
developed during exposure to NO 2 or 03.
Despite the fact that service complaints concerning color defects on textile fabrics have not been attributed
to S0 2 -contaminated air (although suspected in some cases), researchers believe that the potential is still real.
Presently, both the AATCC and European groups are developing test procedures to assess colorfastness to S0 2 -con-
taniinated air.
NITROGEN OXIDES
Discovery of “Gas Fading”
The fading effects of NO have been a problem for the textile industry for many decades. Evidence first ap-
peared in Germany just prior to World War I when a dye manufacturer investigated some unusual cases of dye fad-
ing on stored wool goods.’ 6 Fading was most noticeable on the edges of the goods, and the primary cause was traced
to NO in the air. Open electric-arc lamps and incandescent gas mantles were major sources of these pollutants,
which were produced by high-temperature fixation of nitrogen in the air. The investigators found that all the
susceptible dyes contained free or substituted amino groups, which they suggested might become either diazotized
or mtrosated by the NOR.
During and following World War I, increased replacement of older forms of lighting with electric filament
lamps led to a neral decline of the wool-fading problem. In the mid-1920’s, however, researchers developed and
introduced a new fiber, cellulose acetate rayon, and, since traditional dyes were of little use on the new material,
chemists soon developed an entirely new line of dyestuff called disperse dyes. These dyes are slightly soluble in
26 EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
-------
water and color acetate fibers by a mechanism of solid solution. Many are derived from anthraquinone and there-
fore contain amino groups, the same groups the Germans had previously found susceptible to NO fading. Anthra-
quinone dyes are basic compounds; basicity is necessary for adequate dyeing affinity.
Shortly after the introduction of disperse-dyed acetate fabrics, a puzzling type of fading began to show up
more and more. Fading occurred mainly on blue and violet shades, with both colors developing a pronounced red-
dening. Because this fading was frequently observed in rooms heated by gas heaters, it was called “gas-fume fading”
or “gas fading,” and was confined to disperse dyes on cellulose acetate rayon.
During the 1930’s acetate fading became a serious problem as an increasing number of fading incidents came
to the attention of the textile industry. These incidents occurred during manufacturing and storage, product dis-
play by retailers, drying and ironing of laundered garments, and storage by consumers. 2 ’ 6 Apparently unaware of
the earlier German work, dye and fiber chemists devoted considerable efforts toward finding a solution. These ef-
forts culminated in 1937 when Rowe and Chamberlain 7 systematically investigated the fundamental chemistry of
dye degradation. They independently reached the same conclusions as the earlier German team—that NO , were
the active agents in combusted gas that caused a number of dyes on acetate fabrics to fade permanently. The in-
vestigators also found that these same dyes, when applied to wool rather than acetate fabrics, showed little fading
on exposure to combusted gas, contrary to the German observations. Rowe and Chamberlain concluded that wool
absorbs NO thus protecting the dyes from attack. In the German research, the woolen goods may have reached
their maximum ability to absorb NOR, so that the NO was then available to react with the sensitive dyes.
By the late 1930’s, gas-sensitive dyes on acetate rayon fabrics covered about one-half the color spectrum. 17
Dyes covering the other half, including most of the yellows, oranges, and reds, consisted largely of azo compounds
and were reasonably resistant. Mod shades, which require several component dyes including the sensitive blues, are
also subject to gas fading.
Standard Test Method
Recognizing the importance of the problem, the AATCC Committee on Colorfastness to Atmospheric Con-
taminants, supplemented by outside research, 8 ’ 822 developed a fading test procedure that the members tenta-
tively adopted in 1941 and formally approved in 1957. It is presently designated as Test Method 23-1972, Color-
fastness to Burnt Gas Fumes. 23 This method calls for suspending test specimens, along with gas-fading control
samples (AATCC Control Sample No. I), in a chamber and exposing them to combustion gases from a gas burner
that hasbeen adjusted so that the chamber temperature does not exceed 60°C. The resulting concentration of NO 2
is about 2.5 milligrams per cubic meter (mg/rn 3 ) (1.5 ppm). Relative humidity is not measured or controlled, but
depends on the moisture content of the air at the time of testing. The control sample, frequently called the gas-
fading control ribbon, is a satin cellulose acetate fabric dyed with 1 percent C. I. Disperse Blue 3, a sensitive
anthraquinone dye. Specimens remain in the chamber until the control sample shows a change in shade (duller and
redder) corresponding to a dyed viscose rayon satin fabric (AATCC Standard of Fading No. 1). This color change
constitutes one cycle and the specimens are said to have had a treatment equivalent to 6 months of actual exposure
to average levels of NOR, representative of NO levels at three separate locations in southern New Jersey. If the
test specimens do not change color appreciably after one exposure cycle, the procedure is repeated (with the use of
a fresh control sample) as many times as necessary to make an evaluation. Dyed fabrics are classified and rated ac-
cording to the number of exposure cycles necessary to produce appreciable changes in shade. This method has be-
come the accepted standard of comparison for all dyes. Experience has shown that consumers generally begin to
complain when fading equivalent to slightly more than two exposure cycles has taken place. 24
Laboratory Investigations
During and since the 1940’s, much research has been carried out in an effort to understand gas fading and to
develop ways of preventing it. Seibert 18 considered auto exhaust gases as a possible source of atmospheric con-
tarnination. He took acetate rayon fabrics that were colored with dyes having a known range in sensitivity to gas
Effects of Air Pollutants on Textile Dyes and Additives 27
-------
fading and exposed them directly to escaping exhaust gases. The fabrics with known sensitive dyes showed obvious
color changes. He assumed the fading was caused by NO in the exhaust gases.
Ray et al. 8 found that, in the absence of sunlight, air (55°C, 50 percent RH) contaminated with SO 2 (about
l5Oppm)andNO (l S0ppm) caused decidedly less fading than NO (150 ppm) alone. The investigators attributed
this difference to interactions between the gases. It is questionable, however, whether this result occurs at the low
concentrations normally existing in urban environments.
couper 25 demonstrated that severe gas-fume fading of a sensitive blue dye on acetate rayon bears a strong
resemblance to sunlight fading. This evidence suggested that oxidation in addition to direct reactions (diazotiza-
tion and nitrosation) between pollutants and dyes, is a more important gas-fume reaction than was previously
realized.
In laboratory studies, Greenspan and Spoerri 20 found that essentially pure NO and NO 2 were both capable
of fading sensitive dyed acetate fabrics, but that NO 2 was by far the more aggressive and powerful. In their studies,
Salvin et al. 24 attributed practically all fading to NO 2 . They showed that the mechanism of gas fading on acetate
rayon is the relatively large absorption of NO 2 by this material and the low rate of reaction with it. The gas is,
therefore, free to diffuse through the fibers and attack vulnerable dyes.
Gas-Fired Clothes Dryers
In the mid-1950’s, the textile industry learned that dyed fabrics other than acetate and wool are vulnerable
to fading by air contaminants. This conclusion was reached when dye chemists investigated a series of complaints
that some colored (mainly blues) cotton fabrics were fading during the drying cycle in home gas-fired clothes
dryers. 26 They traced the fading to NO formed during the combustion of natural gas used to heat the dryers.
Fading occurred only while the textile materials were moist. Subsequent research (about 10 years later) confirmed
the gas-dryer fading problem and revealed that NO levels (expressed as NO 2 ) in such dryers ranged from 1.1 to
3.7 mg/mi (0.6 to 2 ppm). 27
Smog Study
One of the earliest field exposures designed to assess the effects of air contaminants on dyed fabrics was con-
ducted in the summer of l956.2 Prompted by an increasing number of inquiries on fading, the Pacific Southwest
Section of the AATCC carried out this study to detennine the extent to which smog conditions may affect dyed
textile fabncs They selected 17 dyed fabrics, representing various classes of dyes and all the major fibers, and ex-
posed them at two sites in the Los Angeles area, one considered a “heavy” smog area and the other a “light” smog
area. The investigators placed two exposure chambers at each site. When closed, the chambers were thoroughly
sealed; when opened, the fabric samples in the chambers were shaded from sunlight but exposed to the ambient air.
One chamber at each site was opened only on smog days, the other only on “no-smog” days.
After exposure for 152 hours during smog days, 11 fabrics (acetates and nylons) developed visual color
changes at the heavy smog site. At the light smog site, six fabrics developed color changes and the fading was less
pronounced. Exposure for 152 hours during no-smog days produced visual color changes in six fabrics at the heavy
smog site and in four fabrics at the light smog site. Results of this study clearly demonstrated that color changes
re a function of smog concentration since the major pollutants in smog are NO and 03. The investigators made
no attempt to determine which pollutants caused fading in the individual fabrics.
AATCC Laboratory and Field Exposures
For many decades, the textile industry has been using outdoor lightfastness testing as a means of evaluating
the fading characteristics of dyes. During lightfastness tests in the mid- and late-1950’s, variations in color change
28 EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
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were frequently observed on some dyed fabrics when exposed to equivalent amounts of sunlight and similar weather
conditions but at different localities. 10 — 11 This abnormal behavior as a function of location was particularly evident
in certain direct dyes on cotton and acid dyes on nylon. These observations prompted the AATCC Committee on
Colorfastness of Textiles to Atmospheric Contaminants to conduct laboratory and field studies to assess the effects
of air contaminants as a cause of anomalous fading.
The laboratory research included exposing a range of dyes on nylon, wool, and cellulosic fibers to the
standard gas-fading procedure. 9 The investigators found that the most significant fading occurred on several
direct-dyed cotton and viscose rayon fabrics. They concluded that ambient levels of N0 existing in urban environ-
ments could be responsible for the anomalous results observed during lightfastness tests.
The AATCC Committee followed up the laboratory research by conducting service exposure trials in urban
and rural areas.’ 012 (Details of methodology have been described previously in this chapter.) The Committee
found that a number of dyed fabrics, including cotton and nylon in addition to acetate and wool, changed color.
Furthermore, color changes were most pronounced in areas where N0 and 03 were both present. They concluded
that (1) ambient levels of air contaminants, especially in urban areas, caused many of the observed color changes;
(2) dyes vary in their vulnerability to chemical change by pollutants: and (3) color changes as a result of pollutants
lead to variable results in lightfastness testing. The investigators suspected that, given acidic conditions, even
minute quantities of N0 would react to produce irreversible color changes in fabrics. 11
A subsequent, more comprehensive, field study was conducted jointly by the AATCC and air pollution
investigators with the Environmental Protection Agency. 13 (Details of this study have been described previously
in this chapter.) An analysis of the results showed that NO 2 appeared to be one of the pollutants that caused
fabrics to fade and that it was significant for seven of the exposed fabrics, though it was not necessarily the only
pollutant responsible. In many cases, however, it was impossible to separate the effects of NO 2 , as these were con-
founded with the effects of other pollutants.
Cellulosic Fabrics
The laboratory and field exposures furnished additional evidence of the type of fading observed on some
dyed cotton fabrics after exposure in domestic gas-fired clothes dryers. The exposures also lent credence to com-
plaints that some dyed cotton and rayon fabrics faded in warehouses and on the shelves of retailers; 29 textile
people, however, tended to attribute this fading to light. The complaints, as well as the field exposures, revealed
that fading occurred in certain blue and green shades, representing dyes from four major classes: direct, sulfur, vat,
and reactive dyes. Laboratory exposure of these shades to the standard gas-fading test procedure did not normally
produce fading. l’his test procedure, however, was designed to evaluate dyed acetate fabrics and has no provisions
for controlling relative humidity because humidity is not a critical factor in acetate fading. Researchers, therefore,
conducted follow-up laboratory exposures using the gas-fading test procedure under high-humidity conditions
(probably greater than 50 percent). The results were dramatic; the same concentrations of N0 that were previously
ineffective produced under high humidity color changes that generally agreed with the field results. A somewhat
different NO test procedure used in Europe results in high humidity conditions and has produced color changes
on sensitive dyed cellulosic fabrics. Presently, the textile-dye industry in the United States is considering modifying
the gas-fading test procedure to call for controlled-humidity conditions.
Controlled-Environment Study
Beloin 15 offers further confirmation of the fading effects of NO on sensitive dyes. He exposed 20 selected
dye-fabric combinations for 12 weeks to various controlled environments of clean air contaminated with individual
pollutants, including NO and NO 2 . Nitric oxide concentrations were 120 yg/m 3 (0.1 ppm) and 1200 pgJm 3 (1.0
ppm); NO 2 concentrations were 90 Lg/m 3 (0.05 ppm) and 940 jAg/rn 3 (0.5 ppm). As in previous research, Beloin
found thatNOwasaninsignificantcausein the fading of these fabrics. On the other hand, NO 2 was the most potent
Effects of Air Pollutants on Textile Dyes and Additives 29
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pollutant evaluated and was responsible for the greatest amount of fading on 13 of the fabrics. Fading occurred on
cotton, rayon, acetate, and nylon fabrics, the rates of fading decreasing with time.
While the high exposure levels of NO 2 produced the most pronounced fading effects, low levels still caused
readily visible color changes in a number of the fabrics. Relative humidity and, to a lesser extent, temperature were
signifIcant factors in accelerating fading. The exposure results also showed that fading in most cases is dependent
on the nature of the fiber substrate. Acetate fabrics dyed with Disperse Blue 3 faded two to five times more than
nylon fabrics dyed with the same dye. Likewise, Disperse Blue 27 on acetate faded severely, but the same dye on
polyester did not fade.
Discoloration of White Fabrics
A recent problem, which has received little publicity but which is of considerable concern to the textile
industry, is the yellow discoloration of pastel-colored or undyed white fabrics 2731 These fabrics may be woven
from any number of common fibers, but most of the discoloration has occurred on nylon, acetate, and permanent-
press (polyester-cotton) materials. Discoloration has usually occurred on items in storage or on display, including
dresses, shirts, curtains, and lingerie. Returned items have represented major losses to some textile companies.
Since discoloration occurs mostly on white fabrics, dyes were ruled out as a source of the problem. Investi-
gators turned to various additives, which are applied to fibers and fabrics to enhance certain properties. The addi-
fives tested included optical brighteners; cationic, antistatic, and soil-release finishers; softeners; and resinous proc-
essing agents. When tested by standard laboratory procedures, including the gas-fading procedure, many of these
additives yellowed on exposure to NOR. High relative humidity proved to be an important factor. Washing the
fabrics sometimes removes the yellow discoloration, but this is impractical for items that yellow in warehouses or
on display. The problem is best solved by selecting resistant additives. Such selections may be more expensive, but
the textile industry and retailers recognize that some action must be taken to avoid an increasing number of com-
plaints.
Protective Measures
To counteract the effects of gas fading, the textile industry has attacked the problem on two fronts: a search
for resistant dyes and a search for gas-fading inhibitors. Dye chemists have been trying for several decades to syn-
thesize acceptable dyes that would resist gas fading. Although gas fading is not limited to one dye class, research
efforts have centered mainly on developing replacements for the sensitive anthraquinone disperse dyes for acetate
fibers. These dyes are not equally sensitive to gas-fading; many shades are sufficiently resistant to meet all reason-
able commercial and domestic needs adequately. Shades that are sensitive are mainly those in the blue range of the
spectrum, especially the light and medium blues; they become redder on exposure to NOR. Not all blues are sensi-
the, however, and some offer good resistance. The search for resistant blue disperse dyes received added impetus
with the development of polyester fibers. Anthraquinone dyes possess excellent affmity for these fibers, but certain
blue dyes with good lightfastness on acetate have unusually poor lightfastness on polyester. This fact emphasizes
how fastness properties are dependent to a large extent on fIber substrate. 32
Researchers have developed a number of “gas-fast” blue dyes, mainly by modifying the anthraquinone
structure. This approach was desirable because dyes based on the anthraquinone structure possess excellent dyeing
and lightfastness properties when applied to acetate fibers. On field testing these newly developed dyes, however,
investigators found that ambient levels of ozone caused fading in some of them. 33 By further modifying the
anthraquinone structure, dye chemists were able to develop a limited number of disperse dyes that retained their
resistance to gas fading, but were more resistant to ozone fading. Fortunately, as gas-fading resistance increased,
resistance to ozone fading increased, as did lightfastness on polyester fibers. ’ 35
The resulting dyes are now widely used despite their higher cost, low color buildup, and increased processing
difficulties. For economic reasons, they are generally used only for light and medium shades on some moderate
30 EFFECFS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
-------
and most higher-priced fabrics; their poor color buildup precludes their use in dark shades, except for the most ex-
pensive fabrics.
The added cost and greater processing difficulties of the more resistant dyes brought about increased use of
gas-fading inhibitors, especially on moderately priced fabrics. Inhibitors were initially developed for use on acetate
fabrics, and today they are still used primarily’ on these fabrics. They are basic compounds that are applied to dyed
fabrics to give them prolonged protection by either maintaining an alkaline condition on fabric surfaces or by
reacting preferentially with NO .
Two types of inhibitors are widely used: fugitive and subsLantive. 24 ’ 36 ’ 37 Fugitive inhibitors, which include
water-soluble ahphatic amines and alkaline salts, are applied to dyed fabrics during the finishing operations. These
inhibitors effectively protect dyed fabrics by maintaining an alkaline condition on their surfaces gas-fading reac-
tions take place rapidly when surface conditions become acidic. Fugitive inhibitors have a serious drawback, how-
ever, because they are water soluble and subsequent washing by the consumer removes the protection. Nevertheless,
such inhibitors serve a useful purpose by protecting fabrics during conversion into end products, storage, and display
by retailers. They also can be used effectively on goods that are infrequently dry cleaned, such as women’s dresses.
Some fugitive inhibitors have a disadvantage besides water solubility in that they greatly reduce the Iightfastness of
direct and reactive dyes, some of which have been used to dye blends of acetate and cellulosic fibers.
