OCR error (C:\Conversion\JobRoot\00000CUW\tiff\20015OB2.tif): Unspecified error
-------
RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U S Environmental
Protection Agency, have been grouped into nine series These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields
The nine series are
1 Environmental Health Effects Research
2 Environmental Protection Technology
3 Ecological Research
4 Environmental Monitoring
5 Socioeconomic Environmental Studies
6 Scientific and Technical Assessment Reports (STAR)
7 Interagency Energy-Environment Research and Development
8. "Special" Reports
9 Miscellaneous Reports
This report has been assigned to the ENVIRONMENTAL MONITORING series.
This series describes research conducted to develop new or improved methods
and instrumentation for the identification and quantification of environmental
pollutants at the lowest conceivably significant concentrations It also includes
studies to determine the ambient concentrations of pollutants in the environment
and/or the variance ot pollutants as a function of time or meteorological factors
This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161
-------
EPA-600/4-80-007
January 1980
REGIONAL AIR POLLUTION STUDY
Effects of Airborne Sulfur Pollutants on Materials
by
F. Mansfeld
Rockwell International
Environmental Monitoring & Services Center
Environmental & Energy Systems Division
11640 Administration Drive
Creve Coeur, MO 63141
Contract No. 68-02-2093
Task Order 112
Project Officer
Fred H. Haynie
Atmospheric Chemistry and Physics Division
Environmental Sciences Research Laboratory
Research Triangle Park, North Carolina 27711
ENVIRONMENTAL SCIENCES RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
RESEARCH TRIANGLE PARK, NORTH CAROLINA 27711
-------
DISCLAIMER
This report has been reviewed by the Environmental Sciences Research
Laboratory, U.S. Environmental Protection Agency, and approved for publication,
Approval does not signify that the contents necessarily reflect the views and
policies of the U.S. Environmental Protection Agency, nor does mention of
trade names or commercial products constitute endorsement or recommendation
for use.
-------
ABSTRACT
This report discusses the results obtained between October 1974 and
March 1977 in an exposure study at nine test sites in St. Louis, Missouri,
under Task Orders Nos. 26 and 112 as part of the Regional Air Pollution Study
(RAPS). Samples of galvanized steel, weathering steel, Al 2014 and 7079 ten-
sile samples, silver, marble, nylon and two types of house paint have been
exposed for various lengths of time. Atmospheric data which include wind speed
and direction, temperature, relative humidity (RH), total sulfur, S0?, hLS,
03, NO,,, total hydrocarbon, total suspended particulates, sulfate and nitrate
have been collected at each exposure site under the Regional Air Monitoring
System (RAMS).
For galvanized steel and weathering steel, four different sets have been
exposed in order to study the effect of the atmospheric conditions at first
exposure on subsequent corrosion behavior. For galvanized steel a pronounced
effect of time of first exposure was observed, while the corrosion behavior of
weathering steel did not seem to depend on the seasonal effects. The corrosion
kinetics of galvanized steel were shown to be different for first exposure in
the fall and winter as compared to first exposure in the spring or summer, where
linear corrosion kinetics and lower corrosion rates were observed.
House paint showed discontinuous corrosion behavior with the highest cor-
rosion rates being observed between October 1974 and January 1975, and between
April and October 1975. Exposure to the south was more corrosive than exposure
to the north for both latex and oil base paint. The integral corrosion rates
for latex base paint were higher than those for oil base paint.
The corrosion rate of marble decreased with time at all sites.
Tarnishing of silver plated samples was measured by the reflectance loss
and by an electrochemical technique. At some sites 50% reflectance loss
occurred after 3 months exposure.
111
-------
All nine samples of Al 7079 at 25 Ksi failed in less than 255 days,
while complete failure at 15 Ksi occurred between 277 and 630 days. At one
site (#120) one sample remained unbroken. For Al 2014 more scatter in the
time-to-failure was observed. At sites #103 and 120 all samples at 45 Ksi
failed in 66 and 83 days, respectively, while one sample remained unbroken
after 30 months at each of sites #112 and 115. At 25 Ksi, all samples
cracked only at sites #105 and 108.
The tests with nylon filament which fails when in contact with acid
drops proved to be inconclusive.
The pollution levels in St. Louis were found to be rather low. The
quarterly SCL averages exceeded 20 ppm only at sites #105, 108, 115 and 122
between November 1974 and April 1975. For many days during the thirty month
test period the SOp, H~S and total sulfur levels did not exceed the detection
limits of the instruments. The ozone concentration showed similar seasonal
changes as the temperature. Sites which were close to the center of St. Louis
had lower ozone but higher NO,, and total hydrocarbon levels. The sulfate con-
centration was about twice as high in the summer months as in the winter
months.
A first attempt has been made to provide a statistical correlation
between corrosion and atmospheric data using a multiple regression model.
Some of the apparent inconsistencies which seem to occur in the estimated
effects of pollutants on corrosion behavior are believed to be due to multi-
collinearity.
Corrosion (CCN) and Pollutant Code Numbers (PCN) have been assigned to
each test site based on the average corrosion values and pollutant levels.
No obvious correlations between corrosion behavior and atmospheric conditions
can be obtained by comparison of these numbers.
A number of additional experiments have been carried out during this
program which were not required under Task Orders No. 26 or 112. The results
of tests, which were provided by the persons responsible for the individual
experiments, are described in the Appendix. Al samples have been exposed by
ALCOA in order to determine the nature of the corrosion products formed
during exposure at the different test sites and to correlate these findings
IV
-------
with the stress corrosion cracking behavior of the Al tensile samples.
Washington University exposed bronze samples at five test sites to provide
fundamental data for their outdoor bronze monument conservation program.
CLIMAT samples obtained from ARMCO Steel Corporation have been exposed at
all sites. Results for one year starting in April 1976 have suggested that
the corrosivity of these test sites is negligible. Atmospheric corrosion
monitors exposed by Rockwell Science Center personnel have been used to
provide continuous records of time-of-wetness and corrosivity at up to four
test sites.
-------
CONTENTS
Abstract 1"
Figures ix
Tables xii
Acknowledgment X1V
1.0 Introduction 1
2.0 Outline of Test Plan 2
2.1 Materials, Exposure Conditions and Assessment of
Corrosion Damage 2
2.2 Exposure Sites 2
2.3 Exposure and Removal Schedule 3
2.4 Air Quality Data 3
2.5 Additional Experiments 3
3.0 Corrosion Data - Results and Discussion 5
3.1 Galvanized Steel 6
3.2 Weathering Steel 8
3.3 House Paint 9
3.4 Marble 9
3.5 Silver 10
3.6 Aluminum Tension Samples 11
3.7 Nylon 12
4.0 Air Quality Data - Results and Discussion 13
4.1 Sulfur Dioxide 14
4.2 Hydrogen Sulfide 15
4.3 Total Sulfur 15
4.4 Ozone 16
4.5 Oxides of Nitrogen 16
4.6 Total Hydrocarbon 17
4.7 Wind Speed, Wind Direction, Temperature and Relative Humidity 17
vii
-------
CONTENTS (continued)
4.8 Particulate Matter 17
5.0 Correlation Between Corrosion and Atmospheric Data 19
5.1 Introduction 19
5.2 The Statistical Model 20
5.3 Results 21
5.3.1 Galvanized Steel 22
5.3.1.1 First Set 22
5.3.1.2 Second Set 23
5.3.1.3 Third Set 23
5.3.1.4 Fourth Set 23
5.3.2 Weathering Steel 24
5.3.2.1 First Set 24
5.3.2.2 Second Set 24
5.3.2.3 Third Set 24
5.3.2.4 Fourth Set 24
5.3.3 House Paint, Latex Facing North 25
5.3.4 House Paint, Latex Facing South 25
5.3.5 House Paint, Oil Facing North 25
5.3.6 House Paint, Oil Facing South 26
5.3.7 Marble 26
5.4 Corrosion and Pollutant Code Numbers 27
References 29
Appendix A - Additional Exposure Tests 145
vm
-------
FIGURES
Number Paqe
1 Arrangement of test racks on shelter roof 30
2 Locations of test sites 31
3 Def. of integral (V-) and differential (V.) corrosion rates
(Ref. 6) n d 32
4 Weight loss of galvanized steel, first set, at the nine
test sites 33
5 Weight loss for four sets of galvanized steel at sites #103
and 112 34
6 Log-log plot of weight loss of galvanized steel at site
#103 as a function of time 35
7 Integral corrosion rates V. for four sets of galvanized
steel at the nine test sites 36
8 Weight loss of weathering steel, first set, at the nine
test sites 37
9 Weight loss of four sets of weathering steel at sites #103
and 112 38
10 Log-log plot of weight loss of weathering steel at site #103
as a function of time 39
11 Integral corrosion rates V. four four sets of weathering
steel at the nine test sites 40
12 Log-log plot of integral corrosion rates for the first set
of weathering steel at all test sites as a function of time 41
13 Weight loss and integral corrosion rates for house paint
at site #103 42
14 Integral corrosion rates for house paint at the nine test sites 43
15 Log-log plot of weight loss of house paint at site #103 as a
function of time 44
16 Weight loss of marble at sites #106 and #122 over a
thirty-month period 45
17 Integral corrosion rates V. for marble at nine test sites 46
18 Log Am-log time plot for marble at sites #103, 115, and 122 47
19 Cathodic reduction of tarnish film on silver 48
-------
FIGURES (continued)
Page
48
49
50
51
52
53
54
55
56
57
58
Number
20
21
22
23
Relationship between reflectance loss RL (%) and amount
of electricity (Cb) used to reduce tarnish film on silver
exposed at nine sites during first year of exposure
Relationship between reflectance loss RL (%) and amount
of electricity (Cb) used to reduce tarnish film on silver
exposed at nine sites during second year of exposure
Percent of Al tension samples surviving (n ) as a function
of time for all nine test sites
22a. Site #103
22b. Site #105
22c. Site #106
22d. Site #108
22e. Site #112
22f. Site #115
22g. Site #118
22h. Site #120
22i. Site #122
Three-month averages of air quality parameters for the time
between Nov. 10, 1974 and March 31, 1977 at sites #103,
106, 118 and 122.
23a. Wind speed
23b. Wind direction
23c. Temperature
23d. Relative humidity
23e. Total sulfur
23f. S02
23g. H2S
23h. Ozone
23i. NOX
23j. THC
59
60
61
62
63
64
65
66
67
68
-------
FIGURES (continued)
Number Page
24 Three-month averages of particulate matter for the time
between Nov. 10, 1974 and March 31, 1977 at sites #103, 106,
118 and 122.
24a. Total suspended particulates (yg/m3) 69
24b. Sulfate (yg/m3) 70
24c. Nitrate (yg/m3) 71
25 Averages of air quality parameters for different exposure
lengths and start of exposure.
25a. Total sulfur (ppb) 72
25b. Sulfur dioxide (ppb) 73
25c. Hydrogen sulfide (ppb) 74
25d. Ozone (ppb) 75
25e. Oxides of nitrogen (ppb) 76
25f. Total hydrocarbon (ppm) 77
26 Averages of particulate matter for different exposure
lengths and start of exposure.
26a. Total suspended particulates (yg/m3) 78
26b. Sulfate (yg/m3) 79
26c. Nitrate (yg/m3) 80
-------
TABLES
Number Page
1 Materials, preparation, exposure conditions and
assessment of corrosion damage 81
2 Air quality data used for this project 82
3 Weight loss of galvanized steel (mg) 83
2
4 Integral corrosion rates V- (yg/cm month) for
galvanized steel (area = 310 cm2) 85
5 Corrosion parameters n and k for galvanized steel
(k in mg/cm2 month) 87
6 Weight loss of weathering steel (mg) 88
7 Corrosion parameters n and k for weathering steel
(k in mg/cm2 month) 91
8 Integral corrosion rates V. (mg/cm2 month) for weathering
steel (area = 310 cm2) 92
9 Differential corrosion rates (ym/yr) for weathering steel
calculated according to Eq. (5) 94
10 Weight loss of house paint on stainless steel (mg)
(average of 3 samples) 96
11 Integral corrosion rates V- (ug/cm2 month) for house paint
(area = 155 cm2) 98
12 Weight loss data for marble (mg) (average of 3 samples) 100
13 Corrosion rates V. (ug/cm2 month) for marble
(total area = 366 cm2) 100
14a Average reflectance loss (%) for Ag, first year
(average of 4 measurements per sample, duplicate samples) 101
14b Reflectance loss and film thickness for Ag, first year
(values correspond to one of the duplicate samples in
Table 14a) 101
15a Average reflectance loss (%) for Ag, second year
(average of 4 measurements per sample, duplicate samples) 102
15b Reflectance loss and film thickness for Ag, second year
(values correspond to one of the duplicate samples in
Table 15a) 102
16 Time-to-failure of Al tension samples (days) 103
xii
-------
TABLES (continued)
Number Page
17 Results of nylon exposure 104
18 Quarterly averages of air quality data for the period
between Nov. 10, 1974 and March 31, 1977 105
19 Quarterly averages of total suspended particulates,
sulfates and nitrates (yg/m^) 111
20 Average concentration for different exposure periods and
start of exposure 116
21a Weighted averages for total suspended particulates (yg/nr) 128
21b Weighted averages for sulfate (yg/m^) 130
o
21c Weighted averages for nitrate (yg/m ) 132
22a Results of regression analysis for galvanized steel 134
22b Results of regression analysis for weathering steel 136
22c Results of regression analysis for house paint 138
22d Results of regression analysis for marble 141
23 Test of hypothesis that regression coefficient is zero 142
24 Overall ranking of test sites according to corrosion data 143
25 Overall ranking of test sites according to pollutant
concentrations 144
-------
ACKNOWLEDGMENT
The author acknowledges the help of J. V. Kenkel, S. L. Jeanjaquet and
S. C. Tsai of the Science Center, who prepared all samples and determined the
corrosion damage. Dr. K. Murthy and K. W. Fertig provided the statistical
analyses. J. C. Gysbers of the Science Center prepared computer programs to
obtain the air quality data from computer tapes received from the Air Monitor-
ing Center, St. Louis. Dr. G. Colovos of the Air Monitoring Center (AMC),
Newbury Park, provided chemical analyses of the hi-vol data. W. R. Krone,
E. Nelson, S. Nelson and D. Kalin of the AMC, St. Louis exposed and collected
the samples at the exposure sites. Dr. R. L. Myers, Dr. C. S. Burton, D. H.