Substantive inhibitors are aromatic amines that have an affinity for fibers and, therefore, are applied during
the dyeing process. They are sometimes called permanent or codyed inhibitors. Although compounds initially
found useful as inhibitors are weakly basic, they protect fabri’ s by preferentially reacting with NO , ; consequently,
they delay the onset of actual fading enough to prevent complaints in all but the most severe cases of contamination.
The reaction product, however, has a light yellow color tha’ may or may not (depending on depth of shade and
quantity of inhibitor used) impart an objectionable discoloration to fabrics These inhibitors are not useful on
pastel shades since the yellowish cast would be just as objectionable as gas-fading changes (blue shades will turn
green instead of red). They also reduce the lightfasiness of c:ertain dyes for acetate fabrics.
The shortcomings of these earlier substantive inhibite rs led chemists to develop new ones that were both sub-
stantive and nondiscoloring. The newer inhibitors posses; less affinity for fibers, however, and thus provide less
protection than the earlier ones. As a result, their overall effectiveness in many cases is limited. Unfortunately, they
are least effective on fabrics colored with the more sensiti’re gas-fading dyes.
A successful means of preventing gas fading in synthetic fibers is to add colored pigments to the spinning
solutions prior to the formation of the fibers into filame nts or yarn. Pigments are generally resistant to the effects
of air pollutants. Pigmented fibers and yarns can presnt problems, however, since there is a time lag of 6 to 8
months between their manufacture and their final conve rsion into end products. During this period, fashion colors
can change dramatically. If fabrics are left undyed, on the other hand, they can then be dyed with the “in” fashion
colors and converted into end products.
Although ways exist for mitigating the effects of ga:; fading, incidents still occur. 37 ’ 38 Fading of acetate lin-
ings on men’s suits has been a particularly vexing probleni. The most costly incidents have taken place during the
storage of fabrics and end products in warehouses, with the result that entire truckloads of materials either had to be
sold at prices below cost or returned to the producers. In an effort to ensure quality, some synthetic fiber producers
offer the use of their fiber trademarks on labels only to ( ustomers that produce fabrics meeting established color-
fastness performance standards for both pollutants and sunlight. 36 ’ 38 Consumers as well as producers benefit when
such steps are taken.
OZONE
Discovery of “0-Fading”
Although dye chemists identified SO 2 and NO as possible dye fading agents during the early 1900’s, it was
not until the mid-1950’s that Salvin and Walker 33 discovered that ozone was a cause of fading. The discovery came
Effects of Air Pollutants on Textile Dyes and A dditives 31
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about as a result of the field testing of newly synthesized blue disperse dyes that had previously shown a high re-
sistance to NO when evaluated by the standard AATCC gas-fading laboratory test method. Field testing was con-
ducted to determine if the performance level of these new dyes was as favorable in actual use as that indicated by
the accelerated gas-fading tests. In a preliminary 1-year service trial, investigators placed draperies in homes located
in areas known to have either high or low levels of INOX. The draperies were made from acetate fabrics dyed a variety
of shades, with one of these newly developed eyes (Disperse Blue 27) as a color component. After exposure, a
number of draperies showed a marked degree ci fading. Furthermore, fading was generally greater than could be
predicted on the basis of lightfastness and gas-fading laboratory tests. Color changes were most apparent on light
shades and, in many instances, occurred in homes where NO levels were low. The investigators reasoned that
some other atmospheric agent caused the fading.
As a result of this preliminary study, a móce thorough and extensive service trial was conducted. Acetate
draperies were dyed different colors, with some shades containing the new gas-fast dye, Disperse Blue 27, as one of
the color components; others contained gas-fading sensitive dyes along with inhibitors. The draperies were placed
in homes in Pittsburgh, Pennsylvania, an industrial complex noted for the prevalence of gas-fading; in Ames, Iowa,
a nonindustrial town known to have minimum levels of NON; and in Austin, Texas, a nonindustrial city where
natural gas is the main fuel used. After exposure fol 6 months, color changes were evident in many of the draperies
at all three locations and became even more pronounced at the end of 12 months. Color changes occurred in areas
of the draperies that were not exposed to sunlight. \ s was found in the preliminary service trial, draperies contain-
ing the gas-fading resistant blue-dye component faded as much, and in some cases more, at locations (Ames) having
low levels of NO than at locations (Pittsburgh) with higher levels. Relative levels of N0 were confirmed by rapid
reddening of gas-fading standard control samples in 1 ittsburgh and lack of reddening in Ames. Furthermore, at all
locations some draperies showed considerably more fading than accompanying gas-fading control samples. Much of
the observed fading was characterized by a bleached , washed-out effect, rather than the familiar reddening that
nitrogen oxides produce in most gas-fading sensitive dyes. Again, this anomalous behavior suggested that some
other oxidizing agent was responsible and was present a all sites, although concentrations appeared to be somewhat
less at Pittsburgh.
To describe this fading phenomenon, Salvin and Walker 33 coined a new term, “0-fading.” On reviewing the
various chemical constituents in the atmosphere that could produce this bleaching effect, they concluded that
ozone, or ozone in conjunction with other oxidizing agei ts, was the most likely cause on the basis of the following
suppositions, general observations, and laboratory investigntions:
1. Fading on gas-fading resistant dyes observed durwig the service trials in nonindustrial areas may be attrib-
uted to background levels of ozone, augmented by small amounts produced photochemically. O -fadiiij
was either absent or less evident in Pittsburgh because much of the atmospheric 03 was consumed in oxi-
dizing ambient SO 2 to SO 3 . Pittsburgh was knowi t to have above average levels of SO 2 .
2. Drapery fabric samples that were sensitive to Q-fa ding developed shade changes similar to the anomalous
effects produced during the service trials when they were exposed in a light-tight chamber containing
ozone generated from ozone lamps. Ozone did not fade dyed fabrics known to resist fading during service
trials.
3. Antioxidants applied to fabrics sensitive to 0-fad jng effectively inhibited the bleaching action of 03. Some
of the widely used gas-fading inhibitors are act lye antioxidants and consequently inhibit 0-fading as well
as gas-fading. This fact undoubtedly obscured earlier detection of the 0-fading phenomenon.
Salvin and Walker 33 also investigated the ozone-fatling characteristics of gas-fast Disperse Blue 27 on other
fibers: cellulose triacetate, polyester, acrylic, and nylon. Acrylic and nylon showed no evidence of fading. (A few
years later, however, researchers were to discover that nylon fibers dyed with Disperse Blue 3 develop pronounced
color changes when exposed to 03 in the presence of high :relative humidity.) The sensitivity of cellulose triacetate
and polyester fibers to 03 was found to be dependent upon the dyeing and finishing conditions used in processing
the fabrics. If these conditions are such as to ensure maxnium penetration of dyes into fibers, the resistance of the
fabrics to 0-fading will significantly increase. For the ;e fibers, therefore, heat treating, which increases dye
penetration and can be conducted during the dyeing and Finishing operations, is necessary to ensure greater resist-
ance to 0-fading. This treatment changes the internal arra ngement of fiber molecules, resulting in a more closely
32 EFFECTS OF AIR POL1 LJTANTS ON TEXTILE FIBERS AND DYES
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packed intermolecular structure that slows down the diffusion rate of 03. For polyester fibers) the use of carriers
also increases dye penetration.
In evaluating other disperse dyes, the researchers found that 0-fading, like gas-fading, occurs to the greatest
degree with anthraquinone blues and some reds and, to a lesser extent, with several of the azo reds. They also noted
that most of the substantive gas-fading inhibitors are sufficiently strong antioxidants to reduce the rate of 0-fading.
For the highest overall level of colorfastness toward atmospheric fading, gas-fast dyes together with gas-fading
inhibitors or other antioxidants are recommended.
Standard Test Method
Once ozone had been established as the principal active agent in the atmosphere responsible for 0-fading, the
AATCC Committee on Colorfastness to Atmospheric Contaminants took steps during the late 1950’s and early
1960’s to develop a testing method. Their efforts culminated with the approval and publication in 1963 of a pro-
cedure that presently is designated as Test Method 109-1972, Colorfastness to Ozone under Low Humidities. 23
This method has been useful in predicting fabric performance upon service exposure to 0-fading environments. It
calls for imu1taneously exposing test specimens and an 0-fading control sample (AATCC Control Sample No. 109)
in a chamber containing circulating air contaminated with 03. Exposure, which is carried out at ambient room
temperatures and relative humidities not exceeding 65 percent, continues until the control sample shows a color
change corresponding to a standard of fading (AATCC Standard of Fading No. 109). This exposure period consti-
tutes one cycle, and the test specimens are said to have a treatment equivalent to 4 to 6 months of actual exposure
to moderate lewis of ambient ozone. 39 If the test specimens do not fade appreciably, the cycles are repeated until
the specimens show a definite color change or until a prescribed number of cycles has been completed. Ozone may
be generated by 03 lamps, or by a high-voltage insulated-grid design that produces 03 by corona discharge. The
test method does not specify the 03 exposure concentration; generally, however, it does not exceed 100 parts per
hundred million (pphm) and normally is about 25 pphm when commercially available equipment is used. 40
The control sample, frequently called the ozone-fading control ribbon, is a medium-gray cellulose triacetate
fabric, prepared as a tertiary shade by dyeing with 0-fading vulnerable Disperse Blue 27, relatively resistant Disperse
Red 35 ,and resistant Disperse Yellow 42. The sample shows 0-fading mainly by a loss of blue and takes on a bleached,
washed-out silver gray appearance. The bleaching effect is the result of the almost colorless products that 03
produces when it reacts with vulnerable dyes. The loss of blue is more readily recognized in the tertiary shade than
in a single shade of blue. Fading does not proceed uniformly with time; it is more apparent in the earlier stages of
the fading cycle. Slightly more than two cycles produce sufficient fading to cause consumer complaints.
Anomalous Fading During Service Trials
The discovery that 03, in addition to N0 , is a prime cause of fading was useful in explaining much of the
anomalous fading of certain dyed fabrics that was observed during subsequent lightfastness testing and service
trials. Abnormal fading was lust noticed during lightfastness testjng in the late 1950’s.41 Certain fabrics exposed
at different nationwide localities but to the same total amoUnt of solar radiation (Langleys) revealed unexpected
fading. For example, a decidedly larger number of fabrics faded more at a semirural site near Sarasota, Florida, than
at a semirural site near Phoenix, Arizona, or at a semi-industrial site in greater Chicago, Illinois. Abnormal fading
was especially prevalent in certain direct dyes on cotton and acid dyes on nylon. An analysis of the temperature
and relative humidity conditions during exposure was only partly helpful in explaining the abnormal fading. Other
factors were influencing the color change and air contaminants were suspected.
Anomalous fading behavior was also observed in a follow-up field study that Schmitt conducted.l°A 2 He
exposed cotton fabric samples, dyed with certain direct dyes, for 24 days in Los Angeles, Califomia; Fair Lawn,
New Jersey; Sarasota, florida; and Phoenix, Arizona. Samples were exposed to !direct sunlight under glass and also
shaded from direct sunlight. The exposure design allowed intimate contact betw!en fabric samples and ambient
Effects of Air Pollutants on Textile Dyes and Additives 33
-------
air. As was expected, pronounced fading developed on shaded samples exposed in the photochemical atmosphere
of Los Angeles. At the semirural site near Sarasota, however, Schmitt also observed appreciable fading on the
shaded samples; in some cases, it was equal to the fading observed from exposure to direct sunlight. He reasoned
that the high relative humidity normally prevailing in florida was the controlling factor in causing abnormal fading.
Additional research showed that high humidity by itself caused only a portion of the observed fading. More im-
portant, Schmitt concluded, was the resulting increase in the equilibrated moisture content of the cotton fabrics.
The high moisture content promoted and accelerated the absorption and reaction of air contaminants with vulner-
able dyes within the fibers. Schmitt stated that much of the abnormal fading observed in Florida appeared to be
caused by air contaminants. Later studies indicated that ozone was largely responsible for this anomalous fading in
Sarasota 12
In service exposure trials in 1961, the AATCC Committee on Colorfastness of Textiles to Atmospheric Con-
taminants exposed a wide range of dyed fabrics for 90 days in the absence of sunlight, but with free access to am-
bient air. 12 The exposure test sites were located in I_os Angeles, Chicago, Phoenix, and Sarasota. (Additional de-
tails were given previously in this chapter.) A number of dyed fabrics faded excessively in Los Angeles because of
the combined action of relatively high levels of 03 and N0 . Fading was generally less severe on like fabrics ex-
posed in Chicago, where th atmosphere had lower levels of 03 but fairly high levels of N0 . Anomalous fading
was observed at the semirural sites in Phoenix and Sarasota. Since both areas were essentially free of NO (indicated
by a lack of reddening of N0 control samples) but contained appreciable amounts of 03 (indicated by the bleach-
ing effect on 0-fading control samples), the observed fading was attributed largely to 03. The degree of fading,
however, was greater in Sarasota than Phoenix. The investigators concluded that high humidity, normally found in
Florida, accelerated the ozone-dye reaction as Schmitt had previously suggested.
In the spring of 1963, investigators exposed a number of dyed fabrics in Sarasota in order to compare their
fading characteristics both in direct sunlight and when shaded from direct sunlight 2 Exposure for 30 days to this
humid, semirural environment, contaminated with moderate levels of 03 and essentially free of N0 showed that
those dyed fabrics most susceptible to 0-fading were also those that faded the most in sunlight. This result was not
surprising since fading by sunlight is largely a photochemical oxidation reaction.
The results of the service trials emphasized the importance of 03 as an effective fading agent, and focused
attention on the critical role of relative humidity. They also alerted the textile industry to the possibility of po-
tential consumer complaints. Such complaints, which were not long in coming, concerned mainly two distinctly
different textile materials: polyester/cotton permanent-press fabrics and nylon carpets. In both cases, complaints
began to appear in the early 1960’s. These problems were not generally made known, however, because adverse
publicity could have jeopardized the use of these fibers before researchers had an opportunity to assess the cause of
fading and take corrective measures.
Permanent-Press Fabrics
Initial complaints concerning polyester/cotton permanent-press fabrics were a result of fading on the folds
and edges of slacks stored in warehouses or on the stock shelves of retail outlets. 31 ‘ Incidents occurred in various
locations including California, Texas, and Tennessee. Because of the volume of garments involved, some producers
suffered heavy economic losses. Fading was marked by a loss in blue, along with a slight increase in red, suggesting
that 03 and, to a lesser degree, N0 may have been the active fading agents since sunlight was obviously not a fac-
tor. This conclusion did not seem reasonable, however, because most vat dyes on cotton and disperse dyes on
polyester fibers are resistant to fading by common air contaminants. Furthermore, fading occurred only on fabrics
that had been made into finished products and cured to set the permanent-press resin; fading had not been observed
during the temporary storage of dyed fabrics, either before or after treatment with permanent press resins (prior to
curing).
After a thorough investigation that included extensive laboratory tests, researchers found ozone to be the
major fading agent, with N0 also capable of causing fading but to a lesser extent. The fading mechanism, which is
unique and complex, takes place as a result of the curing operation and involves the disperse dyes used to color the
34 EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
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polyester fibers rather than the vat dyes on the cotton. During curing, some disperse dyes partially migrate to the
permanent press finish, which is a combination of reactant resins, catalysts, softeners, and nonionic wetting agents.
The dispersed dyes migrate to the solubilizing agent (nonionic surfactants and softeners) in the finish and are then
in a media in which fading by air contaminants can easily occur. Softeners are especially effective media for absorb-
ing gases.
The choice of catalyst used in the finish plays an important role, as the migration of disperse dyes increases
significantly when magnesium chloride is used as a catalyst rather than zinc nitrate. Magnesium chloride is capable
of forming complexes with certain anthraquinone disperse dyes (blues and red), and these complexes are soluble in
the resin finish.
The blue disperse dyes that faded on the permanent-press fabrics are the same ones that, when used on cellu-
lose acetate, are sensitive to fading by 03 and N0 . Fading takes place rapidly on cured garments dyed with vul-
nerable disperse dyes and finished with a resin system containing a magnesium chloride catalyst. Garments have
faded after storage in warehouses for only 10 days.
Several remedial measures are available that, if followed, will markedly reduce the possibility of fading
permanent-press products. These include: (1) replacing the vulnerable anthraquinone dyes with dyes that resist
migration (high sublimation resistance), such as the azo disperse dyes; 44 ’ 45 and (2) carefully selecting the materials
that make up the permanent press finish; that is, avoiding magnesium chloride as a catalyst and using softeners and
surfactants that show less tendency to serve as solubiizing agents. 46 As long as the textile industry takes these
steps, fading of permanent-press garments by 03 and N0 can be essentially eliminated.
Nylon Carpets
Fading complaints concerning nylon carpets originated mainly in the warm humid areas from Texas to Florida
and, as a result, became known as “Gulf Coast fading. ” 31 ’ 43 In one case, nylon carpeting in a Texas apartment
complex faded 30 days after installation. A few incidents were noted also along the East Coast and in the Los Ange-
les area. Fading occurred on carpets manufactured from both nylon 66 and nylon 6 fibers. Disperse dyes were
used because many possessed the easy leveling properties so necessary to avoid dye streaks. Fading took place
largely on those carpets dyed with Disperse Blue 3 as a color component. Avocado, a tertiary-dyed dull-green
shade, was a particularly sensitive color, and fading was characterized primarily by loss in blue as the green color
gradually turned to a dull orange shade.
Investigators eliminated sunlight as a primary cause of fading since complaints occurred in rooms where light
intensity was low. Exposure of carpet samples to AATCC standard test methods for 03, N0 , and SO 2 also failed
to duplicate the color change. Since fading complaints occurred in humid environments and previous lightfastness
testing and service trials established that conditions of high relative humidity promote fading of certain dyes by
ozone, the investigators next exposed carpet samples to 03 in the presence of high relative humidity (85 to 90 per-
cent). Under these conditions, pronounced fading took place on those samples containing Disperse Blue 3, and the
fading was similar to color changes observed in homes along the Gulf Coast. Later experiments showed that relative
humidity must be somewhat above 65 percent for pronounced ozone fading to occur.