Hern and M. Taterka assisted the program in various areas.
. Dr. E. H. Phelps of the United States Steel Corporation arranged for
deoxidation of the weathering steel samples at his laboratory free of charge;
D. 0. Sprowls and B. W. Lifka provided analyses of corrosion data on Al sheet;
and H. H. Lawson provided CLIMAT samples and anaylsis of the corrosion data.
The Georgia Marble Company donated the White Cherokee Marble used in this
study.
xiv
-------
1.0 INTRODUCTION
In April 1974, the Environmental Protection Agency issued Task Order
No. 26 under the Regional Air Pollution Study (RAPS) in St. Louis to begin a
four-year exposure study which would assess the damaging effects of sulfur
pollutants on various materials. This field study complemented laboratory
work carried out by the Materials Section of EPA using controlled environment
chamber studies for evaluating the interaction of pollutants such as sulfur
dioxide, ozone, oxides of nitrogen, and various materials.
Upon receiving Task Order No. 26, Science Center personnel developed a
study plan, acquired material and equipment, erected exposure racks at
selected test sites and commenced the exposure program during October 1974.
Task Order No. 112 was initiated in May 1976 to continue the exposure study.
This report covers the results obtained during the thirty-month exposure
period between October 1974 and April 1977 when the project was terminated.
Included are corrosion damage data and a summary of atmospheric data collected
during this period. An attempt to correlate corrosion and atmospheric data
has been made.
-------
2.0 OUTLINE OF TEST PLAN
2.1 MATERIALS, EXPOSURE CONDITIONS AND ASSESSMENT OF CORROSION DAMAGE
The materials for this study were selected by the Materials Section of
EPA. Table 1 lists the materials studied, the preparation of the samples,
the exposure conditions and the methods of assessment of corrosion damage.
A more detailed description is given in Ref. 1. The exposure racks for
exposure at 30° from horizontal facing south constructed per ASTM specifica-
tions were purchased from the 01 in Corporation, New Haven, Connecticut.
Exposure racks for vertical exposure of house paint on stainless steel were
designed and fabricated at the Science Center using redwood panels to hold
the samples in an aluminum frame. The samples were held in placed using
porcelain insulators. The holders for the nylon samples were located on
both sides of the top of the rack. The Al tension samples, which were
purchased from Alcoa Technical Center, Alcoa Center, Pennsylvania, were
delivered stressed to a fixed stess level (Table 1) and mounted in test
frames. The arrangement of the test racks on the roofs of the RAMS shelters
is shown in Figure 1.
2.2 EXPOSURE SITES
The Regional Air Monitoring System (RAMS) in St. Louis consisted of 25
stations for collection of aerometric data. A description of this completely
automated system can be found in Ref. 3. The nine sites shown in Figure 2
on an inner and an outer ring were selected for this study based on criteria
related to monitoring of air quality data important for this exposure study
including analysis of particulate matter, which is not provided at all RAMS
sites, and to a reasonable spread of the test sites in the area covered in
the RAMS study.
-------
2.3 EXPOSURE AND REMOVAL SCHEDULE
The basic exposure and removal schedule was provided by the EPA in Task
Order No. 26. This schedule was followed with the exception that additional
samples of galvanized and weathering steel were exposed at three-month in-
tervals during the first year to allow a study of the effects of seasonal
variations on the corrosion behavior of these materials. The total number of
samples at a given test site reached a maximum nine months after start of the
exposure test and declined until the end of the program in March 1977.
2.4 AIR QUALITY DATA
Air quality data were routinely collected at each RAMS test site. For
the exposure study, the parameters listed in Table 2 were considered important.
These data were received from the St. Louis branch of the Rockwell Inter-
national Air Monitoring Center on tapes in the form of one-hour averages with
the exception of sulfate, nitrate and particulate matter data, which were
prepared from hi-vol data at the Thousand Oaks branch of the Air Monitoring
Center.
The hourly averages received from St. Louis were further processed at
the Science Center to produce daily and weekly averages, maxima and minima
and standard deviations as discussed in the one-year (1) and two-year (2)
reports! For this final report only validated quarterly average data re-
ceived from AMC St. Louis for the various exposure periods were used.
2.5 ADDITIONAL EXPERIMENTS
A number of experiments not included in the Task Order specifications
were added to the program at various times. Since samples for the tests were
provided and analyses of the results carried out by the persons who were
responsible for these experiments, no additional costs were incurred. The
Alcoa Technical Center requested permission to expose a number of different
- - 2~
aluminum alloys for determination of pH, Cl , N0_ and SO, content of the
corrosion products, and metallographic determination of type and depth of
attack. These panels were exposed at the start of the program at all sites.
In April 1976 the first set of CLIMAT (CLassification of Industrial and
Marine ATmospheres) devices was exposed at all sites. Professor D. W.
-------
Zimmerman of Washington University in St. Louis exposed samples of two dif-
ferent bronzes at five sites in April 1975. Finally, atmospheric corrosion
monitors (ACM) as described by Mansfeld and Kenkel (4,5) were exposed at
different times and different test sites. Results from these additional
exposure tests are included in the Appendix.
-------
3.0 CORROSION DATA - RESULTS AND DISCUSSION
The corrosion damage data are listed in the following sections for the
different materials exposed under this program. In addition to the weight
loss data, the integral corrosion rate V-, which is defined as:
V^t) =f^ tan a, (1)
has been calculated from the weight loss Am per sample area A as a function
of time t. The true, differential corrosion rate V . is defined as:
Vd(t) = = tan B. (2)
Figure 3 serves to explain the definition of both corrosion rates. If a suf-
ficient number of data points are collected, V, can be obtained as the tangent
of the Am - time t curve as shown in Figure 3. In the present program, data
points are available only for 3, 6, 12, 24 and 30 month periods which makes
an accurate determination of V,-data difficult. However, it is possible as
discussed by Bohnenkamp, et al . (6), to calculate V, -values from experimental
V^-values provided that V. can be expressed as:
= kfn (3)
where 0 <_ n <_ 1 . A value of n = 0.5 indicates that the corrosion rate is
determined by diffusion of species involved in the corrosion process such as
oxygen through the corrosion product layer.
From Eqs. (1) and (3) one finds for the weight loss per unit area Am:
Am = Vt) - t = kt1-n (4)
-n
and by differentiation according to Eq. (2):
Vd(t) == k(l-n)t- (5)
= (l-n)Vi(t) (6)
-------
According to Eq. (6) the two functions V.(t) and V,(t) differ only by the
factor 1-n. The experimental weight loss data have been converted to V-(t)-
data and in some cases the factors n and k have been determined. The atmo-
spheric corrosion behavior of a material is characterized by the two empir-
ically determined factors k and n.
3.1 GALVANIZED STEEL
The weight loss data for the four sets of galvanized steel are recorded
in Table 3. For the first and second sets of galvanized steel and weathering
steel, 3, 6, 12 and 24 month data have been obtained. For the first set only,
30 month data are also available. For the third and fourth sets, 3, 6 and
12 month data have been obtained. For the third set, 15 month data are
shown in Table 3 which are the result of removal of the wrong samples in
July 1976. For the fourth set, only 21 months had expired when exposure
ended in April 1977.
Some of the data of Table 3 are plotted in Figures 4 and 5. The results
for the first set in Figure 4 show that after 30 months the weight loss was
the highest at site #108 and the lowest at site #120. Assuming linear
behavior between 6 and 30 months (constant corrosion rate) the differential
corrosion rate is seen to fall between 1.04 and 0.84 ym/yr (Figure 4).
Weight loss can be converted to change of coating thickness based on the
3
density of zinc (7.13 g/cm ) using:
-m +' - = Ad (ym/yr),
where Am is the weight loss per panel in grams and t the time in years. The
integral corrosion rates in Table 4 can be converted into changes of coating
thickness as:
2 v
100 ug/cm month =1.68 pm/yr
The weight loss data in Figure 5 for the four sets exposed at site #103
show the effect of the time of the year at which galvanized steel is first
exposed on the corrosion rate during further exposure. The highest weight
loss is observed for the samples which had been first exposed in October
1974, while samples exposed in April and July 1975 had the lowest weight loss.
-------
The data in Figure 5 also show that there is a slight decrease of corrosion
rates with time for the first two sets.
The curves extending to 36 months in Figure 5 have been constructed using
Eq. (4) and the appropriate n and k values which have been obtained in logAm-
log time plots as shown in Figure 6 for site #103. The n and k values for the
four sets at all sites are listed in Table 5, which shows the interesting
results that n is the highest for the first two sets and approaches zero
for the third and fourth set. A value n = 0 indicates corrosion without film
formation at a constant corrosion rate. The constant k, which is equal to
the integral corrosion rate expressed in units of weight loss per month, is
also larger for the first and second set. The combined influence of n and k
leads to initially higher corrosion rates with film formation for the first
two sets with corrosion rates approaching those of the third and fourth
set at longer times. The total weight loss Am and true, differential cor-
rosion rates for 36 months can be calculated by extrapolation using Eq. (4)
and Eq. (5) for the data in Table 5. For sites 103 and 112 one obtains:
Site 103 Site 112
2 2
Am(mg/cm ) V .(ym/yr) Am(mg/cm ) V . (ym/yr)
1st Set 1.91 0.70 1.88 0.79
2nd Set 1.89 0.72 1.59 0.64
3rd Set 1.49 0.60 1.26 0.57
4th Set 1.49 0.62 1.44 0.68
The integral corrosion rate data (V.) in Table 4 have to be multiplied by
the factor 1-n to obtain the true, differential corrosion rates V,. For the
data in Figure 4 these values fall between 0.79 and 0.64 ym/yr. Corrosion
rates obtained in St. Louis, Missouri in 1967 and 1968 in the Interstate
Surveillance Project (7) were between 2.4 and 6.0 ym/yr. The k-values in
Table 5 correspond to the weight loss after one month and are an indication
of the corrosivity of a test site. For the first exposure at site #103 in
October 1974, k = 0.135 mg/cm2 (2.27 ym/yr), while k - 0.071 mg/cm2 (1.19
ym/yr) for first exposure in July 1975.
Integral corrosion rates V. listed in Table 4 are plotted in Figure 7
for the four sets of galvanized steel. As observed for site #103 in Figures
-------
5 and 6, V,-values decrease with time at all test sites. This effect is
especially pronounced for the first and second set. Corrosion rates are in
general the highest for the first set (first exposure in October 1974) and
the lowest for the third set (first exposure in April 1975). The highest
V,-values are found at site #122 after 3 months for the first set (1.51 ym/yr)
followed by site #105 (1.24 ym/yr) and site #103 (1.20 ym/yr) after 3 months
for the second set. The lowest V,-values were observed at site #112 after
6 months (0.51 ym/yr) for the third set. This range of corrosion rates
assigns a degree of corrosivity of 3 (0.1 to 1.0 ym/yr) on a scale of 5 as
defined by Barton (8) to all test sites.
3.2 WEATHERING STEEL
The weight loss data for the four sets of weathering steel are listed in
Table 6. Figure 8 shows the weight loss data for the first set of all nine
test sites as a function of time. After 24 and 30 months the highest weight
loss is observed at site #122, while the weight loss is the lowest at site
#105. There is a pronounced decrease of corrosion rates with time as shown
in Figures 8 and 9 and, as observed for galvanized steel, the weight loss is
higher for the first and second sets. The curves in Figure 9 have been con-
structed using Eq. (4) with the values of n and k listed in Table 7, which
have been determined in logAm-log time plots as shown in Figure 10 for site
#103. While the average value of n is close to 0.5 for the first three sets,
indicating a diffusion controlled mechanism, n « 0.6 to 0.7 for the fourth
set at all sites. A larger value of n indicates a stronger decrease of
corrosion rates with time (Eq. (5)) and suggests that a more protective film
is formed upon exposure in the summer.