Similar avocado carpet samples were also exposed outdoors in Florida. Samples were shaded from direct sun-
light and placed 10 inches from the ground to ensure exposure to maximum ambient relative humidity. Exposure
periods ranged from I week to 30 days. The carpet samples developed pronounced color changes. Fading was
attributed to 03 on the basis of observed color changes in ozone control samples and lack of reddening of nitrogen
oxides control samples.
Research on the mechanism of fading showed that the heat-treating method used to texture nylon filaments
was a most important factor. Texturing geometrically modifies or otherwise alters fibers to change and enhance
Effects of Air Pollutants on Textile Dyes and Additives 35
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certain basic physical characteristics such as bulk and resilience. Researchers found that the rate of fading by 03
was significantly less in nylon fibers textured by dry heat than in those textured by steam. Steam texturing pro-
duces a somewhat open fiber structure that more readily absorbs moisture, especially when the humidity is high,
which results in increased swelling and greater surface area. Increased fiber surface area and moisture content favor
increased 03 diffusion and greater subsequent fading rates.
Today, Gulf Coast fading can be mitigated or totally prevented by (1) using nylon fibers that have been
modified and textured to decrease the accessibffity and diffusion rate of ozone; and (2) using dyes having improved
resistance to ozone fading. Nylon carpet fiber producers recommend that selected acid dyes having satisfactory
leveling properties be used for maximum resistance to fading. For intermediate resistance, they recommend the
use of improved disperse dyes or combinations of acid dyes and improved disperse dyes. Under no circumstances
do they endorse the use of Disperse Blue 3.
Cellulosic Fabrics
Although less serious than the previously described problems, scattered incidents of fading on cotton and
rayon fabrics also came to the attention of the textile industry during the early 1960’s and are still occurring today.
Consumer complaints have included fading of direct dyes on cotton upholstery, of sulfur dyes on corduroy fabrics,
and of reactive dyes on printed draperies. 43 Previous outdoor service trials had shown that a number of dyed
ceilulosic fabrics faded even though their exposure to standard laboratory test procedures failed to produce signifi-
cant color changes. As was true for nylon carpets, researchers found that relative humidity was the controlling
factor. Exposing certain dyed cellulosic fabrics to high-humidity environments contaminated with 03 or NOR, or
combinations of these pollutants, produced fading similar to that observed during service trials and on returned
“consumer complaint” articles.
High Humidity Test Method
The unexpected fading of nylon carpets by 03 was a costly experience for the textile industry and demon-
strated the need for a test method to evaluate colorfastness to 03 under high-humidity conditions. The AATCC
Committee on Colorfastness to Atmospheric Contaminants fulfilled this need during the late 1960’s by developing
Test Method 129-1972, Colorfastness to Ozone in the Atmosphere under High Humidities. 23 The principles and
procedures involved in this test are similar to previously described Test Method 109-1972 except that exposure con-
ditions are maintained at 85 to 90 percent relative humidity and 40 ± 5°C, with ozone concentrations ranging from
374 Lgfm 3 (20 pphxn) to 1680 pg/rn 3 (90 pphin). The control sample is an avocado shade of nylon 6 fine-gauge
tufted carpet tertiary-dyed with Disperse Blue 3, Disperse Red 55, and Disperse Yellow 3. The standard of fading
used is similar carpet material dyed to a shade representing an average degree of fading that control samples develop
af(er 30-day exposures in southern Florida in the absence of sunlight for a 1-year period. Control samples yield
thade changes after two cycles that are equivalent to changes observed on consumer complaint fabrics from Florida
and Los Angeles. 47 This test method has been useful in predicting the behavior of textile materials in actual service
and in preventing costly, wide-scale fading by ozone.
The U. S. Department of Housing and Urban Development is planning to include a carpet performance
standard for resistance to 03 fading as part of the FHA carpet certification program. AATCC Test Method 129-
1972, or a modification thereof, may be the designated test procedure.
Recent Exposures
Environmental Protection Agency investigators, in cooperation with the AATCC, conducted field and
laboratory exposures of selected dyed fabrics. In the field study 13 (discussed previously in this chapter), ozone
seemed to be one of the pollutants causing fading and was a significant factor (though not necessarily the only
36 EFFECTS OF AIR POLLUTANTS ON TEXI’ILE FIBERS AND DYES
-------
pollutant responsible) in the fading of the exposed fabrics. It was generally impossible to separate the effects of 03
because they were confounded with the effects of other pollutants, especially NOR.
The controlled-environment laboratory study 15 was designed to assess the effects of common air pollutants,
temperature, and relative humidity on the colorfastness of certain dyed fabrics selected from those exposed during
the field study. (Additional laboratory exposure details were discussed previously in this chapter.) Fabric samples
were exposed to two concentrations of ozone: 100 pg/rn 3 (0.05 ppm) and 980 pg/rn 3 (0.50 ppm). As might be
expected, under similar exposure conditions, high ozone levels pToduced significant fading in more fabric samples
than low levels, and, furthermore, the color changes were more pronounced. Low ozone levels, nevertheless, pro-
duced visible fading in a number of sensitive fabrics, an important finding since the low levels were similar to levels
frequently occurring in metropolitan areas. The study also demonstrated that high relative humidity (90 percent),
and, to a lessei extent, high temperature (32° C) are significant factors in promoting and accelerating ozone-induced
fading, thus confirming what investigators observed during previous service trials. Rate-of-fading curves did not
follow any consistent pattern, but were obviously dependent on such factors as color and type of dye, fiber sub-
strate, and enviromnental conditions.
REFERENCES FOR CHAPTER 3
1. King, A. 1. The Effect of Sulphur Dioxide on Azo Dyestuffs and a Proposed New Standard Test for Fastness
to Stoving. J. Soc. Dyers Colour. 44: 14.18, January 1928.
2. Goodall, F. L. Gas Fading. J. Soc. Dyers Colour. 51:126-127, April 1935.
3. Cunliffe, P. W. The Fading of Dyed Textiles—I. 3. Soc. Dyers Colour. 46:08-111, April 1930.
4. King, A. T. Chemical Effects of the Natural Sulphur in Wool on the Fading of Azo Dyestuffs. J. Soc. Dyers
Colour. 44:233-236, August 1928.
5. Goodall, F. L. Sulphite Faults and Sulphur Dioxide Effects in Theory and Practice. J. Soc. Dyers Colour.
48:118.124, May 1932.
6. Jones, J. I. M. Further Notes on the Tendering and Fading of Cellulose Materials on Exposure. J. Soc. Dyers
Colour. 51:285-299, August 1936.
7. Row, F. M. and K A. J. Chamberlain. The “Fading” of Dyeings on Cellulose Acetate Rayon. J. Soc. Dyers
Colour. 53:268-278, July 1937.
8. Ray, F. K., P. B. Mack, F. Bonnet, and A. H. Wachter. A Comparison of the Effect on Rayon Fabrics of Vari-
ous Gases under Controlled Conditions. Amer. Dyest. Rep. 37:391-396, June 1948.
9. Salvin, V. S. Effect of Atmospheric Contaminants on Lightfastness Testing. Amer. Dyest Rep. 47:450.451,
June 1958.
10. Salvin, V. S. Effect of Air Pollutants on Dyed Fabrics. 3. Air Poll. Contr. Assoc. 13:416-422, September
1963.
11. Salvin, V. S The Effect of Atmospheric Contaminants on Ughtfastness. J. Soc. Dyers Colour. 79:687-696,
December 1963.
12. Salvin, V. S. Relation of Atmospheric Contaminants and Ozone to Ughtfastness. Amer. Dyest. Rep.
53:33.41, January 1964.
13. Beloin, N. J. Fading of Dyed Fabrics by Air Pollution: A Field Study. Text. Chem. Color. 4:4348, March
1972.
14. Ajax, R. L., C. J. Conlee, and J. B. Upham. The Effects of Air Pollution on the Fading of Dyed Fabrics. 3.
Air Pol. Contr. Assoc. 17:220-224, April 1967.
15. Beloin, N. J. Fading of Dyed Fabrics by Air Pollution: A Chamber Study. Text. Chem. Color. 5:128-133,
July 1973.
Effects of Air Pollutants on Textile Dyes and Additives 37
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16. Giles, C. H. The Fading of Colouring Matters. J. Appi. Chem. 15:541-550, December 1965.
17. Cady, W. H. Gas Fading of Dyes. Amer. Dyest. Rep. 28:333-335, June 1939.
18. Seibert, C. A. Atmospheric (Gas) Fading of Colored Cellulose Acetate, Part I. Amer. Dyest. Rep. 29:363-
374, July 1940.
19. Seibert, C. A. Atmospheric Gas Fading of Colored Cellulose Acetate, Part II. Amer. Dyest. Rep. 31:647-
649, December 1942.
20. Greenspan, F. P. and P. E. Spoem. A Study of Gas Fading of Acetate Rayon Dyes. Amer. Dyest. Rep. 30:645.
665, November 1941.
21. Ray, F. K., P. B. Mack, and A. H. Wachter. Evaluation of Uncontrolled Gas Fading Equipment. Amer. Dyest.
Rep. 37:287-289, May 1948.
22. Ray, F. K., P. B. Mack, F. Bonnet, and A. H. Wachter. A Study of the Effect of Certain Variables on Gas
Fading Tests Made Under Controlled Conditions. Amer. Dyest. Rep. 37:529-536, August 1948.
23. AATCC 1972 Technical Manual, Vol. 48. Amer. Assoc. of Text. Chem. Colour. Research Triangle Park,
North Carolina.
24. Salvin, V. S., W. D. Paist, and W. J. Myles. Advances in Theoretical and Practical Studies of Gas Fading.
Amer. Dyest. Rep. 41:297-304,May 1952.
25. Couper, M. Fading of a Dye on Cellulose Acetate by Light and by Gas Fumes. Text. Res. J. 21:720-725,
October 1951.
26. A Study of the Destructive Action of Home Gas-Fired Dryers on Certain Dyestuffs. Amer. Dyest. Rep.
45:471, July 1956.
27. McLendon, V. and F. Richardson. Oxides of Nitrogen as a Factor in Color Changes of Used and Laundered
Cotton Articles. Amer. Dyest. Rep. 54:305.311, April 1965.
28. Smog Studies: Its Effect on Dyes and Fibers - Part 1. Amer. Dyest. Rep. 45:919-922, December 1956.
29. SaIvin, V. S. Testing Atmospheric Fading of Dyed Cotton and Rayon. Amer. Dyest. Rep. 58:28-29, October
1969.
30. Rabe, P., and R. Dietrich. A Comparison of Methods for Testing the Fastness to Gas Fading of Dyes on
Acetate. Amer. Dyest. Rep. 45:737-740, September 1956.
31. Salvin, V. S. Effect of Atmospheric Contaminants on Fabrics—Dyed and Undyed. Text. Qual. Contr. Papers
Amer. Soc. Qual. Contr., Textiles and Needle Trades Div. 16:56-64, 1969.
32. Todd, R. E., R. S. Asquith, and A. 1. Peters. The Influence of Fiber Substrate on the Fading Properties of
Nitrodiphenylamine Dyes. Amer. Dyest. Rep. 55:560-563, July 1966.
33. Salvin, V. S. and it A. Walker. Service Fading of Disperse Dyestuffs by Chemical Agents Other Than the
Oxides of Nitrogen. Text. Res. J. 25:571-585, July 1955.
34. Salvin, V. S. and R. A. Walker. Relation of Dye Structure to Properties of Disperse Dyes. Amer. Dyest. Rep.
4a:3s -43,July 1959.
35. Salvin, V. S. and R. A. Walker. Correlation Between Colorfastness and Structure of Anthraquinone Blue
Disperse Dyes. Text. Res. J. 30:383-388, May 1960.
36. Moussalli, F. S. and W. J. Myles. Gas Fading of Acetate and Triacetate Prints. Amer. Dyest. Rep. 54:1136-
1140, December 1965.
37. Gas Fume Fading. Dyer Text. Printer. 128 (2):89-90, July 1962.
38. Morley, D. J. Upholstery Fabric Fading by Impurities Present in the Air. Bull. Furniture md. Res. Assoc.
2-3, March 1967.
39. Salvin, V. S. Colorfastness to Ozone in the Atmosphere. Amer. Dyest. Rep. 52:39, August 1963.
38 EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
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40. Personal communication, Mr. Cameron Baker, Better Fabrics Testing Bureau, Inc. New York, New York.
41. Schmitt, C. H. A. Daylight Fastness Testing by the Langley System. Amer. Dyest. Rep. 51.664-675,
September 1962
42. Schmitt, C. H. A. Lightfastness of Dyestuffs on Textiles. Amer. Dyest. Rep. 49:974-980, December 1960.
43. Salvin, V. S. Ozone Fading of Dyes. Text. Chem. Color. 1:245-251, May 1969.
44. Salvin, V. S. The Effect of Dry Heat on Disperse Dyes. Amer. Dyest. Rep. 48:490-501, June 1966.
45. Salvin, V. S. The Sublimation Problem in Permanent Press Finishing. Amer. Dyest. Rep. 56:421-425, June
1967.
46. Schnider, F. F. and C. W. Schouten. The Interrelation of Dyes and Soil Release Finishes on Polyester/Cel-
lulosic Blends. Text. Chem. Color. 1:110-116, February 1969.
47. AATCC 1970 Technical Manual, Vol. 46. Amer. Assoc. of Text. Chem. Color. Research Triangle Park,
North Carolina. p. 20.
Effects of Air Pollutants on Textile Dyes and Additives 39
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CHAPTER 4
INDUSTRIAL AND COMMERCIAL AWARENESS
IMPORTANCE OF COMMUNICATION
Awareness by the textile industry of air pollution effects on textile fibers and dyes is an important aspect of
the overall effects problem, since the greater the knowledge and understanding, the more likely that corrective
measures will be taken. To a large extent, awareness depends on information provided by product users, and sim-
ilarly the industry, on uncovering new problems involving air pollution effects, must disseminate the data to in-
dustrial and commercial customers. These customers are then alert to the possibility that some of the damage
brought to their attention may be caused by air pollution, and they, in turn, are more likely to convey complaints
to the industry for subsequent follow-up investigation.
Despite the clear need for effective communication about the effects of air pollution on textiles, a vital ele-
ment is lacking: information from consumers. Unfortunately, they, as a group, do not register many complaints;
and, while they may openly discuss complaints with friends and neighbors, adversely affecting the reputation of
stores and product brand names, few complaints reach the retailers. This difficulty is intensified when those con-
sumers who do register complaints meet with little or no success; they become discouraged and develop an attitude
of futility. In essence, therefore, while retailers do receive a fair number of complaints, they represents only a small
fraction of total consumer dissatisfaction.
The fading of colored textile fabrics is a frequent complaint of consumers and may serve as an example of
their attitudes, since potential causes of fading include air pollutants in addition to sunlight, laundering, and dry
cleaning. Fading may take 6 to 12 months or more to develop, and consumers generally take a somewhat passive
attitude on discovering the problem. Many feel that fading, though objectionable, is normal and must be accepted.
They also may assume that, since they no longer have their sales receipt, it is too late to take effective action. The
few who do register complaints frequently meet resistance because many retailers tend to blame fading on sunlight,
an admittedly important factor but not necessarily the cause. Furthermore, retailers consider fading by sunlight a
shared responsibility. Often they make adjustments and return the goods to apparel or home-furnishings producers.
In most cases, the prr 1ucers take no further action because they have neither sufficient information to diagnose the
complaints nor facilities to determine the causes. It is more economical to pay for isolated complaints than to
undertake expensive diagnoses. Thus, lines of communication between consumers and producers break down to
the disadvantage of both. Consumers are dissatisfied with the performance of their purchases, and, consequently,
the merchandising efforts of retailers and producers in promoting quality performance and brand names become
less effective.
When the economics justify it, producers respond quickly to complaints. For example, when incidents in-
volve the possible fading or discoloration of fabrics or garments in warehouses or on display shelves of retailers, the
resulting complaints, whether made to fiber producers, fabric mills, or dyers and finishers, may become major
financial burdens, because thousands of items may be affected. Such complaints obviously receive immediate
attention, and subsequent investigations have produced important technical information, much of which has been
the basis for establishing industry.wide testing procedures. The American Association of Textile Chemists and
Colorists is actively engaged, for instance, in developing test procedures for examining the fading of colors front
exposure to atmospheric pollutants.
41
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AWARENESS
To measure the degree of awareness of the various textile-related industrial and commercial groups, Dr. Salvin
in conducting his textile-effects survey, made numerous inquiries to collect information on damage problems di-
rectly caused, or suspected of being caused, by air pollution. He solicited responses from producers of fibers,
fabrics, dyes, and finishes; fabric dyers and finishers; apparel, carpet, drapery, and upholstery manufacturers;
chain and department stores; laundry and dry cleaning establishments; trade and technical associations; con-
sumer groups; and Federal, state, and university research centers.
The survey showed that the degree of awareness of air pollution problems in the industry varied with partic-
ular textile areas of interest. In order to assess awareness effectively, Dr. Salvin divided the diverse industrial and
commercial respondents into five product-oriented groups: fiber products; dye and specialty chemical manufac-
turers; fabric mills, dyers, and processors; producers of apparel, home furnishings, and other goods; and consumer-
oriented groups.
Fiber Producers
Fiber producers (including both those concerned with manmade fibers and organizations that.supply, pro-
mote, and conduct research on natural fibers) are aware that air contaminants can produce serious problems.
Manufacturers of manmade fibers appear, however, to have a better understanding of these problems, probably
because dye fading (the major problem area) is much more prevalent on fabrics made from synthetic fibers than
natural fibers. They maintain close liaison with producers of dyes and textile specialty chemicals; some large
corporations even have divisions that manufacture both fibers and dyes. This close relationship is advantageous
because fiber producers, by introducing processing changes, may be able to modify their fibers so as to overcome
difficulties that become evident during dyeing operations. Fiber producers also work closely with fabric mills in
the mutual recognition of dye-fading and fabric-deterioration problems. In addition, producers of manmade fibers
find it in their interest to know as much as possible about their own fibers, as well as those of their competitors, in
order to promote and protect their brand names. Some producers require that fabrics made from their fibers and
carrying their brand names meet certain standards of resistance to fading by oxides of nitrogen and ozone.
Dye and Specialty Chemical Manufactures
Fabric mills encountering color-fading or fiber-deterioration complaints have traditionally submitted these
problems to dye manufacturers or suppliers of various textile specialty chemicals. As a result, these manufacturers
and suppliers as well as their trade association, The Dye Institute, are well aware of the problems associated with
air pollution. The major dye manufacturers have evaluated the fading resistance of their dyes against NOR,
acids, and ozone. Specialty chemical companies have developed numerous inhibitors and other additives to protect
dyed fabrics against air pollutants. Accordingly, these manufacturers and suppliers promote and publicize in
advertisements the virtues of their products in resisting the effects of air pollution.
Fabric Mills, Dyers, and Processors
The American Textile Manufacturers Institute is a trade association with an extensive membership consisting
of manufacturers, dyers, and processors of fabrics for use in apparel, home furnishings, and industry. Some of the
fabric manufacturers also produce finished consumer goods. In his survey, numerous cooperating members of this
organization furnished Dr. Salvin specific information on various problem areas caused by air pollution; thus,
definitely establishing that they were aware of the problem. This awareness was especially apparent in the case of
the major fabric mills, which are quality-conscious and are constantly endeavoring to identify their brand names
with quality products. Some mills, together with their associated dyehouses and finishers, must meet stringent
performance specifications that fiber producers, converters, and large chain retail organizations have imposed. Fiber
producers will not allow the use of their brand names if fabrics do not meet certain specifications. Also, the major
42 EFFECTS OF AIR POLLUTANTS ON TEXTILE FiBERS AND DYES
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mills seem, in essence, to have the technical competence to recognize and evaluate complaints once they have been
established. It should be pointed out, however, that more recent information relative to the fading of dyes on
cotton and rayon and to the discoloration of whites has not yet been fully recognized and dealt with by the textile
industry.
While the major fabric mills strive to produce quality products, some mills and dyehouses do process goods
of lower competitive costs, using dyes and finishes that are vulnerable to air pollutants. They are aware that pol-
lution can cause trouble, but are willing to take the risk that no major problems will develop or, if problems do
develop, that complaints will be scattered and not economically important.
Producers of Apparel, Home Furnishings, and Other Goods
Within a sizable and diverse group of many large and small producers of various types of apparel, upholstered
furniture, carpets, and miscellaneous finished textile goods, a number of trade associations are active, and most of
them are aware of the problems that air pollutants may cause. For example, the American Apparel Manufacturers
Association has recently distributed a bulletin to its members alerting them to potential fading damage by ozone in
some permanent-press fabrics. The National Association of Hosiery Manufacturers has been aware for some time
that acid aerosols may attack nylon stockings and cause runs; they have warned their members of this problem. In
addition, textile testing laboratories, including the Good Housekeeping Guaranty Seal, American Institute of Laun-
dering, U. S. Testing Company, Better Fabrics Testing Bureau, and the American Standards Association (L.22
Standards), have specifications for colorfastness to NO and ozone. These specifications have been recommended
by various trade organizations within the textile industry as levels of performance that meet consumer expectations.
For the most part, the large textile producers, especially those who have stressed quality products and have
developed close ties with fiber and fabric producers, are aware that air pollution may cause problems. Despite the
efforts of trade associations, however, the smaller producers have been slow to develop awareness. This attitude
appears, however, to be changing as concern for the environment gains more public attention.
Consumer-Oriented Groups
Awareness varies widely among the many individuals and organizations dealing directly or indirectly with
consumers, including the various retail chain and department stores, laundry and dry cleaning establishments, and
home economics interests. An early indication of awareness by a retail outlet is gained from Labarthe’s 1 interesting
study. He surveyed over 10,000 complaints submitted by a major department store in Pittsburgh to the Mellon
Institute for analysis during the years 1935 through 1953. All the complaints were divided into two categories:
customer faults and merchandise faults. Customer faults, which made up about two-thirds of all the complaints,
included mainly damage problems that ustomers brought on themselves by misusing the merchandise or failing
to follow label directions. Of the remaining one-third of the complaints (merchandise faults), Labarthe found that
gas fading was one of the most common causes. For example, it caused one-half (193 cases) of all merchandise
faults on women’s acetate dresses.
Labarthe documented for one.chain of retail stores (Table 4-1) the number of customer complaints attributed
to gas fading on women’s dresses made from all the principal fibers. The number of fading complaints is expressed
as a percentage of the total number of registered complaints, including both customer and merchandise faults.
The data reveal that serious problems existed during the 1930’s and mid-1940’s and that subsequent corrective
measures resulted in a significantly reduced number of complaints. Obviously, during these years, this retail store
knew of the effects of air pollution, but this awareness was not typical of similar “non-chain” retail outlets.
The large chain type department stores, such as Sears, Penney’s, and Macy’s, understand the various damage
problems that air pollution can cause. They have established performance specifications that their suppliers must
Industrial and Commercial Awareness 43
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Table 4-1. CUSTOMER COMPLAINTS ABOUT FADING
ON WOMEN’S DRESSES
-1
Time interval, Fading complaints,
yr % of total complaints
1935-41
1942-45
1946—47
1948-49
1950-51
1952-53
8.1
23.8
6.2
5.6
2.8
2.1
meet, and most have quality control laboratories that check incoming merchandise against these specifIcations. In
addition, their suppliers, especially for such items as draperies and home furnishings, have become familiar with the
fading effects of air pollution and have taken remedial steps to reduce such occurrences.
These efforts by the large retail chain stores and their suppliers have resulted in a gradual reduction of con-
sumer complaints in recent years. Currently, these stores report that the complaints about textiles that are traced
to air pollution are relatively few and not considered serious. Even in the past. however, the number of registered
complaints has been fairly low as is apparent from the fact that, of the many retail outlets queried, none had ever
organized their complaint records to show air pollution as a cause. Of course, this evidence does not necessarily
mean that damage from air pollution was insignificant. Consumers have many complaints that go unreported, and
sometimes they are not even aware that damage has occurred, especially in the case of color fading in which the
effect is insidious and often goes undetected until clothes come out of storage or come back from the dry cleaner.
Various trade associations that are consumer-goods oriented are aware that air contaminants can impair textile
goods and have alerted their members by periodically sending out information bulletins. Many retail outlets and
merchants, however, especially the smaller ones, depend on their suppliers to furnish them with quality merchandise.
Apparently, the information supplied in the bulletins is seldom passed on to the sales clerks, who mainly deal with
customers and, in many instances, receive and adjust complaints. As a result, air pollution damage is usually not
suspected of causing complaints.
Dry cleaning and laundering trade associations are also aware that air pollution can damage fabrics. They
have warned their members that various color.fading problems can occur and that consumers may attempt to blame
fading on previous dry cleaning or laundering operations. The National Institute of Dry Cleaning keeps abreast of
the types of problems its members encounter by annually processing a large number of complaints that individual
members submit because they are unable to establish the cause clearly. In 1967, the Institute attributed 727 com-
plaints to gas fading. Medsker 2 compiled information on complaints from files of the Detroit Dry Cleaning and
Laundry Institute and found that atmospheric fume fading was a frequent cause. In 1962, consumers registered
the most complaints in October, November, and December, the months that many garments come out of storage.
Likewise, Pollock 3 found that a majority of dry cleaners and retailers surveyed in a national sample (early 1960’s)
regarded gas fading as a major factor in causing color change.
Home economists also are aware of the damage air pollutants can produce, and some academic groups in this
field have conducted research on air pollution effects. In a study of the signifIcance of consumer textile complaints,
Quinn, 4 a member of the consumer interests committee of the American Home Economics Association, emphasized
that consumers, by registering legitimate complaints, play an important role in helping to develop textile standards.
44 EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
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These standards naturally work to the advantage of consumers since they establish minimum end-use requirements
for a variety of textile fabrics.
CONCLUSIONS
On the basis of information solicited from a wide range of textile interests, awareness of the effects of air
pollutants on textiles and dyes is generally strongest among those parts of the industry farthest removed from con-
tact with the consuming public. Thus, the manufacturers of fibers, dyes, and specialty chemicals are conscious of
the effects of air pollution. Such awareness is found also among most of the fabric producers and dyers.
Manufacturers of apparel and home furnishings and the numerous retailers show a mixed degree of awareness,
with the larger organizations generally more conscious of the problem than the smaller ones. Many of these organi-
zations have quality control laboratories and have issued performance specifications that merchandise from their
suppliers must meet. To various degrees, all within this general group depend on their suppliers to furnish quality
products, especially those suppliers with well-publicized brand-names. The suppliers must concentrate on producing
quality products in order to protect the gains resulting from their brand-name promotional efforts.
Because of the general reluctance of consumers to complain and because awareness at the retail level is weak,
many textile problems caused by air pollution go unreported or unidentified. Since complaints serve an important
function in identifying and establishing problems at the manufacturing level, consumers should be encouraged to
report them. Likewise, the retail trade should alert their sales people to the problems that air pollution can produce
so that they can at least suspect it as a possible cause for complaints. Therefore, in order to establish an accurate
record of the damaging effects of air pollution on textile products, increased awareness, as well as better communi-
cations, must be developed among consumers, retailers, and producers.
REFERENCES FOR CHAPTER 4
1. Labarthe, J. Ten Thousand and One Consumer Complaints. Text. Res. J. 24:328-342, April 1954.
2. Medsker. S. Textile Performance Problems: Their Causes and Recommendations for Solutions. Master’s Thesis,
Wayne State University, Detroit, Mich., 1964.
3. Pollock, F. F. Consumer Problems Related to Color Changes in Textile Products. Master’s Thesis, University of
North Carolina at Greensboro, 1964.
4. Quinn, F. R. Significance of Consumer Textile Complaints, J. Home Econ. 52:253-255, April 1960.
Industrial and Commercial Awareness 45
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CHAPTER 5
CONSUMER AWARENESS*
INTRODUCTION
As noted in previous chapters, researchers have documented considerable evidence on the adverse effects of
air pollution on textile fibers and dyes. They have shown by laboratory tests and service exposure trials that various
problems can be caused by air contaminated with small amounts of one or more of the following: SO 2 , NOR,
ozone; and particles (soiling). As discussed in Chapter 4, however, awareness of the various problems that polluted
air can produce is generally strongest among such interests as fiber and dye producers, which are farthest removed
from the consuming public. In fact, the gap between scientific evidence and public knowledge may be substantial.
In order to arrive at a more positive measure of this gap, Dr. George B. Sproles, a research economist and
member of Dr. Salvin’s staff, conducted a public survey that focused on consumer awareness of the detrimental
effects of air pollution on textile products. This exploratory survey was carried out in Philadelphia, Pennsylvania,
during the winter of 1970. Details and results are reported in this chapter.
The decision to measure consumer awareness of the detrimental effects of air pollution on household textile
products was made oniy after carefully evaluating its overall importance. On the basis of a subjective analysis, con-
sumer awareness of the effects of air pollutants on textiles and dyes was judged to be important because of the
impact it would have on goods and services. Consumers having such awareness are likely to (1) be alert to problems
potentially caused by air pollutants; (2) report to retailers those problems that normally would go unreported, and
thus may receive better adjustments; (3) question the resistance of fibers and dyes to air pollutants and will, there-
fore, indirectly demand better merchandise; and (4) demand a cleaner environment arid thus have political impact.
In the absence of studies that shed liglit on how consumers react to new information about the effects of air
pollution on textiles (awareness), the statements above may be subject to question. Admittedly, consumers are a
variable group, and individuals do handle new information in different ways. Some may immediately dismiss it as
irrelevant and unimportant, while others may make maximum use of it; many will react in a manner somewhere
between these extremes.
Socioeconomic factors strongly influence consumer reaction. For example, where consumers live is most
important; those living in low-pollution areas have little use for effects information, and therefore awareness is not
significant. Effects information could be useful, however, for the majority of the population who congregate in
urban areas where pollution can be severe and problems are more likely to occur. Income is another important
factor. Low income families are more concerned with the day-to-day problems of life, while middle and upper in-
come families are more likely to take notice of textile problems and question the influence of air pollution.
In evaluating the importance of consumer awareness, researchers subjectively took into account all of these
socioeconomic factors. The overall consensus was that consumer awareness was important and that the public
would benefit by becoming more aware of the effects of air pollution on textile products. Furthermore, a measure
of consumer awareness is necessary to assess the need for public information programs and to make improved
estimates of economic losses.
*The information presented in this chapter is taken from a paper entitled, Public Awareness of Air Pollution Damage to Textile
Products: A Survey of 1-lomemakers, by George B. Sproles, who is currently on the faculty of Purdue University.
47
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BACKGROUND
To gain background information for planning, designing, and analyzing the Philadelphia survey, the investiga-
torS reviewed and examined several important issues. They considered: (1) public awareness as it relates to air
pollution in general, (2) the dissemination and public awareness of information on air pollution damage to textiles,
(3) the unique characteristics of textile products, (4) the influence of socioeconomic factors on public awareness of
air pollution, and (5) various survey research techniques available for assessing consumer experiences with air pollu-
tion.
Public Awareness of Air Pollution
Air pollution publicity in recent years virtually ensures public awareness of this environmental problem,
particularly in urban areas, where active regional newspapers and pollution control organizations have supplemented
the efforts of the national media. Emphasized in recent Presidential State-of-the-Union messages, pollution con-
trol has become a political issue of national significance. College students and environmental activists have shifted
their attention to ecology and the preservation of the environment. Trends clearly indicate an increase in public
awareness of environmental problems.
While pollution control may have only recently received widespread public attention, the issues and questions
related to air pollution have been acknowledged for many years. Federal agencies have conducted extensive
research and publicity programs, and recognized authorities on the economic, political, and technological problems
of air pollution control have published their views and findings. At least one comprehensive synthesis of economic
theory and research findings has been publicized, the work of Ridker, 1 in which he discussed the costs of air poi-
lution damage and the frustrating difficulties that beset investigators in this area.
Several recent public-attitude surveys are of specific interest in the assessment of consumer experiences with
air pollution effects on textiles. Unfortunately, no survey has focused strictly on air pollution damage to textiles,
although a few have attempted to isolate the cleaning costs associated with soiling. Public information and educa-
tion concerning air pollution effects on textiles is also scarce. Research findings, therefore, have been informative
only with respect to the general aspects of the air pollution problem.
De Groot 2 has reviewed a series of surveys on public air pollution awareness that were conducted primarily
in the early 1960’s, well in advance of current air pollution publicity. In each survey, a consistently large number
of respondents considered air pollution a problem in their locality. Generally, the proportion of respondents view-
ing air pollution as a problem increased as the level of air pollution in their community increased. Health problems
were by far the greatest reason for air pollution concern. Interestingly, the respondents tended to perceive air
pollution as a less severe problem in their own neighborhood than in the entire community. As De Groot suggests,
a denial mechanism may be at work, for it may be psychologically demanding for people to admit to a larger prob-
lent in their neighborhood than in the community as a whole.
Undoubtedly, socioeconomic factors influence public attitudes toward air pollution. In the surveys De Groot
reviewed, however, the level of air pollution was found to have more influence on attitudes than home ownership,
family size, age, sex, race, and income. In a more recent survey of public attitude in Johnstown, Pennsylvania,
Crowe found various socioeconomic factors to be associated with the public perception of air pollution. With in-
eteases in education and income, respondents defined air pollution more in terms of sources than effects. The
degree of sophistication of the air pollution defmition also increased with education and income. Length of resi-
dence, sex, and to a lesser extent, place of residence were not particularly associated with air pollution perceptions.
Though public concern about air pollution is growing, Rankin 4 presents some evidence that indicates public
disillusionment, disinterest, or apathy toward the prospects of control and abatement. In a survey of the attitudes
of residents in Charleston, West Virginia, and three neighboring communities, respondents in all communities were
apóreciably aware of air pollution and were optimistic that it could be substantially reduced. More than half of the
48 EFFECIS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
-------
respondents in each community, however, expected air pollution to remain the same or become worse over the next
5 years. More than two-thirds of the respondents were either unaware or uninformed of current governmental con-
trol programs, both at the national and local levels. Such lack of knowledge is certainly conducive so disillusionment
and apathy in many segments of the population.
Closely related to public apathy concerning air pollution may be the question of priorities for solving a
variety of contemporary urban problems. Issues such as education, race relations, urban renewal, mass transporta-
tion, crime, and pollution compete for public attention. Apathy toward pollution may be another way of express.
ing concern for more important problems. In several of the previously mentioned surveys, public perceptions of the
importance of air pollution were examined in relation to other urban problems. In all four West Virginia communi-
ties surveyed by Rankin, the air pollution problem received a greater percentage of “very serious” or “somewhat
serious” ratings than did problems concerning lack of recreational facilities, unemployment, race relations, juvenile
delinquency, traffic, and low-income medical care. In the Johnstown, Pennsylvania, survey, however, Crowe
found that problems of unemployment, traffic, and lack of recreational facilities ranked above air pollution in
importance, although in the absolute sense air pollution was nevertheless considered an important problem. The
overall results of D c Groot’s review were similar to those of Crowe; in several of the surveys, however, air pollution
was recognized as a greater problem than other typical urban problems.