Integral corrosion rates V- are listed in Table 8 and plotted in Figure
11, which shows again the pronounced decrease of corrosion rates with time.
The highest corrosion rates were found for the first three months of the
fourth set which was first exposed in July 1975. The highest V^-values
occurred at sites #103 and 108 (70.1 ym/yr) followed by site #122 (64.1 ym/yr)
after 3 months for the fourth set. The lowest integral corrosion rates were
observed at sites #105 (11.0 ym/yr) and #120 (12.2 ym/yr) after 30 months for
the first set and site #105 (11.6 ym/yr) after 21 months of the fourth set.
The true, differential corrosion rates (Table 9) as calculated according to
8
-------
Eq. (5) fall between 32.4 ym/yr for site #115 after 3 months for the second
set and 2.3 pm/yr for site #105 after 30 months for the fourth set. The
differential corrosion rates obtained in this way contain a certain error
due to the error in the determination of n and k which assumes that all
weight loss data for a given site and set fall on a straight line in a logAm-
log t plot (Figure 10). In fact, as shown in Figure 12, a distinct pattern
is observed at all nine sites in the log V.-log time curves with different
slopes for different time periods for the first set. The decrease of cor-
rosion rates is slower in the summer months than in the winter months. For
the last 18 months, n > 0.5 for all sites.
3.3 HOUSE PAINT
Table 10 lists the weight loss of house paint (latex base and oil base)
on stainless steel for exposure periods of up to 30 months to the north and
to the south. For both paints and at all sites a higher weight loss is
observed for exposure to the south. A plot of weight loss as a function of
time (Figure 13) shows discontinuous corrosion behavior with larger slopes
for the first 3 months and between 6 and 12 months exposure. This is also
shown in Figure 13 for the integral corrosion rate V. at site #103. Table 11
and Figure 14 show the V.-data for all exposure conditions. The highest cor-
rosion rates for latex base paint are found at site #122 for exposure to north
and south, while the highest values for oil base paints are found at site #122
for exposure to north and at site #105 for exposure to south. The lowest
V.-values for latex base paints are found at site #105 after 6 months ex-
posure to the north and south. For oil base paint the lowest values are
found at sites #112 (north) and #106 (south) after 30 months exposure.
Despite the discontinuous corrosion behavior shown in Figures 13 and 14,
a determination of the parameter n is possible as shown in Figure 15 for site
#103. The value of n varies from n = 0.13 for latex base paint exposed to
the south to n = 0.31 for oil base paint exposed to the north.
3.4 MARBLE
The weight loss data for marble are listed in Table 12, while the time
dependence of the weight loss for two sites is shown in Figure 16. The
integral corrosion rates V. are shown in Figure 17 and listed in Table 13.
9
-------
The highest integral corrosion rates are found after three months at sites
#122, 115 and 120, while the lowest rates are observed after 30 months at
sites #106, 112 and 120. The decrease of corrosion rates with time indicates
formation of a protective film. The data in Figure 16 show this decrease of
corrosion rates in the early stages of exposure. Between 12 and 30 months
the corrosion rate seems to be constant; for site #122, where the highest
2
weight loss observed in general, it was about 126 ug/crn month, while for
site #106, where weight loss data are the lowest, it was found to be 107
2
ug/cm month as determined by a straight line through the data points between
12 and 30 months.
The characteristic constants n and k have been obtained for sites #103,
115 and 122 in Figure 18. Site #103 has the lowest values of n and k, while
site #122 has the highest values. The constants for site #122 have been used
to calculate a weight loss-time curve in Figure 16 according to Eq. (4). The
differential and integral corrosion rates can be calculated from the n and k
values of Figure 18 and Eqs. (3) and (5). For the three sites evaluated, one
2
obtains for 30 months (V in yg/cm -month):
' Vi Vd
#103 172 138
#115 189 134
#122 191 124
It is interesting to note that while the integral values seem to be the
lowest for site #103, the true corrosion rate Vj is the highest for site #103
due to the lowest value of n at this site.
3.5 SILVER
One set each of silver was exposed in the first and second year of this
exposure test. Samples were first exposed in mid-October of 1974. The
silver samples were evaluated by reflectance loss measurements and by electro-
chemical reduction of the tarnish film in 3.5% NaCl solution as described
earlier (1, 2). Figure 19 shows a typical potential-time curve for reduction
of the two and sometimes three types of tarnish film. The first plateau
corresponds to an oxide film, while the second arrest in the potential decay
10
-------
curve is due to reduction of the sulfide film at an applied constant cathodic
current. Figures 20 and 21 show the correlation between reflectance loss and
amount of electricity consumed for reduction of the tarnish film. The film
thickness d can be calculated using the formula:
d = kl if = k2Q ' (7)
o 2
where k, is a constant, for which a value for silver sulfide of 17.6A sec/cm
(9) was used. For a constant applied current of 20mA and an area A = 364.8
d = 0.048Q (A) (8)
2
cm , Eq. (8) can be written as:
for Q in mCb.
Most of the points for exposures of nine months or less fall close to
the straight lines in Figures 20 and 21. For longer exposure times a devia-
tion from linearity must occur with increasing film thickness since reflec-
tance loss cannot exceed 100% while the thickness of the tarnish film seems
to increase continuously. This becomes evident especially in the results for
the second year (Figure 21), where RL did not exceed 80 to 90%, while the
film thickness varied from 300 to 500A. The slope in the linear region was
similar for both sets of samples. The reflectance loss was somewhat higher
in the seond year of exposure.
As shown in Tables 14 and 15, the highest reflectance loss after twelve
months was observed at sites #115, 105 and 108 and the lowest at sites #118
and 112 for the first set. For the second set, the highest RL values were
found at sites #108, 115 and 122 and the lowest at sites #106 and 112.
3.6 ALUMINUM TENSION SAMPLES
The number ng of samples surviving as a function of time is shown in
Figure 22 for the nine test sites. Nine samples each of Al 2014 at 25 and
45 kilopounds per square inch (Ksi) and of Al 7079 at 15 and 25 Ksi had
originally been exposed. All samples of Al 7079 at 25 Ksi failed in the
first 255 days. At the lower stress level of 15 Ksi all samples failed in
less than 630 days except at site #120, where two samples remained. Time-to-
failure for Al 2014 at 45 Ksi showed much wider variations. At site #103 all
11
-------
nine samples failed in 66 days, while one sample each remained unbroken at
sites #112 and 115. Not many samples of Al 2014 at 25 Ksi failed in 30 months,
Only at sites #104 and 108 did all samples fail. At site #106 only one sample
cracked. Less than fifty percent of all samples failed at sites #106, 108,
112 and 115 (Table 16).