These surveys show that the public is well aware of the air pollution problem and rates it among the most
serious of urban concerns. The public also understands that air pollution is unhealthy. Problems of personal
property damage have not, however, been widely publicized. Some apathy concerning air pollution control and
abatement has developed, partially resulting from the low level of public knowledge about local and national con-
trol programs.
Public Information About Air Pollution Effects on Textiles
A survey of popular national mass news media, including weekly news magazines, showed that the overall air
pollution problem has received extensive publicity during the past several years. The media have hardly mentioned
damage to textile products, however, except for occasional publicity given to infrequent episodes of air-pollution-
induced runs in women’s nylon hosiery. This lack of information for public consumption is not surprising because,
in the past, knowledge of air pollution effects on textiles has not spread to any great degree beyond the confines of
the textile industry. Today, however, expansion of this knowledge and understanding seems to be taking place.
Home economists and other consumer scientists are the current leaders in consumer education with respect
to textile problems. Textbooks widely used in home economics education specifically discuss air pollution effects
on textiles, with emphasis on gas fading of dyed acetate fabrics. Air-pollution-induced soiling and fabric deteriora-
tion, however, receive little attention. Unfortunately, home economics education does not reach all segments of
the population, and the dissemination of information is therefore limited.
Among textile and apparel manufacturers, air-pollution effects are well-known. Test standards for defects
caused by weathering and certain air pollutants have been established for many years. Although standards for air
pollution resistance are included in many programs for product quality testing, information is not ordinarily
disseminated to the general public. Occasionally, however, resistance to gas fading has been mentioned on textile
product labels. This problem has also been briefly covered in some promotional and educational literature. Such
point-of-purchase information will likely increase in the coming years as manufacturers take further interest in
consumer education as a promotional strategy. For the present, manufacturers continue to press more for technical
improvements in developing fibers and dyes that resist air pollution.
Characteristics of Textile Products
Clothing and home furnishings, while necessities of life, are influenced considerably by fashion. Style
obsolescence often dictates the disuse of textile products long before physical wear life has been expended. Although
Consumer Awareness 49
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air pollution effects may result from exposures as short as 1 to 3 months, more typically they will take 1 or more
years to become noticeable. Often, these effects are so gradual as to go totally unnoticed. Also, some textile prod.
ucts, primarily clothing, may be only infrequently exposed to air pollution so that they may be discarded for
fashion reasons long before air pollution effects can occur or become apparent.
The difficulty in determining air pollution effects on textiles is complicated by other damage mechanisms.
Sunlight, laundering, mildew, abrasion, and other damage causes may be more important than the effects of air
pollution. Furthermore, air pollutants may combine with these other causes to produce synergistic effects.
Consequently, it is often impossible to identify the single most important cause of damage.
Social and Cultural Influences
Surveys discussed earlier show that socioeconomic and cultural factors influence air pollution awareness and
attitudes. In a society of ever-increasing affluence, many individuals may perceive little economic consequence
from problems caused by air pollution. This lack of perception may be the case especially where textile products
are concerned, since style obsolescence and other types of problems may have more economic importance than
problems caused by air pollution.
The income factor may have real significance in public reactions to the costs of soiling resulting from air poi-
lution. Furthermore, standards of cleanliness may vary with the ability to pay for extra cleaning. Closely related
to standards of cleanliness are social class and cultural factors. In more affluent classes, it is both economically
feasible and socially necessary to maintain a high level of cleanliness. Thus, additional cleaning costs become a
necessary burden of some social classes, although it is a burden that falls on those who can most likely afford it.
In other social and income classes, however, individuals may learn to live with increased soiling because of lower
standards of cleanliness or reduced ability to absorb the extra costs, or a combination of these reasons.
Another factor affecting the importance people attach to air pollution is that air pollution competes with
many other social problems for public attention. Accordingly, the importance of pollution control is frequently
overshadowed by social problems such as urban renewal, education, welfare, methcal care for the indigent, crime,
and drug control. Furthermore, textile problems resulting from air pollution must compete with more widely
recognized air pollution problems such as health effects, reduced visibility, and malodors. In this competition,
damage to material products may, therefore, be considered less important than these other significant problems.
These other air pollution problems generally take precedence over materials effects problems, especially textile
effects.
Survey Research Techniques
Several research techniques may be useful in assessing consumer experiences with air pollution. Public opinion
surveys have been the most popular method. Also, for some research questions, useful data on consumer complaints
and problems may be obtained from records of retail stores, corporations, cleaning establishments, and trade
associations, and from consumers’ expenditure records. When available in useful form, the latter sources may be
especially valuable for economic analysis. Store or corporate complaint records, however, may be of only limited
use because consumers are often reluctant to register complaints even in valid cases. Consumer surveys, therefore,
seem to be the most productive means of acquiring information for assessing the extent and magnitude of problems
related to air pollution.
In public opinion research, the major problem is to design a questionnaire that validly measures the variables
under study. Questionnaires are research instruments that, if properly developed and applied, yield scores or
measures of variables that have been found to be reliable and empirically valid. Determining the appropriate
variables to measure is particularly difficult in exploratory investigations. Survey researchers must design questions
that the public can respond to effectively and without confusion. A number of problems come into play such as
50 EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS Ar4D DYES
-------
respondent or interviewer bias, overreporting bias, respondent fatigue or disinterest, poor recall or memory, and a
host of other influences surrounding the interviewing situation. In theory, these biasing influences may be controlled
by the use of a well-designed survey plan and of qualified interviewers. As a result, public opinion research can often
yield a significant degree of statistical precision when compared to other data collection methods.
ThE PHILADELPHIA SURVEY PLAN
Objectives
The primary objectives of this survey were:
1. To measure consumer awareness of the detrimental effects of air pollution on household textile products.
2. To evaluate the overall importance of household textile problems caused or potentially caused by air
pollution.
Several supplementary objectives were:
1. To measure public awareness of air pollution and its associated problems.
2. To evaluate the influence of socioeconomic factors on consumer attitudes and awareness.
3. To measure the dissemination and availability of public information on the effects of air pollution on
textile products.
Approach
Although laboratory research and field service trials have shown that air pollution affects textile products, no
systematically documented evidence of actual consumer experiences had been collected prior to the Philadelphia
survey. This project, therefore, focused on identifying textile problems that consumers directly associate with air
pollution, though at the outset, the investigators realized that consumers, in many cases, would not recognize this
association. Therefore, in an attempt to overcome this lack of recognition, the survey included questions on
selected textile problems that previous scientific research had shown to be caused by air pollution.
Methodology for the Philadelphia survey differed somewhat from previous surveys that sought information on
air pollution damage to materials. The earlier surveys assumed that damage problems were recognizable and pro-
ceeded directly to question the respondents on the frequency of occurrence, frequency of cleaning or maintenance,
etc. Such information is particularly useful for direct economic analysis if the assumption is valid that individuals
recognized the problems and could recall bow frequently they experienced them. The direct approach, however,
may not be-feasible because individuals surveyed may not accurately recall the necessary frequencies. On the basis
of these considerations, the Philadelphia survey concentrated on identifying problems rather than measuring fre-
quencies of occurrence. This research strategy may not lead to direct economic analysis of air pollution problems,
but it does provide a more acceptable test for the actual occurrence or nonoccurrence of specific problems. In
addition, the methodology may usefully identify problems not previously considered, thus suggesting directions for
future scientific investigations.
Survey Methodology
Several key considerations entered into the decision to conduct the survey in Philadelphia. Of special interest
was the fact that the city had been the scene of several important government-sponsored air poliution studies,
including a recent survey to estimate residential soiling costs. 5 Philadelphia also has an active air pollution control
program. A rather comprehensive data bank had, therefore, been generated for this city, enabling useful
Consumer Awareness 51
-------
comparisons among the various studies. A further consideration was that Philadelphia has one of the most severe air
pollution problems in the United States. Significant air pollutants include particulate matter, oxides of sulfur, and
hydrocarbons. Though no “ideal” city exists where high levels of all potentially damaging pollutants are found,
Philadelphia is among the highest in nearly all pollutants with the exception of oxidants. Nevertheless, oxidants
are present at levels that can cause textile problems.
The investigators determined that a sample size of 400 would give reasonable statistical accuracy for the sur-
vey. They randomly selected the sample from the 1969 Philadelphia County telephone directory, the most
accurate listing of households available. Since a certain lack of response was anticipated, an initial sample of 600
respondents was selected. As the survey progressed, it became necessary to increase the sample by 400 in order to
complete 400 interviews.
For later data analysis, the investigators divided the sample into two geographical areas, based on air pollution
levels. Published air pollution concentration maps 6 were used for this purpose. Although these maps were not
highly detailed, it was apparent that lower levels of pollution existed in the northwest and northeast sections of the
city, while higher levels prevailed in the center city area. According to their place of residence, respondents were,
therefore, classified either as living in “high” or in “medium to low” pollution areas.
Analysis of 1960 census data 7 indicated considerable socioeconomic differences between the two “pollution”
areas of Philadelphia. Residents in the northeast and northwest subruban sections of the city were largely white
collar workers of higher income, while those in the center city area were mostly lower-income blue-collar workers.
The socioeconomic differences between the two areas may have a potentially biasing effect on area-by-area air
pollution awareness and attitudes. Such possibilities will be examined.
All interviews were conducted by telephone, one of the most economical methods of collecting data and
quite adequate for exploratory surveys. Although telephone interviewing limits the complexity of questionnaire
design and measurement techniques, a pretest of the questionnaire indicated that useful data could be obtained
by this method. The use of self-administered mail questionnaires was not considered because of greater expense
and typically low response rates.
Questionnaire Design
The initial survey questionnaire was designed using questions similar to those included in previous air pollu-
tion public-opinion research. Several questions focusing on the general problem of air pollution were specifically
basedonpreviousresearch. They were included in the first part of the questionnaire, followed by questions seeking
general information on clothing and home furnishings problems that respondents may have recently experienced
without regard to possible air pollution relationships. Subsequent questions concentrated directly on the association
between air pollution and textile damage. Concluding questions furnished basic demographic data.
After pretesting, the questionnaire was modified to the final form presented in Appendix A. (Pretesting sug-
gested the rewording of several questions, and a few questions were either reordered or discarded to allow a smoother
sequence of questions.) The questions fall into four specific groups:
1. General air pollution awareness and attitudes (questions 3,6,7, and 8).
2. Experiences with various clothing and home furnishings problems, without specific consideration of
air pollution effects (questions 4, 5, 13, and 14).
3. Knowledge and opinions on the association between air pollution and textile damage (questions 9, 10,
11, 12, and 15).
4. Socioeconomic and related information (questions 1,2, and 16 through 21).
l’he fmal questionnaire represented a trade-off between comprehensive coverage of research issues and the need to
limit questioning within the constraints of telephone interviews.
52 EFFECFS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
-------
Field Administration
The survey was administered by long-distance telephone during a 1-month period in February and March
1970. Interviewers were given special training and experience prior to their conducting the survey. All interviewers
possessed technical knowledge of air pollution effects on textiles. This background proved useful in identifying
potential air pollution problems for further discussion with respondents; interviewers who were less competent
technically might easily have overlooked textile problems that, in fact, could be associated with air pollution.
Interviewers made four attempts to reach each household, including evening “cailbacks” to those households
that did not answer during the daytime.They talked only to the female homemaker in each residence; homes unable
to meet this condition were discarded from the survey. The approach of interviewing only female homemakers was
based on the knowledge that women are the major consumers of textiles, both for themselves and for other family
members. As “family purchasing agents,” they are most likely to be both well informed of and experienced with
textile problems.
The interview completion rate for the survey (Table 5-1) was not as high as had been expected. Completed in-
terviews were obtained from only 42 percent of the initial 600 households called. A secondary sample of 400
respondents was then generated in order to complete the survey sample. Of the secondary sample, 391 respondents
were called at least once in order to complete the 400 interviews desired. The overall survey response rate was 41
percent. It is noteworthy that 15 percent of the sample was disqualified because the numbers called were business
phones, phones were not in service, or no female was in residence; and that 7 percent of the respondents did not
provide information because of sickness, old age, or other valid reasons. if these negative responses are removed
from the analysis, the survey response rate is well over 50 percent for the entire sample.
It should be pointed out that some lower income families do not have telephones and that a number of
people, especially among the upper income and professional occupation classes, have unlisted numbers. Thus,
sampling from a directory implies a bias in selection of income and occupation extremes in the population. The
survey results, therefore, have a degree of nonresponse bias, the direction and extent of which are unknown.
Table 5-1. SAMPLE RESPONSE RATE
(percent)
Results of attempts to call
Initial sample
(n = 600)
Total sample
(n = 991)
Complete
Refused
Legitimate refusals
Not contacted
Business phones
No female in residence
Phones not in service
42
25
8
9
4
6
6
41
23
7
14
4
6
5
THE PHiLADELPHIA SURVEY FINDINGS
Profile of Survey Sample
Tables 5-2 through 5-6 summarize the collected data, and Tables 5-7 through 5-13 test for relationships among
various relevant variables through cross-classification analysis. For all tables, columns for individual topics may not
Consumer Awareness 53
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always total 100 percent because (1) rounding-off errors may be involved; (2) multiple open-end responses were
collected; or (3) less than the total sample was required to respond.
Table 5-2 presents a profile of the socioeconomic and related characteristics of the survey sample. All
socioeconomic classes were well represented in the sample, and the distributions corresponded closely to national
and urban averages for the population characteristics. The table if further broken down into “Area 1,” the
higher air pollution center-city area, and “Area 2,” the lower air pollution suburban area. Clear socioeconomic
differences existed between the two areas, primarily in education and income and, to a lesser extent, age.
Socioeconomic differences between the two areas reflect the well-known migration of white collar workers from
the center city to the less congested and less polluted suburban areas. The observed differences between the areas
were generally in accord with those expected from 1960 census data and population projections.
Analysis of Responses Related to Air Pollution Factors
Table 5-3 summarizes several measures of various air pollution factors included in the survey. The first part
of the table focuses on general air pollution awareness and attitudes, while the latter part examines specific public
perceptions of the association between air pollution and textile problems. The general questions were similar to
those used in previous public opinion investigations, and the fmdings were also quite similar. Questions concen-
trating specifically on air pollution textile problems were unique in this survey.
Analysis of Table 5-3 indicates considerable public awareness and concern with the overall air pollution prob-
lem. When asked the open-ended question of what problems were associated with living in Philadelphia, the two
most frequently mentioned were air pollution and crime. Dirtiness of the city, which is air pollution associated,
was also mentioned. Only 15 percent of the respondents actually mentioned air pollution (second only to crime,
at 16 percent), but it is important that this problem was among those most frequently mentioned. About one-half
of the respondents did not mention any problems.
Respondents conceptualized the air pollution problem largely in terms of transportation (auto and diesel
exhausts) and industrial sources and, to a slightly lesser extent, in terms of health problems, smoke and soot, and
odors. Thus, the concepts were primarily related to visible effects and odors. Only a few respondents mentioned
the important gaseous pollutants such as oxides of sulfur and nitrogen. Not a single respondent mentioned effects
on materials as a result of air pollution, even though soiling is a major visible effect. Furthermore, 22 percent of
the respondents had no specific air pollution conceptualization. This figure may be a measure of air pollution
nonawareness and, as such, may imply that more people are truly unaware of air pollution than previous analyses
indicated. Overall,however, 65 percent of the respondents perceived air pollution to be a “very serious” problem in
their community.
When asked if they had ever experienced problems with air pollution (not to be confused with respondents’
concepts of air pollution), 46 percent of the respondents replied in the affirmative. Health and odor problems were
most frequently mentioned; 4 percent of the respondents mentioned textile problems. When specifically asked,
however, if they had noticed textile problems thought to be caused by air pollution, 15 percent of the respondents
said they had experienced such problems. General soiling and, to a much lesser extent, specific drapery problems
(color change, soiling, and deterioration) were mentioned. Also, 28 percent of the respondents perceived that the
cost of textile problems caused by air pollution was at least “somewhat serious.” When asked why they considered
the costs “serious,” respondents mentioned a combination of laundering, deterioration, and clothing-appearance
problems.
The survey indicates, therefore, that only a small segment of the population was aware of the textile problems
caused by air pollution. Soiling was the most obvious problem; color changes and fabric deterioration received
scattered mention. Apparently the relationship between air pollution and the major textile problems caused by
pollution was neither well conceptualized nor well understood by the respondents. Furthermore, compared to gen-
eral public awareness of air pollution, awareness of air pollution effects on textiles was minimal.
54 EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
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SOCIOECONOMIC PROFILE
(percent)
Area 1
(higher air
pollution)
(fl= 168 )a I
Residence time
in Phi1adelt hia
10 years
> 10 years
Residence time
in present home
< 5 years 31
5 to 10 years 17
> 10 years 52
Number of people
living in home
lor2 34
3to5 51
6 or more 13
No answer 2
Age of respondent
18to29 21 21
30to39 25 27
40to49 20 23
50to59 14 15
60 and over 20 11
Refused to answer 0 3
Education of respondent
31 18
42 39
16 25
10 17
1 1
$6,000 24 14
$6,000 to $9,999 24 24
$10,000 to $14,999 25 26
$15,000 9 20
efused to answer 7 9
Not known 10 7
Type cf heat
Electric 7
Gas 48
Oil 29
Other 17
Air conditioners in home
Yes
No
No answer
Table 5-2.
OF SURVEY SAMPLE
Socioeconomic factors
Area 2
(lower air
pollution)
(n=229)
Total
sample
(n=400) a
18
82
19
81
33
23
45
29
49
18
3
Non-high school graduate
High school graduate
Some college
College graduate
No answer
Total annual family income
19
81
32
19
49
32
50
15
2
21
26
21
14
16
2
25
41
20
13
20
24
25
14
-8
9
8
52
26
13
61
38
1
10
60
23
8
71
28
1
54
46
aThree respondents could not be classified into either Area
their place of residence could not be located.