The shortest time-to-failure for Al 7079 at 25 Ksi was observed at sites
#105, 103 and 122, while the longest time-to-failure occurred at sites #112
and 115. Failure occurred in the shortest time for Al 7079 at 15 Ksi at
sites #122, 115 and 105, for Al 2024 at 45 Ksi at sites #103, 120 and 105,
and for Al 2024 at 15 Ksi sites #105 and 108.
3.7 NYLON
In the first year of this program new nylon samples were exposed every
month. However, no conclusive results were obtained, as only eight out of
216 samples were damaged. In most cases the cause for the damage could not
be determined. During the second year, nylon samples were exposed for three-
month intervals. Some samples showed severe damage which might have been
caused by birds. Table 17 lists the number of samples with holes and the
number of holes observed for the four sets during the second year. While
for the first set only one and for the second set only three samples out of
18 samples had shown holes, a large number of failures occurred for the
second and third set, which were exposed in January and April 1976.
12
-------
4.0 AIR QUALITY DATA - RESULTS AND DISCUSSION
Edited tapes have been received from the Air Monitoring Center in St.
Louis with quarterly averages for wind speed, wind direction, temperature,
relative humidity, ozone, NO,,, total hydrocarbons, total sulfur, SOp and
hLS for the time period between November 10, 1974 and March 31, 1977. The
data presented in this report are validated data. The wind direction data
have also been analyzed in wind rose format; however, these are not incor-
porated in this report due to the large volume of data. Simple average
values are, therefore, reported. The relative humidity (RH) data do not
seem to be correct in all cases, however, they are included for general
information.
Particulate matter data beginning with mid-January 1975 are also reported.
Values for total suspended particulates had not been available earlier while
the data for sulfate and nitrate had been available only for parts of the
test period and then not as concentrations (pg/m3).
Tables 18 and 19 list the quarterly average values for the air quality
parameters including particulate matter (Table 19). These data are also
plotted in Figures 23 and 24 for site #103 where, in general, rather high
corrosion rates are observed; for site #106 where rather low corrosion rates
but high pollution levels occur; for site #118 where corrosion rates are
intermediate but pollution levels low; and for site #122 where for many
materials the highest corrosion rates are measured. Since SOp and hLS are
not monitored at site #118, data are plotted for site #115, which shows the
highest hLS values.
The effect of seasonal variations becomes evident from Figures 23 and
24, especially for ozone and NOV (Figure 23) and total suspended particulates,
A
sulfate and nitrate (Figure 24). In the summer months, when temperatures are
high, the ozone levels are high, but the NO,, levels are low. The NO,, levels
are higher in the center of the city than in the rural areas.
13
-------
Total suspended participates showed maxima in the April/July quarter of
1975 and July/October quarter of 1976 (Figure 24a) which parallel those found
for ozone (Figure 23h). Similar results were found for sulfate (Figure 24b),
except that the 1975 maxima occur in the April/July quarter for sites #118
and 122, which are rural, and in the July/October quarter at sites #103 and
106 which are within the city. The average nitrate values (Figure 24c) have
broad maxima in the October/January 1975 and January/April 1976 quarters.
4.1 SULFUR DIOXIDE
In Table 18 the quarterly averages of the S0? concentration are listed.
Figure 23f shows the same values for sites #103, 106, 115 and 122. The S02
levels remain at low and constant values with the exception of site #115.
Upham (10) has reported mean SO- concentrations up to 130 ppb at 10 metro-
politan sites in St. Louis for the time period between December 1964 and
February 1965.
While Table 18 and Figure 23f show the average values for S0? for the
different three month periods between November 10, 1974, when the first air
quality data were available, and April 14, 1977, when the experiment was
terminated; Table 20 and Figure 25b show the average values for SO- concen-
tration for different exposure periods as calculated from the data of Table
18 for the individual quarters. For the exposure period starting November
1974, the average S02 concentration decreases during the 30 month period.
The highest values are initially observed at sites #115, 108 and 122. For
the total 30 month period, the highest average values occurred at sites #115,
106 and 108. Site #120 had the lowest SOp levels for all exposure periods.
There is a decrease in the average S0? concentration from 1974 to 1975.
Samples first exposed at site #103 in November 1974 were exposed to an
average concentration of 32.6 ppb during the first three months, while for
samples first exposed at the same site in January, April and July 1975,
respectively, the average concentrations were 11.4, 8.5 and 9.5 ppb. These
differences in initial SO- concentrations might in part explain the pronounced
effect on subsequent corrosion behavior of the time of the year when samples
were first exposed as observed especially for galvanized steel.
14
-------
4.2 HYDROGEN SULFIDE
As observed in the previous reports (1, 2) the H2S levels are rather low
except at site #115 which is close to refineries. For the time period between
July 9 and October 14, 1975 an average of 120 ppb and for the time period
between October 15, 1975 and January 14, 1976 an average of 126 ppb was
observed (Table 18, Figure 23g) at site #115. From the quarterly averages in
Table 18 it can be seen that the average hLS values exceed the detection
limit of the instrument, which was 5 ppb, only for some periods of the entire
exposure time.
The average values for the different exposure periods as calculated from
the quarterly values in Table 18 are shown in Table 20 and Figure 25c. The
most significant trend in Figure 25c might be the decrease of the HLS concen-
tration with increasing exposure time at sites #103, 105 and 108, the in-
crease at site #120 for all four sets, and the extremely high values for
site #115 starting in July 1975.
4.3 TOTAL SULFUR
The average values for total sulfur are listed in Table 18. Figure 23e
shows the data for four different sites. As discussed for SOp, the total
sulfur values were the highest between November 1974 and April 1975. The
maxima reported for S0? concentrations in New York in the winter months,
when more oil and coal are burnt, were not so pronounced in St. Louis during
the winter of 1975/1976, but can be seen for the winter of 1976/1977. It
might be significant for an explanation of the observed corrosion behavior
and the time-of-wetness data that the lowest average temperature at the four
sites shown in Figure 23c was between 5 and 6°C in 1975/1976 and between
0 and 2°C in 1976/1977.
Table 20 and Figure 25a list the average values for exposure periods
starting at four different times of the year. The decrease in the average
sulfur levels from the winter to the summer can be seen again. For the first
two exposure periods the averages decrease with increasing exposure time.
The data for site #115 reflect the very high FLS concentrations. For site
#122, where the highest total sulfur levels were initially observed, rather
low values are found for the exposure period starting in July 1975. Sites
15
-------
#112, 118 and 120 have the lowest sulfur levels for all periods.