1 or Area 2 because
Consumer Awareness
55
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U,
a.’
Problems with living In the Philadelphia area
Air pollution
Crime
Poor schools
Traffic and congestion
Noise
Poor recreation
No specific problems (likes Philadelphia)
Other (dirty city, ghettos, poor shopping,
racial problems, etc.)
Respondent concepts of air pollution
Auto and diesel exhausts
Industrial wastes
Health problems
Odors
Dirt and dust
Smoke and soot
Haze or fog
Materials damage
Other (nothing specific)
Perceived seriousness of air pollution
problems in respondents’ comunities
Very serious
Somewhat serious
Not serious
Do not know
Respondents reporting problems specifically
caused by air pollution
Yes
No
aAll percentages are based on the entire sample Of
Types of air pollution problems mentioned
Health problems or irritations
Odor problems
Textile damage
Other materials damage
Dirtiness in general; other
Respondents reporting textile problems that they
thought were caused by air pollution
Yes
No
Not sure
Types of textile problems associated with air
pollution
General soiling
Drapery yellowing
Drapery color losses
Drapery soiling by soot
Drapery rotting
Other (fabric deterioration, outdoor furniture
damage, extra clothing soiling, carpet soiling)
Perceived seriousness of economic costs of textile
problems caused by air pollution
Very serious
Somewhat serious
Not serious
Do not know
Reasons mentio? ed for serious costs of textile
problems caused by air pollution
Increased laundering
Faster clothfttg deterioration
Poor appearance of clothing
Other
Table 5-3.
ANALYSIS OF RESPONSES RELATED TO AIR POLLUTION FACTORS
(percent)
Urban and air pollution problems
Responsea
Urban and air pollution problems
Responsea
15
16
6
9
5
2
51
31
42
32
32
25
20
32
8
0
22
65
21
10
4
46
54
29
18
4
4
8
15
75
10
10
1
2
1
1
7
21
60
13
17
14
11
1
400 respondents.
-------
Specific Clothing and Home Furnishings Problems
Early in the survey interview, each respondent was asked an open-ended question on various textile problems
she hadexperiencedin the past year. Responses are summarized in Table 5-4. A total of 34 percent of the respond-
ents mentioned clothing problems, and 26 percent, home furnishings problems. Possibly more problems would
have been mentioned in a structured interview, but open-ended questions were used to collect data on problems
that would be important enough for respondents to recall immediately. Probably more textile problems exist than
were documented in the survey, but it is noteworthy that nearly every currently important textile problem was
mentioned by at least a few respondents.
For the most part, respondents tended to mention general clothing problems rather than experiences with
specific items. A useful analysis of the colors, fibers, and causes of various clothing problems mentioned was not
possible. In the absence of specific questions suggesting a possible cause-effect relationship, it is important to note
that respondents did not associate air pollution with most of the difficulties mentioned; in fact, most of the p rob-
lems mentioned are not normally associated with air pollution. The few clothing problems mentioned that could
have been caused by air pollution were soiling, color changes and fading, and loss in useful life of nylon hosiery.
Respondents gave no substantial evidence for relating air pollution to these problems, however.
Home furnishings problems were different in this respect since many appeared to be associated with air pol-
- lution, both in the type of problem mentioned and in the opinions of some respondents. Furthermore, the colors
and fibers most frequently mentioned were those most susceptible to air pollution.
In designing the survey, the investigators anticipated that respondents would have trouble recalling many
textile problems and, consequently, included inquiries about typical textile problems potentially caused by air
pollution. Results of this analysis appear in Table 5-5. Five of the six problems surveyed involved fabric color
changes, and the table includes specific colors mentioned. About one-half of all respondents said they had noticed
color changes in clothing linings and in clothing that had been stored in closets. The response to the other color-
change inquiries ranged from 17 to 36 percent. The largest percentage of respondents recalled specific color change
problems occurring during storage. The most frequently mentioned color was blue;many blue dyes are known to
be sensitive to air pollution. Blacks and purples were the next most frequently mentioned colors. Reds, greens,
yellows, and browns received Scant mention.
Hosiery damage was harder to assess. Given the numerous causes of hosiery damage, it is difficult to
determine what constitutes an “abnormal” problem. Thirty-three percent of the respondents thought that they
had regularly experienced unexplainable problems, however; several directly implicated air pollution.
Respondents were also asked if they had complained to retail stores about any of their textile problems. The
results of this analysis are uniformly negative and are only briefly summarized. A total of 27 percent reported
complaints other than style or fit adjustments. Complaints related largely to construction or premature fabric wear
and, to a lesser extent, to colorfastness. Only one complaint, a Curtain fading problem, seemed to be associated with
air pollution. These results appear suspect, however, since retailers report that only about 1 percent of sold goods
is returned annually. The large percentage of complaints by respondents may have resulted from the fact that they
were allowed to report all complaints that they could recall, not just those of the past year. Also, retailers may
not keep accurate records that reflect actual incidences of complaints. Nevertheless, some overreporting is sus-
pected in this survey.
Consumer Information Sources
Table 5-6 summarizes consumer information sources and knowledge of air pollution effects on textiles. Only
12 percent of the respondents reported having received information about this subject. Most frequently mentioned
sources were newspapers, magazines, and interpersonal communications. The type of information that respondents
Consumer Awareness 57
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Table 5-4. SUMMARY OF TEXTILE PROBLEMS DOCUMENTED IN THE SURVEY
(percent) _______ ____ ___________
Problem documented Responsea
Type of clothing problem (34% response)
Poor general quality or wearing of garments 8
Seam ripping or construction problem 4
Durable press problem 6
Synthetic fibers problem 2
Soiling of synthetics 3
General soiling 3
Dimensional stability 2
Detergent problem 2
Washfastness of dyes 2
General colorfastness 5
Poor fabrics in boy’s pants 4
Yellowing or greying problems 3
Nylon stockings do not last 1
Other (bonding, pilling, frosting, fabric 5
rotting, knit shrinkage, clothing wears
out fast in washing, etc.)
Type of home furnishings problem (26% response)
Drapery color losses 9
Drapery soiling 5
Drapery rotting 2
Carpet soiling 2
Carpet color loss 5
Fading of furniture materials 2
Fading of blanket binding I
Yellowing of drapes 2
Other (carpet wearing out, upholstery 4
problems, general soiling, pilling,
blanket wear, etc.)
Colors and fibers mentioned in connection
with home furnishings
Blue 3
Red 1
Purple or black I
Green or avocado 3
Brown or beige 3
Acetate or rayon 1
Cotton 1
WooI I
Nylon 6
Other synthetic fibers 1
Causes mentioned for home furnishings
problems
Soiling from soot or other air pollution 3
Fading from sunlight 3
Washing or detergent problems 1
Other I____________________
aAll percentages are based on the entire sample of 400 respondents.
58 EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
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Table 5-5. RESPONDENTS EXPERIENCING SELECTED TEXTILE PROBLEMS
POTENTIALLY CAUSED BY AIR pOLLUTIONa
(percent)
Survey responses
Color
changes in
clothing
stored
in closets
Color
changes
in
clothing
linings
Color
changes
in items
made of
acetate
Color
changes
in
carpets
Color changes
in curtains
where
not exposed
to sunlight
Abnormal
nylon
hose
damage
Problems encountered
Yes
No
Colors mentioned
Blues
Purples or blacks
Yellowing or grey-
ing of whites
Greens or avocados
Reds or golds
Browns or beige
49
51
18
9
2
3
1
1
53
47
15
4
1
3
1
2
36
64
4
0
2
1
0
0
17
83
1
1
0
2
1
1
23
77
1
0
2
1
1
0
33
67
—
-
-
-
-
-
aAll percentages are Dased on the entire sample of 400 respondents.
received dealt mainly with fabric soiling and deterioration. The survey also showed that most respondents believed
the public to be generally uniformed about the effects of air pollution on textiles. In view of the often subtle
nature of the textile problems caused by air pollution, however, consumers are not likely to recognize all such prob-
lems and to learn from this recognition. Educational programs will be needed to fill this knowledge gap.
Cross-Classification Comparisons of Areas I and 2
Table 5-7 presents cross-classifications between Area 1 (higher pollution) and Area 2 (lower pollution) for four
measures of general air pollution awareness. Differences in air pollution awareness between Areas 1 and 2 were
minimal. More Area 1 residents, however, mentioned various other problems, such as crime and noise that they
associated with living in Philadelphia. This result was generally expected since Area 1 respondents live in the center
city, where more problems exist. The respondents’ concepts of air pollution were similar in both areas, except that
residents of Area 2 were more likely to mention specific transportation and industrial sources of air pollution.
Virtually no differences were found between the two areas in either perceived seriousness of air pollution or
experiences with problems specifically caused by air pollution.
As to textile problems, the survey detected only slight differences between Areas I and 2; Table 5-8 sum-
marizes five cross-classifications. Area-i respondents tended to report more general textile problems, but those in
Area 2 were a little more likely to associate air pollution with some of their textile problems. The differences, how-
ever, are not significant statistically. Respondents in both areas, therefore, seemed to experience textile problems
to about the same extent. Socioeconomic factors may have influenced these findings.
Consumer Awareness
59
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Table 5-6. CONSUMER KNOWLEDGE OF AIR POLLUTION EFFECTS
ON TEXTILES AND SOURCES OF INFORMATION
(percent)
Consumer knowledge or source
Responsesa
Information received on the effects of
air pollution on textiles
Yes 12
No 88
Sources of information
TV 1
Radio 1
Newspaper 5
1lagazlne 2
Personal source 2
Do not recall 3
Kind of information received
Fabrics wear out 3
Fabrics soil 5
Colors change 1
Nylon hose damage 1
Do not recall 5
Respondents’ perception of what public
knows about effects of air pollution
on textiles
Quite a bit 1
Moderate amount 7
Notmuch 83
Do not know 9
aAll percentages are based on the entire sample of 400
respondents.
Socioeconomic Analysis of Air Pollution Factors
The final part of the survey examined the relationships between various socioeconomic factors and air pollu-
tion awareness and experiences. As suggested by previous investigations, socioeconomic characteristics are likely
to be closely associated with attitudes. In Tables 5-9 through 5-13, various socioeconomic factors are cross-
classified against selected air pollution and textile measures. The socioeconomic factors investigated included
60 EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
-------
Table 5-7. ANALYSIS OF AIR POLLUTION FACTORS: COMPARISON OF AREAS 1 AND 2
(percent)
Area 1
Area 2
(higher air
(lower air
General urban or air pollution factors
pollution)
(n=l68)
pollution)
(n=229)
Problems with living in the Philadelphia area
Air pollution 15 14
Crime 20 12
Poor schools 7 5
Traffic and congestion 10 8
Noise 7 2
Poor recreation 3 1
No specific problem 45 58
Other 37 24
Respondent identification of air pollution
Auto and diesel exhausts 39 46
Industrial wastes 31 35
Health problems 31 32
Odors 25 26
Dirt and dust 20 20
Smoke and soot 31 32
Haze or fog 6 10
Materials damage 0 0
Other 22 21
Perceived seriousness of the air pollution problem in
respondents’ comu ities
Very serious 65 65
Somewhat serious 21 21
Not serious 8 13
Do not know 6 1
Occurrence of problems specifically caused by air pollution
Yes 46 46
No ______ 54 54
aExample interpretation: 15 percent of the 229 Area-i respondents mentioned air pollu-
tion as a problem of living in Philadelphia, while 14 percent of the Area-2 respondents
mentioned air pollution. Columns may add up to more than 100 percent because of the
large amount of multiple responses.
Consumer Awareness 61
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Table 5-8. ANALYSIS OF TEXTILE PROBLEMS: COMPARISON OF AREAS 1 AND 2
(percent)
Problem classification
Area 1 (higher
air pollution)
(n= 168)
Area 2 (lower
air pollution)
(n=229)
Respondents reporting general
clothing problems
Yes 36 31
No 64 69
Respondents reporting general
home furnishings problems
Yes 28 25
No 72 75
Respondents reporting textile
problems that they thought
were caused by air pollution
Yes 14 16
No 75 76
Not sure 11 8
Perceived seriousness of economic
costs of textile problems
caused by air pollution
Very serious 5 9
Somewhat serious 23 18
Not serious 59 62
Do not know 13 11
Respondents experiencing color
changes of clothing stored in
closets
Yes 52 44
No 48 56
Colors mentioned:
Blues 19 17
Purples or blacks 10 6
Whites (yellowing or 3 2
greying)
Greens or avocados 3 2
Reds or golds 1 1
Browns or beige 1 1
62
EFFECFS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
-------
Table 5-9. RELATIONSHIPS BETWEEN EDUCATION AND SELECTED
AIR POLLUTION AND TEXTILE MEASURES
(percent)
Non-hiqh
school
Hiqh
school
At least
some
Air pollution and textile measures/responses
graduate
(n=103)
graduate
(n=164)
college
(n l28)
Respondent concepts of air pollution
Auto and diesel exhausts 30 41 52
Industrial wastes 21 30 45
Health problems 22 30 41
Odors 18 30 26
Dirt and dust 17 14 29
Smoke and soot 24 35 34
Haze or fog 5 10 8
Other 34 19 16
Occurrence of problems specifically caused by air
pollution
Yes 30 45 62
No 70 55 38
Occurrence of general clothing problems I
Yes 31 33 39
No 69 67 61
Occurrence of general home furnishings problems
Yes 22 24 32
No 78 76 68
Occurrence of textile problems thought to be
caused by air pollution
Yes 7 15 23
No 83 75 67
Not sure 10 10 10
Occurrence of color changes of clothing stored in
closets
Yes 48 52 45
No 52 48 55
Colors mentioned:
Blues 19 24 11
Purples or blacks 9 9 8
Whites (yellowing or greying) 2 2 3
Greens or avocados 6 2 1
Reds or golds 1 1 1
Browns or beige 1 2 0
Perceived seriousness of economic costs of textile
problems caused by air pollution
Very serious 9 4
Somewhat serious 14 22 24
Not serious 56 63 59
Do not know 21 11 8
Consumer Awareness 63
-------
length of residence, number of people living in a home, age and education of respondent, and family income.
Seven key measures of air pollution awareness and textile problems were investigated in detail. The overall
analysis reveals some interesting relationships that support the hypothesis that socioeconomic factors may influence
air pollution awareness and attitudes.
Education and Income
Of all the socioeconomic factors involved, education and income were most closely related to selected air
pollution and textile measures. Table 5-9 clearly reveals that with increased education respondents showed in-
creased awareness of air pollution concepts and problems. This was also true for general clothing and home
furnishings problems, and for textile problems thought to be caused by air pollution. The survey found no such
relation, however, between education and observed color change of clothing during storage or between education
and the perceived seriousness of economic costs of textile problems caused by air pollution.
Income Analysis (Table 5-10) tends to support the findings of the education analysis. Respondents in the
higher income category were far more aware of both air pollution and textile problems than those of lower income.
As far as the problem of clothing changing color during storage was concerned, however, both income groups
showed about the same response, although the lower income group was slightly more responsive in naming
specific colors that faded. When questioned about the economic costs of the effects of air pollution on textiles, the
lower income respondents tended to perceive the costs as more serious, although the relationship is minimal. In
general the results of income and education analysis suggest that these factors may be the most significant predictors
for analyzing public experiences with air pollution problems.
Age
Analysis of the influence of age, shown in Table 5.11, revealed interesting relationships. Respondents were
placed into one of three age groups: 18 to 29 years, 30 to 49 years, and 50 years and older. Although differences
between y nger and middle-age respondents were not substantial for all survey measures of awareness, in most cases
consistent differences were found between the responses of these age groups and 50 years of age and older. The
younger age groups were demonstrably more aware of, and mentioned more, air pollution problems than older
respondents. Likewise, they reported more problems related to general clothing and home furnishings; thought air
pollution caused more of these textile problems; and showed greater concern for the economic costs associated
with textile problems caused by air pollution. Age relationships were not consistent, however, for problems with
clothing that changed color during storage; younger respondents mentioned the least number of such instances.
Nevertheless, most of the above evidence suggests that awareness of and concern with textile problems increase
through youth and middle age and then, at some point, begin to decline with older age as textile needs become less
substantial. For older consumers, textile problems apparently are of less concern and are either ignored or over-
looked.
Length of Residence
Table 5-12 summarizes the influence of length of residence on selected air pollution and textile measures.
More respondents living in their homes for a short tune (less than 5 years), compared to residents of longer periods
(5 years or more), mentioned various concepts of air pollution; experienced both general textile problems and
textile problems possibly caused by air pollution; and tended to attach greater significance to the economic costs
of such problems. More long term residents, however, experienced problems with color changes in clothing during
storage in closets. A possible conclusion is that recent residents are more aware of neighborhood problems, whereas
longer-term residents have learned to accept these conditions and, therefore, mention them less frequently. Other
socioeconomic factors may be influencing these observed relationships.