4.4 OZONE
The changes with time of the mean ozone concentration shown in Figure
23h are similar to those for temperature (Figure 23c) with maximum values
between April and October. The ozone levels are higher at the two rural sites
#118 and 122 than at the other sites (Figure 23c and Table 18). This partic-
ular time dependence explains the changes with time of the average ozone
levels calculated in Table 20 and Figure 25d for the various time periods
starting at different times of the year. For exposure starting in November
1974 the average ozone levels increase with time for 24 months and then
decrease again for the last six months. On the other hand, for exposure
starting in April 1975, the average values decrease during the first year and
are higher again for the total 24 month period. For exposure starting in
July 1975 a minimum occurs for the six month period which covers part of the
summer, fall and winter.
It will be noted that the average ozone and SO- concentrations change in
opposite directions with exposure period due to the different time dependence
during a given year.
4.5 OXIDES OF NITROGEN
The changes of the quarterly averages with time plotted in Figure 23i
show higher values in the winter months than in the summer. Contrary to the
ozone levels, the NO., levels are the lowest at the sites which are farther
away from the city (#115, 118 and 122). For the exposure period starting in
November 1974, NOX levels exceed 40 ppb at sites #105, 106 and 112 for all
time periods (Figure 25e and Table 20), but stay below 20 ppb at sites #115,
118 and 122. Similar results are observed for the three other sets of
measurements.
The observed dependence of the NO,, concentration on the time of the year
leads to the time dependence of the average values for exposure starting at
different times of the year (Figure 25e, Table 20). For the test started in
November 1974 average values decrease with exposure time between six and
twelve months since the NOy levels are lower in the summer. For the same
reason average values increase for tests started in April and July 1975.
16
-------
4.6 TOTAL HYDROCARBON
The quarterly averages for hydrocarbon (Table 18, Figure 23j) did not
show significant changes with time or location. As shown in Figure 25f and
Table 20, the 2 ppm level is exceeded at site #105 for exposure up to 30
months and at sites #106 and 108 for 24 and 30 month periods for exposure
starting in November 1974. Similar results are found for exposure tests
starting at later dates. Sites #115, 118 and 122 have the lowest THC levels.
4.7 WIND SPEED, WIND DIRECTION, TEMPERATURE AND RELATIVE HUMIDITY
The quarterly averages for wind speed, wind direction and temperature
are listed in Table 18 and Figure 23a-c for four test sites. The wind speed
is higher in the time between October and April than in the other months.
The changes in wind direction with time of the year do not seem to be too
clear from the scalar average values reported here. More information is
available from the wind rose data compiled by the Air Monitoring Center in
St. Louis. The winter of 1975/1976 was warmer as the winters of 1974/1975
and 1976/1977.
The data reported earlier (1, 2) for relative humidity, which are based
on dew point measurements, have been revised to eliminate obviously erroneous
data. Table 18 and Figure 23d show these RH-data, which indicate that the
quarterly averages for sites #106, 118 and 122 fall into a narrow band
between 60 and 75%. The values for site #103 seem to be lower and fall
between 40 and 70%. For a detailed evaluation of atmospheric corrosion it
seems necessary to obtain daily or even hourly RH averages to explain varia-
tions in corrosion rates. The time-of-wetness data reported below become
important in this respect. Since the RH data still do not seem to be very
reliable, RH values from the International Airport in St. Louis, which have
been provided by F. H. Haynie of the EPA, are also included in Figure 23d.
These data show that the highest quarterly RH average was about 81%, while
the lowest value was about 66%.
4.8 PARTICULATE MATTER
The quarterly averages for total suspended particulate (TSP), sulfate
and nitrate concentration are shown in Table 19 and Figures 24a-c. The
17
-------
average values for the different time periods calculated considering the
number of sample days are listed in Table 21 and plotted in Figures 26a-c.
The quarterly averages for TSP and sulfate show pronounced changes with
the time of the year which are quite similar to those observed for ozone
(Figure 23h). Maxima are observed for the period from April to July 1975 and
July to October 1976 for TSP and sulfate with the exception that the maxima
occurred between July and October 1975 at sites #103 and 106. It is inter-
esting to note that the total sulfur and S02 average showed a minimum for the
July/October 1975 quarter. For nitrate (Figure 24c), maxima occurred in the
winter months of 1975/1976 and apparently also 1976/1977. The highest values
for nitrates were observed for the January/April 1975 quarter at sites #103,
106 and 122.
The averages calculated as a function of exposure time in Table 21 and
Figure 26 show that in general particulate matter concentrations are lower at
sites #115, 118 and 122. The changes of the particulate matter concentrations
with the time of the year (Figure 24, Table 19) give rise to the changes of
the average concentration with time of exposure and start of exposure (Table
21). For start in November 1974, no three month averages are available. For
TSP and sulfate, the lowest average values occurred for the six month exposure
period followed by a maximum for twelve months. For the remaining periods,
average concentrations for TSP, sulfate and nitrate decreased. For TSP and
sulfate, concentrations decreased in general with increasing exposure time
for all four starting dates, while for nitrates, where the changes of the
average concentrations were smaller, increases or decreases were found de-
pending on exposure sites and time of initial exposure.
18
-------
5.0 CORRELATION BETWEEN CORROSION AND ATMOSPHERIC DATA
5.1 INTRODUCTION
The results described below are a first attempt to relate the integral
corrosion rate to various atmospheric pollutants, duration of exposure and
other atmospheric factors. Various materials exposed at the different sites
are considered. It was postulated that the logarithm of the integral corro-
sion rate V. (Eq. (3)) for each material considered in this report is linearly
proportional to the pollutants and other corrosive atmospheric factors and
linear in the logarithm of time of exposure. The model is thus a multiple
regression model with the dependent variable being log corrosion rate and the
so-called independent variables being the atmospheric parameters and log time.
The coefficients in the model represent the marginal effects of the pollu-
tants, exposure time and other atmospheric factors. The analysis was done
for all materials except silver and Al alloys at all test sites and is pre-
sented in tabular form. Some of the apparent inconsistencies in the estimated
effect for different materials or different sets of materials are clearly due
to the interdependence of the so-called independent variables in the multiple
regression model. This situation is known as the problem of multi-collinearity.
In a subsequent analysis, one could account for near multi-collinearity
of the regression model by incorporating into the model the obvious as well
as the postulated interrelationships between the explanatory variables in the
multiple regression model. A factor analysis of the independent variables
space may be productive in identifying the near multi-collinearities. After
identification they could be removed from the analysis by appropriately de-
fining a reduced set of new variables which are not as highly correlated.
As the analysis now stands, there is a high degree of uncertainty in
the estimated regression coefficients. This makes it very difficult to de-
termine if the linearity assumptions for the explaining variables are valid.