64 EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
-------
Table 5-10. RELATIONSHIPS BETWEEN FAMILY INCOME AND
SELECTED AIR POLLUTION AND TEXTILE MEASURES
__________ (percent) _____________________
F‘tl O, 0 00/vr
Air pollution and textile measures/responses (n=177)I(n=157)
Respondent concepts of air pollution
Auto and diesel exhausts 37 53
Industrial wastes 25 42
Health problems 31 3 (1
Odors 23 31
Dirt and dust 17 26
Smoke and soot 30 37
Haze or fog 5 11
Other 25 14
Occurrence of problems specifically caused by air
pollution
Yes 41 57
No 58 43
Occurrence of general clothing problems
Yes 32 41
No 68 59
Occurrence of general home furnishings probleris
Yes 23 32
No 77 67
Occurrence of textile problems thought to be
caused by air pollution
Yes 14 18
No 79 67
Not sure 7 15
Occurrence of color changes of clothing stored in closets
Yes 49 51
No 51 49
Colors mentioned:
Blues 25 12
Purples or blacks 10 8
Whites (yellowing or greying) 2 3
Greens or avocados 3 2
Reds or golds 2 1
Browns or beige 2 1
Perceived seriousness of economic costs of textile
problems caused by air pollution
Very serious 7 4
Somewhat serious 20 22
Not serious 59 65
Do not know 15 8
Consumer Awareness 65
-------
Table 5-11. RELATIONSHIPS BETWEEN AGE AND SELECTED
AIR POLLUTION AND TEXTILE MEASURES
________ (percent)
Aqe qrouns, yr
18 to 29 30 to 49 50 and up
Air pollution and textile measures/responses ______ (n=83) ( n 189) (n=122 )
Respondent concepts of air nollution
Auto and diesel exhausts 38 50 31
Industrial wastes 47 35 19
Health problems 30 32 32
Odors 20 31 20
Dirt and dust 22 23 13
Smoke and soot 34 35 25
Haze or fog 12 10 2
Other 18 19 30
Occurrence of problems specifically caused by air
pollution
Yes 49 53 32
No 51 47 67
Occurrence of general clothing problems
Yes 36 41 22
No 64 59 78
Occurrence of general home furnishings problems
Yes 27 35 13
No 73 65 87
Occurrence of textile problems thought to be
caused by air pollution
Yes 19 17 9
No 69 69 88
Notsure 12 14 3
Occurrence of color change of c1oth ng stored in closet
Yes 33 58 46
No 67 42 54
Colors mentioned:
Blues 10 17 25
Purples or blacks 7 7 11
Whites (yellowing or greying) 1 3 2
Greens or avocados 1 2 6
Reds or golds 1 1 1
Brownsorbeige 0 2 2
Perceived seriousness of economic costs of textile
problems caused by air pollution
Very serious 5
Somewhat serious 22 28 9
Not serIous 65 54 67
Do not know 8 11 16
66 EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
-------
Table 5-12. RELATIONSHIPS BETWEEN LENGTH OF RESIDENCE
AND SELECTED AIR POLLUTION AND TEXTILE MEASURES
(percent)
Air pollution and textilèmeasures/responsés
<5yr J ‘.5yr
(n=l28) (n 272)
Respondent concepts of air oollution
Auto and diesel exhausts 45 40
tndustrial wastes 39 29
Health problems 38 29
Odors 29 24
Dirt and dust 29 15
Smoke and soot 31 32
Haze or fog 9 7
Other 22 22
Occurrence of problems specifically caused by air o1lution
Yes 51 43
No 48 56
Occurrence of general clothing problems
Yes 39 32
No 61 68
Occurrence of general home furnishings problems
Yes 30 25
No 70 75
Occurrence of textile problems thought to be caused
by air pollution
Yes 21 12
No 63 81
Not sure 16 7
Occurrence of color changes of clothinq stored in closets
Yes 51 81
No 49 19
Colors mentioned
Blues 12 22
Purples or blacks 8 9
Whites (yellowing or greying) 1 3
Greens or avocados 3 2
Reds or golds 0
Browns or beige 3 1
Perceived seriousness of economic costs of textile problems
caused by air pollution
Very serious 3 8
Somewhat serious 30 16
Not serious 58 61
Do not know 9 15
Consumer Awareness
67
-------
Family Size
Table 513 shows the relationship between family size and selected air pollution and textile survey measures.
In some cases, considerable differences were found between smaller and larger households. More respondents in
larger households (three or more people) than in smajier households mentioned various concepts of air pollution
and general textile problems. The number of respondents experiencing both general air pollution problems and
textile problems believed to be caused by an pollution was about the same for both sizes of households. Larger
households, however, seemed to have a slightly better perception of the seriousness of the increased costs of
textile problems caused by air pollution. This fact should be expected, since larger households consume more
textile products and, therefore, are more likely to experience and observe textile problems. Members of larger
households may also have more opportunity to discuss various problems, including textiles, thus further stimulating
awareness of knowledge of problems.
Heating and Air Conditioning Factors
A final analysis briefly explored the relationships between household heating and air conditioning factors, and
selected air pollution and textile measures. Heating and air conditioning can influence the degree of air contamina-
tion in homes. For instance, air conditioners might effectively seal out pollutants in the summer, while poorly
filtered gas or oil heating systems might increase household contaiminants in the winter. In fact, several respondents
mentioned problems that they thought could be associated with these factors. The results of the analysis, however,
were generally inconclusive on this point and warrant only brief summary.
Households with air conditioning and households with electric heating reported a slightly larger number of air
pollution and textile problems than other households, thus contradicting the hypotheses stated above. The increased
number of problems was most likely a reflection of socioeconomic factors, since air conditioners and electric heating
systems were generally concentrated in homes of people in the upper educational and income brackets. With
respect to color fading problems, differences were minimal. Respondents with gas or oil heating systems tended to
report more color-fading problems, but differences were small.
Some Observations of Respondents
Of considerable interest, apart from the statistical data, are the candid and unsolicited comments made by a
number of respondents. Many are of a general character, while a few are rithly entertaining; some may offer ideas
for further investigation. Even a respondent’s most naive or off-the-record statement may suggest a promising line
of exploratory investigation—a potentially serendipitous byproduct.
Appendix B presents some of the most interesting comments, quoted verbatim. These comments represent a
balanced selection of the most instructive attitudes concerning air pollution expressed by respondents. The com-
ments illustrate the kinds of information they wanted very much to give the interviewers, but which the survey’s
limited queries could not readily yield. Without question, these unsolicited observations, the type of comments that
are infrequently recorded and reported in public opinion research, offer insights that complement impersonal sta-
tistical presentations.
DISCUSSION AND CONCLUSIONS
General Discussion
Air pollution is a recognized problem among urban Americans. Throughout the past decade, a large volume
of air pollution information has been distributed to the public through national and regional mass media and by
68 EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
-------
Table 5-13. RELATIONSHIPS BETWEEN FAMILY SIZE AND SELECTED
AIR POLLUTION AND TEXTILE MEASURES
(percent)
I or2
members
3
members
Air pollution and textile measures/responses
(n=130)
(n 262)
Respondent concepts of air pollution
Auto and diesel exhausts 35 44
Industrial wastes 22 36
Health problems 35 30
Odors 18 29
Dirt and dust 17 20
Smoke and soot 25 34
Hazeorfog 7 8
Other 25 20
Occurrence of problems specifically caused by air pollution
Yes 43 46
No 57 54
Occurrence of general clothing problems
Yes 24 38
No 76 62
Occurrence of general home furnishings problems
18 31
No 82 69
Occurrence of textile problems thought to be caused
by air pollution
Yes 15 14
No 83 72
Notsure 2 13
Occurrence of color changes of clothing stored in closets
Yes 40 52
No 60 48
Colors mentioned:
Blues 19 18
Purples or blacks 8 9
Whites (yellowing or greying) 2 3
Greens or avocados 3
Reds or golds 1
Browns or beige 1 1
Perceived seriousness of economic costs of textile
problems caused by air pollution
Very serious 7 6
Somewhat serious 15 23
Not serious 60 61
Do not know 18 10
Consumer Awareness 69
-------
health organizations, conservation groups, and pollution control authorities. Various opinion surveys show con-
siderable public awareness of the problem. Air pollution awareness has been further stimulated as a result of con-
temporary political and social activism that has focused on the preservation of the natural environment. in view
of the wealth of evidence and increasing public concern, additional evidence that air pollution is a problem of high
national priority appears to be unnecessary.
What is needed now is a more complete understanding of the specific air pollution problems that people
encounter. Detailed information of this type is necessary because the costs of pollution and the benefits of abate-
ment cannot be adequately estimated without a thorough knowledge of all relevant air pollution ramifications.
Philosophically, however, the most significant air pollution costs may be those that are less well defined, such as
impaired health and reduced enjoyment of life. These issues and questions are the difficult ones that investigators
must assess in order to develop a complete understanding of the total air pollution problem.
Investigations of public experiences and problems with air pollution axe complicated by the fact that most
people may. be surprisingly uninformed or unaware of specific air pollution problems. While soiling, malodors and
reduced visibility are obvious problems, the less obvious effects of air pollution on materials and even some health
difficulties may not be fully understood or appreciated by some sectors of our society. The Philadelphia survey
has examined one of these problem: the detrimental effects of air pollution on household textile products. Although
a number of textile problems caused by air pollutants have been verified by laboratory investigations, no previous
study has documented public awareness and experience with these problems. The public opinion survey of 400
randomly selected homemakers in Philadelphia has, therefore, yielded some useful insights.
Conclusions
Consumer Awareness of Air Pollution Effects on Household Textile Products
in measuring consumer awareness of the detrimental effects of air pollution on household textile products,
the investigators evaluated the following observations:
1. Twelve percent of the survey respondents said they had heard or read information on the detrimental
effects of air pollution on textiles, but upon additional questioning concerning the type of information
received only 5 percent mentioned soiling, 5 percent were unable to recall any details, and no more than
3 percent mentioned the important problems of color change or deterioration.
2. Only 8 percent of the respondents perceived that people in general had at least moderate knowledge of
air pollution effects on textiles.
3. Questioned as to whether they thought air pollution caused any of their textile problems, 15 percent
of the respondents answered yes; however, when asked to identify the types of problems they asso-
ciated with air pollution, 12 percent mentioned soiling and only 1 percent color change or deterioration.
Since awareness must include being familiar with all major types of problems and not just the more obvious
effects of soiling, the survey findings strongly indicate that consumer awareness is poorly established and generally
lacking. Apparently, not more than ito 2 percent of all consumers are truly aware of the major air pollution effects
on household textile products.
Importance of Household Textile Problems Caused or Potentially Caused by Air Pollution
The following survey observations were considered in evaluating the importance of the effects of air pollu-
tion on household textile products:
70 EFFECTS OF AIR POLULTANTS ON TEXTILE FIBERS AND DYES
-------
I. Respondents mentioned health (29 percent) and odor (18 percent) problems most frequently when
asked to cite types of personal problems they associated with air pollution, Four percent of those
interviewed mentioned problems with household textiles, however. This fIgure may indicate textile
problems are not important, or that they are important but not cited more frequently because other air
pollution problems are more important and because consumer awareness is limited.
2. When respondents were asked if they had noticed any unusual or unexpected household textile
problems within the last year or so, 34 percent mentioned various difficulties with clothing and 26 per-
cent with home furnishings. Clothing problems mainly concerned quality considerations, all unrelated
to air pollution. In later questioning, however, between 33 and 53 percent of the respondents said they
had noticed such problems as changes in color of clothing during its storage in closets, color changes
in clothing linings, and loss in strength of nylon hosiery. Although this questioning made no reference
to it, air pollution is a major cause of these clothing problems. Furthermore, the most frequently men-
tioned colors that underwent changes were those most sensitive to air pollution. Except under direct
questioning, however, respondents failed to mention these problems, probably because these problems
were not important enough for respondents to recall them and, also because other types of clothing
problems (e.g., quality) were more important. Nevertheless, clothing problems potentially caused by
air pollution apparently do exist.
3. Most of the home furnishings problems cited by the respondents (26 percent) concerned color changes,
soiling, and deterioration, all potentially caused by air pollution. Several respondents even mentioned
air pollution as a possible cause.
4. Asked to identify the types of textile problems they associate with air pollution, 12 percent of the
respondents mentioned soiling, and only a handful mentioned deterioration and color changes.
5. A fairly large segment of the survey population, 28 percent, perceived the economic costs of textile
problems caused by air pollution to be “somewhat to very serious.”
A subjective analysis of these observations leads to the conclusion that the effects, both real and potential,
of air pollution on household textiles, and especially home furnishings, are moderately important but that other
air pollution related problems (health and odors) are probably more important. Soiling is the most frequently men-
tioned type of textile problem that people associate with air pollution; however, this response may be a reflection
of limited consumer awareness of other less obvious types of textile problems—color change, fading, and deterioration.
Public Awareness of Air Pollution and Its Associated Problems
The survey found considerable public awareness of and concern for overall air pollution problems. In identify-
ing general disadvantages associated with living in Philadelphia, 15 percent of the respondents mentioned air pollu-
tion, making it one of the most frequently mentioned problems. About one-half of the respondents did not mention
any specific disadvantages. For the most part, awareness focused on the nuisance aspects of pollution, including
soot, dirt, haze, and odors. Definition of the problem in terms of technical factors, such as specific pollutant gases
or suspended particulates, was significantly nonexistent. Automobiles and industry were frequently mentioned as
major polluters. About two-thirds of the respondents rated air quality as a “very serious” problem in their com-
munity. Almost one-half of the respondents mentioned problems specifically caused by air pollution; those most
frequently identifibd concerned health and odors.
influence of Socioeconomic Factors on the Survey Results
Such socioeconomic factors as place and length of residence, family size, age, education, and income appear
to influence, to varying degrees, air pollution awareness and attitudes. The following observations and comments
support this conclusion:
I. Respondents with more education, higher income, larger families, and a shorter length of residence
generally were more aware of air pollution and associated problems and experienced more difficulties
Consumer Awareness 71
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caused specifically by air pollution. They likewise reported encountering more problems of a general
nature with textile products and more textile problems thought to be caused by air pollution.
2. The younger and, particularly, the middle-age respondents also seemed to be more aware of air
pollution and textile problems than older respondents.
3. A greater percentage of respondents with a longer length of residence, larger families, and of middle age
reported changes in color in clothing stored in closets.
4. Respondents with larger families, a shorter length of residence, and more education attached greater
seriousness to the economic costs of textile problems caused by air pollution.
5. II all the socioeconomic factors were basically equal, one would expect inner-city residents, who live
where air pollution is more prevalent, to be aware of and cite more air pollution problems than suburban
residents. The level of respondents’ reporting of problems, however, was essentially identical in both
areas. Socioeconomic factors probably entered into these findings, for the survey showed that respond-
ents with more education and income were more aware of problems than lower socioeconomic groups.
Apparently, the less aware inner-city residents cited fewer problems than actually existed, while the
more aware suburban residents cited more of the problems than actually existed, thus giving the ap-
perance that both groups experienced about the same number of problems.
Availability of Public Information on the Effects of Air Pollution on Textile Products
Public information about the potential effects of air pollution on textile products is generally lacking. Only
12 percent of the respondents reported having heard or read information on this subject, and respondents generally
felt that people knew very little about it. Many suggested that published information would be useful to home-
makers. Obviously, to increase consumer awareness to the point of usefulness, various trade associations, retail
soups, and government agencies must launch a nationwide information program to enlighten the public.
Economic Consequences
The survey did not attempt to estimate the economic costs of air pollution damage to textiles. The data in
many cases, however, indicated some economic consequences of air pollution, especially in regard to soiling problems.
Respondents recognized increased laundering of textiles as the most important cost of air pollution. Extra
laundering also accelerates deterioration of fabrics, thereby resulting in added costs. Twenty-eight percent of the
respondents judged the added cost of textile problems caused by air pollution to be at least “somewhat serious,”
with increased laundering and clothing deterioration the most frequently mentioned causes of increased costs.
REFERENCES FOR CHAFFER 5
I. Ridker, R. G. Economic Costs of Air Pollution. New York, Frederick A. Praeger, Inc. 1967 215 p.
2. De Groot, 1. Trends in Public Attitudes Toward Air Pollution. J. Air Poll. Contr. Assoc. 17: 679-681,
October 1967.
3. Crowe, M. 1. Toward a “Defunctional Model” of Public Perceptions of Air Pollution. 1. Air Poll. Contr.
Assoc. 18: 154-157, March 1968.
4. Rankin, R. E. Air Pollution Control and Public Apathy. J. Air Poll. Contr. Assoc. 19: 565-569, August
1969.
5. Study to Determine Residential Soiling Costs of Particulate Air Pollution. Prepared under EPA Contract No.
22-69-103 by Booz, Allen and Hamilton, Inc., Washington, D. C U. S. Environmental Protection Agency.
Researdi Triangle Park, N. C. October 1970.
72 EFFECFS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
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6. Report for Consultation on The Metropolitan Philadelphia Interstate Air Quality Control Region (Pennsylvania-
New Jersey-Delaware). U. S. DHEW, PHS, National Air Pollution Control AdministratIon. Washington, D. C.
Publication No. APTD 1218. 1968. 74p.
7. Regional Projections for the Delaware Valley, 1985. Delaware Valley Regional Planning Commission, Plan
Report No. 1. 1967. 79p.
Consumer Awareness
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CHAFFER 6
SUMMARY AND CONCLUSIONS
EFFECTS ON TEXTILE FIBERS
The effects of air pollution on textile fibers vary widely and depend largely on the chemical makeup of the
fiber, kind and concentration of pollutants, and meteorological conditions. Of major concern are the problems
caused by particulates and the effects of the gaseous pollutants sulfur dioxide (SO 2 ), nitrogen oxides (NO,j, and
ozone (03).
Soiling by airborne particles is not only aesthetically objectionable but, more importantly, reduces the service
life of fabrics because of the need for more frequent cleaning and the use of harsher detergents. These stresses con-
tribute to a progressive loss in fiber strength. Soiling is an added problem for fabrics made from manmade fibers
because these fibers acquire electrostatic charges and attract particles. Furthermore, most manmade fibers, unlike
cellulosic and wool fibers, require more potent cleaning agents because they do not readily absorb water-detergent
solutions. Airborne particles may also accelerate the photochemical breakdown of textile fibers, and some metallic
particles may catalyze the oxidation of SO 2 into harmful acids that could attack fabrics.
Sulfur dioxide is the only gaseous pollutant known to damage textiles significantly. This fact has been shown
by both field exposures to ambient levels of SO 2 and by controlled-environment chamber studies using realistic
SO 2 levels. Cellulosic and nylon fibers are the most sensitive of those tested; other fibers seem to be resistant.
Significant damage occurs only when moisture (high relative humidity) and, especially, sunlight (ultraviolet radia-
tion) are present.
The effects of NO and 03 appear to be insignificant. From a theoretical standpoint, however, they are
potentially important because 03 is a powerful oxidizing agent and NOx can form nitric acid.
EFFECTS ON TEXTILE DYES AND ADDITIVES
Although sunlight is the major cause of color defects in dyed textile fabrics, air pollution has also become a
prime factor. Certain dyes used on wool and cellulosic fabrics are mildly sensitive to atmospheric SO 2 , but, overall,
SO 2 does not pose a serious problem. This is not true, however, for atmospheric N0 and 03. Controlled-
environment studies, together with outdoor service trials and consumer complaints, show that levels of these pol-
lutants existing in the ambient environment can react with a number of dyes and produce noticeable color changes.
Even levels found in nonindustrial and semirural areas are frequently sufficient to cause fading.
Nitrogen oxides largely consist of nitrogen dioxide (NO 2 ) and nitric oxide (NO), but practically all fading is
caused by NO 2 . This pollutant can produce color changes in vulnerable dyes (mainly blues) used on cotton, rayon,
acetate, and nylon fabrics. Nitrogen dioxide can also cause a yellow discoloration on undyed white fabrics when
certain vulnerable additives such as optical brighteners, softeners, soil-release finishes, and processing agents are
used. High relative humidity is a critical factor in NO damage to textiles, especially for cotton and rayon fabrics.
Major fading complaints attributable to N0 damage, have come from families using gas-fired clothes dryers and
smog areas such as Los Angeles. In addition, producers and distributors of clothing have experienced costly inci-
dents in which large numbers of garmets have faded in warehouses.
75
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Atmospheric ozone produces color defects on vulnerable dyes used on cotton, rayon, acetate, nylon, and
polyester/cotton permanent-press fabrics. Some of these dyes are sensitive to both ozone and NO 2 , while others
are resistant to NO 2 but sensitive to ozone. 1-ligh relative humidities (80 to 90%) greatly accelerate ozone fading.
This is especially true for cellulosic and nylon fibers; pronounced fading takes place on exposure to high humidity
conditions, while little color change is noted at relative humidities below 65 percent. Color changes in permanent-
press fabrics and the disastrous fading of nylon carpets are prime examples of unexpected problems caused by
ozone.
General measures to alleviate or prevent fading by air pollution include the proper selection of resistant dyes
and the use of quality inhibitors and additives.
CONCLUSIONS
Clothing makes up a major portion of all manufactured textile products. The life of much clothing, however,
depends more on fashion and style changes than on impairment and wear. Consumers often discard their clothing
within I to 3 years. Because of fashion obsolescence and also because most clothing is in storage more often than it
is worn, air pollution in many cases does not have enough time to cause significant damage, especially if fabrics have
at least minimum protection against dye fading. Therefore, while damage problems do occur from time to time,
the effects of air pollution on clothing do not appear to be generally a serious problem today.
The same can not be said for textiles used in household furnishings. The life of furniture upholstery,
draperies, curtains, and carpets may be anywhere from 5 to 15 years. This amount of time is sufficient for air pol-
lutants to react and produce significant damage problems. The effects of air pollution must also be considered by
manufacturers of such products as tarpaulins, cordage, awnings, and flags.
Within the textile industry, the judicious selection of fibers, dyes, inhibitors, and additives is a matter of
delicate balance that management must make to achieve a desired degree of quality and performance at lowest
possible cost. Air pollution plays an important role in this “balancing act.” As a result of steps taken to mitigate
air pollution damage, plus an increasing demand for higher quality goods, the production of fabrics sensitive to air
pollutants is gradually decreasing.
In the long run, the greatest problem associated with air pollution may be an intangible loss in man’s enjoy-
ment of his property. The public may accept air pollution as a “fact of life,” and may feel that nothing can be or
will be done to correct it. Furthermore, people may learn to live with a problem and ignore or otherwise psychologi-
cally submerge its effects on daily living. Such apathy and cynicism are contagious and, when widespread in the
population, may make the enforcement of air pollution controls difficult. This possible danger emphasizes the
need to bring to the attention of the public the wide range of air pollution effects that can occur.
76 EFFECFS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
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APPENDICES
A. QUESTIONNAIRE-
PHILADELPHIA TELEPHONE SURVEY
B. UNSOLICITED COMMENTS-
PHILADELPHIA TELEPHONE SURVEY
77
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Phone No.
APPENDIX A. QUESTIONNAIRE-
PHILADELPHIA TELEPHONE SURVEY
Address
Respondent No. Cl-3
Interviewer No. C4
AreaofCityNo. CS
Call
Completed
Refused
Callback
Comment
I
2
3
4
“Hello, this is (interviewer’s name) of The University of North Carolina at Greensboro.
I’m calling long distance on a University of North Carolina study of some problems of
interest to homemakers in the Philadelphia area. Your ideas will be of great value to our
study; would you talk with me for a moment?” (Establish whether respondent is the
“lady of the house.” Interview only the female head.of-household.)
1. About how many years have you lived in the Philadelphia area, or Philadelphia
County?
________ Years
O_ lOormore
C6
2. How many years have you lived in this specific home?
________ Years
0 - lOormore
C7
3. Can you think of any problems or things you don’t like about living in your area of
the city? (PROBE—Do not read list to respondent)
4. Let’s talk about your clothing and your family’s clothing for a moment. In the past
year or so, have you noticed any unusual or unexpected clothing damage problems,
such as color fading, color changes, soiling or wearing out? (PROBE FOR INFOR-
MATION—”By this I mean clothing that did not last as long or wear as well as you
expected. . .“)
1. ____ Yes 2. No IF YES, ask Q. 4a. C9 ___________
IF NO: “You can’t think of anything that lost its color or wore out unusually fast?”
1. ____ Air polution
2. Vandalism or crime
3. Poor schools
4. Poor stores
5. ____ Inconvenient shopping
6. ____ Traffic or congestion
7. _____ Noise
8. _____ Poor recreation facilities
9. ____ No specific problems
0. ____ Other
C8
79
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4a . Can you describe some of these problems to me? (Record only potential air pollu-
lion problems.)
5. Have you ever noticed any unusual or unexpected damage to any of your curtains,
carpets, blankets, furniture materials, or other home furnishings? (PROBE for in-
formation similar to Q. 4.)
2._ No IFYES,askQ.5a.
5a. Can you describe some of these problems to me?
Fiber/color What and where happened; perceived cause
Number of non-air pollution problems mentioned
6. Occasionally we hear the term “air pollution.” When you hear the term air pollu-
tion, what sort of specific things do you think of’? (PROBE—Do not read list to
respondent.)
7. Have you ever had any problems or complaints which you thought were specifically
caused by air pollution?
2. — No IF YES, ask Q. 7a.
Is. Can you describe some of these problems to me?
I. ____ Health problem or irritation
2. Odor problem
3. ____ Clothing or textile problem
4. ____ Plant damage
5. — Damage to other materials
6. Made a complaint to some agency
7. ____ Other
8. In general, would you say that air pollution is a very serious, somewhat serious, or
not serious problem in your community?
Item
1. ___Yes
Item
I. Auto, diesel exhausts
2. ____ Industrial wastes
3. ___ Health problems and irritations
4. ___ Odors
5. ____ Dirt or dust
Number of non-air pollution problems mentioned_____________________ Cl 0
Fiber/color What and where happened; perceived cause
_________________________________________ Cll-17 ________
_______________________________________ Cl 8-24 ________
C25
C26-31
C32-37 _________
C38 _________
____ C39
C40
C41
C4244
C45
6. ____Textile damage
7. ____ Other material damage
8. — Smoke, soot, or gases
9._ Hazeorfog
0. —__Other
1. ___ Yes
If clothing or home furnishings problem, describe:
1. Very serious
2. ___ Somewhat serious
3. — Not serious
4. — Don’t know
EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
-------
9. Have you ever heard or read any information on the effects of air pollution on
clothing or home furnishings?
1. Yes 2. No IF YES, ask Q. 9a-b. C46 __________
9a. Do you remember what this source of information was, or who gave you the
information?
______________________________ 0 ____ Don’t recall C47 __________
9b. Do you recall what information you received?
— 0 — Don’t recall C48 ___________
10. Have you ever read clothing hang tags or asked salespeople for information on the
resistance of clothing to air pollution damage or gas fading? (PROBE for specific
information sources sought.)
1. — Never searched for information 4. — Salesperson C49 ___________
2. — Hang tags 5. — Other personal source
3. — Other sales literature 6. — Other
11. Would you say that most people know quite a bit, a moderate amount, or not much
at all about the effects of air pollution on clothing and home furnishings?
1. — Quite a bit 3. — Not much at all C50 __________
2. — Moderate amount 4. Don’t know
12. Have you ever noticed any damage to clothing or home furnishings that you think
might be caused by air pollution?
I. — Yes 2. — No 3. Not sure (Do not know) C51
IF YES OR NOT SURE, ask Q. 12a. and 12b.
1 2a. Can you describe some of these problems to me?
Pro4uct Damqge noticed; how often noticed
____________________________ _____________________________________ C52-56 ________
__________________________ ___________________________________ C57-61 ________
1 2b. Were any of these items discarded because of the air pollution damage?
1._Yes 2._ No C62 ________
13. Have you ever taken any clothing or home furnishing back to a retail store for any
adjustment or to make a complaint?
I. — Yes 2. No IF YES, ask Q. 13a. C63
13a. What was the problem?
1. Style or fit change 3. — Other poor performance CM __________
2. — Air pollution problem 4. — Other
Appendix A. Questionnaire-Philadelphia Telephone Survey 81
-------
14. Have you ever noticed any of the following clothing or home furnishing problems?
You can answer yes or no on each of these...
(1) (2)
Yes No
a. Clothing that fades or changes color in the closet,
even though not worn C65 __________
b. Change in color of clothing linings C66 —
c. Color change of clothing, curtains, or other things made
of acetate material C67
d. Color change of your home carpets C68 __________
e. Loss of strength or breaking of nylon hose not caused
by runs or snags C69 __________
f. Color change in curtains above or below the window
or where not exposed to sunlight C70 ___________
15. In general, would you say that air pollution effects on clothing and home furnishings
cause a very serious, somewhat serious, or not serious money cost to you?
1. Very serious 3. — Not serious Cu
2. — Somewhat serious 4. — Don’t know
IF VERY OR SOMEWHAT SERIOUS, ask Q. 1 5a.
15a. Why do you say that?
1. ____ Because of increased laundering 4. ____ No special reason C72 ___________
2. Clothing deteriorates faster 5. ____ Other
3. Clothing doesn’t look good
16. Do you have electric, gas, coal, or oil heating in your home?
1._Electric 2._Gas 3._Coal 4._Oil 5._Other C73
17. Do you have any air conditioners in your home?
1.— Home completely AC 2 . Some AC 3. — No AC C74 —
18. How many people, including yourself, live in your home with you?
____________ Number C75
19. In which of these age groups arc you?
1. — 18 to 29 years 4. ____ 50 to 59 years C76
2. — 30 to 39 years 5. ____ 60 years and over
3. — 40 to 49 years 6. ____ Refused
20. Approximately how far did you go in school?
1. — Some grammar or high school 3. ____ Some college C77
2. — High school graduate 4. — Completed 4 or more
years of college
21. In which of these approximate income ranges does your total family yearly income
fall’ (Attempt to obtain broad classification of before tax income.)
1._Under $6,000 3._ $10,000 to $14,999 5............Don’t know C78 -
2._$6,000 to $9,999 4._ $15,000 and up 6._Refused
82 EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS AND DYES
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APPENDIX B. UNSOLICITED COMMENTS-
PHILADELPHIA TELEPHONE SURVEY
AIR POLLUTION AS AN URBAN PROBLEM
“The air is not fit to breathe.”
“No one seems to be bothered by air pollution too much. . . I mean they don’t do anything. They say if you can
live in Philadelphia, you can live anywhere. Maybe we’re immune to it . .
“Why didn’t they start worrying about air pollution a long time ago ..
“Most people don’t get too upset about it (air pollution) because there is not too much they can do.”
“I used to have some air pollution problems until I moved to the ‘country’ (Philadelphia suburb) . .
“Air pollution doesn’t bother me, I live in the suburbs.. . the people in the city and slums talk about it a lot,
they know more about it ..
“I moved to this new home to get away from the air pollution where I used to live . . .“
“There is a factory at the end of the street ... We have complained to the mayor and written petitions (about
air pollution), but they always say they will do something and nqthing is done . . .“
“Factories are good for people too . .
“People get used to living with air pollution and don’t notice the effects.”
“I don’t believe there is that much problem . . . the sky looks nice . .
“Who cares (about air pollution damage to materials)? It’s an affluent society. . . health is the big problem . .
“I’m getting the h--- out of this filthy city ..
“If you want to learn about air pollution come up here . .
“As a mother of six, air pollution is the least of my problems. . . why don’t you do some research on sex . .
“Why would anyone in North Carolina be interested in my air pollution problem, are you really calling long
distance anyway..
MATERIAL DAMAGE
“1 didn’t really think of air pollution hurting materials, but now that you mention it
83
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“This material damage problem (from air pollution) is something women don’t know about, but 1 think I’ll
start watching for it now that I know it’s a problem . .
“Black soot gets all over your clothes outside . . .“
“Soiling could be from air pollution. . . it causes a definite increase in costs .. .“
“The effects of air pollution on clothing are not serious because I really don’t know . . - it could be happening and
I did not attribute it to air pollution . . .“
“My nylon curtains have rotted in spots. . . something might have come in from the window ..
“Nylon stockings seem to deteriorate faster now. . . this is particularly noticeable now that I spend 30 minutes
a day in downtown Philadelphia waiting for the bus . .
“One damage problem I think was caused by air pollution was my curtains fading in a vety short time .. .“
‘1 have to wash my chair covers and curtains every two weeks because of the soot. . . they will wear out sooner . - .“
“The new materials are good, I really don’t think that air pollution has any effect on clothing or home fur-
nishings...”
“What am I supposed to do now - . . get all hepped up on air pollution as it affects my clothes.. . ?“
“Get rid of the air pollution and you won’t have any damage problems . . .“
INFORMATION SOURCES
“The girls never talk about air pollution damage, so I guess I just don’t know about it . . . it may be a problem . . .“
“Women don’t talk much about air pollution . .
“I never read anything about air pollution hurting materials; why don’t you write something about it . .
“If you ever write a book about this study and it does not cost too much, I would like to buy it .
“Scientists know a lot about the effects of air pollution on clothing and home furnishings. . . they should make
more information available to the homemaker . . .“
“I’ve read aitides on air pollution’s effects on clothing.. . they made me more alert to the everyday effects . . - I
think the public in general is usually unaware of the problem . -
“Most people know very little about the effects of air pollution on clothing and home furnishings, except in areas
where everything just falls apart - .
“People know about air pollution effects on clothing but are indifferent to it.. . do you think they are going
to do anything about it..
“I never thought about looking for information on the resistance of clothing and home furnishings to air
pollution damage .. .“
“People don’t know enough about air pollution damage on textiles. . - it should be publicized on TV . - .“
“People just agitate a lot about air pollution. . - they don’t know too much about it . . .“
“I’ve read so much about air pollution 1 don’t want to see any more . .
84 EFFECTS OF AIR POLLUTANTS ON TEXTILE FIBERS ANt) DYES
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TECHNICAL REPORT DATA
‘Plcase read fusiruc (ions on the re e’rse before completing)
2.
-
3.
5. REPORT DATE
.
on Textile Fibers and
Dyes
February 1975
6. PERFORMING ORGANIZATION CODE
B. PERFORMING ORGANIZATION REPORT NO.
Sal in
ELEMENT NO.
ADDRESS
Agency - NERC
C. 27511
Greensboro, N.C.
27412
P1-122-68-2 In-house
ADDRESS
13. TYPE OP REPORT AND PERIOD COVERED
Agency
Center
Final
14. SPONSORING AGENCY CODE
C. 27511
16. ABSTRACT This document presents: (1) a comprehensive survey of the dmriaging effects oi
air pollutants - particulates, SON, NON, and ozone - on textile fibers and dyes, and
(2) the results and assessment of a public opinion survey to primarily measure consumer
awareness of the detrimental effects of air pollution on household textile products.
Nearly 100 references are cited and many of the research investigations are detailed
and discussed.
The survey found that air pollution represents a sigiiificant problem area for the
textile industry and many consumers. Major individual problems include (1) excess
soiling of fabrics, (2) loss-in-strength of cellulosic and nylon materIals by acids
derived from SON, (3) fading of certain dyed cellulosic, acetate, and nylon fabrics by
NO 2 and/or ozone, (4) yellow discoloration of in dyed white fabrics by NO 2 , (5) fading
of permanent press polyester/cotton fabrics by ozone, and (6) fading of certain dyed
nylon carpets by ozone. The public opinion survey revealed that consumer awareness
of nylon carpets by ozone. The public opinion survey revealed that consumer awareness
of the major air pollution effects on household textile products is poorly establishec
and generally lacking.
I?. KEY WORDS AND DOCUMENT ANALYSIS
a. F IIPTtD ‘OPEN ENDED TERMS
effects - materials, textiles, textile
dyes, deterioration, discoloration, fading
soiling, particulates, nitrogen oxides,
sulfur oxides, ozone, opinion surveys,
social attitudes, consumer awareness.
C. COSAT FiCk1/G!OUP
.
NO. OF PAGES
18. DISTRIBUTION STATEMENT
Release unlimited
19. SECURITY CLASS (This Reportj
UNCLASSIFIED 94
20. SECURITY CLASS (This page) 22. PRICE
UNCLASSIFIED
EPA Foyni 222O . (9.73)
85
12.5. GOVERNMENT PRXUTIME 0F73C4: 1975 — 640-88C/652 - Region 4
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