Time and funding constraints did not permit an extensive residual analysis
19
-------
to identify distributional characteristics or multi-dimensional outliers,
Clearly, this is a task that yet needs to be done.
5.2 THE STATISTICAL MODEL
The statistical model considered for analysis is:
m
£ Vj(t)
V.(t) = kt"n 10 + e. (9)
where V-(t): integral corrosion rate
k: time independent effect on corrosion rate
n: effect of exposure time on corrosion rate
X-(t): level of the j pollutant to which the material is exposed
th
B-: coefficient of the j pollutant on integral corrosion rate
J
e.: random error
In view of the relation
Eq. (9) can equivalently be written in terms of weight loss Am,:
m
2 B,X.(t)
3=1
Am (t) = kt1"" 10 + e. (10)
The log-linear form of the model in Eq. (9) is considered to fit for the
experimental data and is given by:
m
log V.(t) = log k-n log t + S 3-X.(t) + n- (11)
1 j=1 3 3 i
where it is assumed that the random errors n- in Eq. (11) are independently,
identically distributed Gaussian Variates.
The pollutants considered in this analysis are TS, S02, hUS, (K, NO,,,
TSP, SO^ and N03> Analysis has been considered for all materials taking the
20
-------
data for all nine sites for a given test period except the stressed Al samples
and silver for which weight loss data have not been obtained. Different
statistical models have to be prepared for these materials.
5.3 RESULTS
The empirical model proposed above is fitted to the experimental data
and the effects of exposure time and the pollutant levels are determined
and tested for statistical significance which is indicated by:
F-ratio: Snedecor's F-statistic associated with the hypothesis
that all coefficients in the regression are zero.
2
R : proportion of the total variance of the dependent
variable explained by the regression.
S: standard error of residuals.
The forward stepwise regression program, BMDP2R, in the Biomedical
Computer Programs package (11) was used to analyze the data. At each step
in the analysis, that explaining variable which reduces the residual vari-
ance the most is included. Due to the problem of collinearity, it is
important to include all variables in the analysis to test the significance
of any one variable. This is because the explaining power of a particular
variable may be totally due to the fact that it is correlated with another
variable actually causing the observed corrosion behavior. If the test
matrix is not too unbalanced, the collinearity will be properly accounted
for in a multiple regression analysis and the test of the hypothesis that a
particular variable is significant will be more valid. In order that all
variables be included in the analysis, the forcing option of BMDP2R was
invoked. The explaining variables were somewhat arbitrarily divided into
three subsets:
A = {N03, S04, TSP, TS, log t}
B = {S02, H2S}
C = {03, NOX>
The order of entry of the variables specified in Table 22 is dictated
by the largest reduction in residual variance criterion except that all
21
-------
variables in set A are included before any variables in sets B or C are con-
sidered and then all variables in B are included before the variables in set
C are considered. For this reason, for example, CL and NOX are always the
last two variables entering the regression. CL enters before NO,, because
it causes a larger reduction in the residual variance than NCL.
Table 23 shows the results of the significance tests concerning the
effects of each of the explaining variables. In particular, the hypothesis
that the true regression coefficient of each of the variables log t, TS,
S02, H2S, 03, NOX, TSP, SO^, N03 is zero is being tested in the multifactor
environment including all variables simultaneously. It can be seen from
Table 23, that in every case except galvanized steel/set 1 and Latex the
time effect is real (greater than 95% confidence). In the case of Latex,
North, corrosion is being explained primarily by the TS, SCL, and HpS
variables. For Latex, South, corrosion is correlated with TS, SOp, 0.,, NOX,
TSP, and SO.. For galvanized steel/set 1, the corrosion rate is primarily
correlated with TSP and NOy.
5.3.1 Galvanized Steel
For galvanized steel, time of exposure and NO., had the most important
effects, NO., being an accelerating factor (Table 22a). NOY seems to have the
o A
least effect for the first set, which might be due to collinearity between
NO., and NO.,. For the second and fourth set 0- was considered last. TS and
TSP were considered third and fourth in the first set followed by the other
sulfur containing pollutants. The effect of sulfur pollutants seems to be
spread over the compounds which make it impossible at this stage of the
analysis to determine the role played by the different sulfur pollutants.
5.3.1.1 First Set
a, Explaining variable: time of exposure t
log V(t) = 1.977 - 0.144 log t; F] 22 - 16.885,
R2 = 0.4342, S = 0.0471
22
-------
3, Explaining variables: t, TS, TSP, NCL
log V(t) = 1.568 - 0.048 log t + 0.003 TS
+ 0.001 TSP + 0.024 NO-
o
F4 19 = 13.416, R2 = 0.7385, S = 0.0345
Y, Explaining variables: t, TS, TSP, ML, H^S, SO.
log V(t) = 1.557 - 0.045 log t + 0.003 TS
+ 0.004 H2S + 0.001 TSP - 0.002 S04 + 0.028 N0
Fc ,7 = 9.269, R2 = 0.7659, S = 0.0345
b, I /
5.3.1.2 Second Set
a, Explaining variable: t
log V(t) = 1.954 - 0.178 log t
FI 13 = 28.198, R2 = 0.5508, S = 0.0528
3, Explaining variables: t, TS, S02, H2S, NOX, TSP, S04, N03, 03
log V(t) = 1.863 - 0.102 log t + 0.004 TS
- 0.005 S02 + 0.005 H2S - 0.005 03
- 0.002 NOX + 0.003 TSP - 0.008 SO.
+ 0.018 N03
Fg 15 = 9.969, R2 = 0.8568, S = 0.0369
5.3.1.3 Third Set
Due to an error in the data input for the regression analysis, which
could not be corrected, a regression analysis is not available for the third
set of galvanized and weathering steel.
5.3.1.4 Fourth Set
a, Explaining variable: t
log V(t) = 1.766 - 0.080 log t
Fn oc = 4.174, R2 = 0.1383, S = 0.0695
I ,£0
B, Explaining variables: t, TS, S02, H2S, NOX, TSP, S04, N03
log V(t) = 1.911 -0.184 log t - 0.005 TS +
0.013 S02 - 0.011 H2S - 0.004 NOX
+ 0.002 TSP - 0.022 S04 + 0.070 N03
F8 lg - 7.959, R2 = 0.7702, S = 0.0420
23
-------
5.3.2 Weathering Steel
For the first set of weathering steel (Table 22b), time of exposure, TS,
SO., and TSP were the most important pollutants, while (L and NCL, which seem
to decelerate corrosion rates, were considered last. While the coefficient
for 0., is positive for the first set, it is negative for the second and fourth
set.
5.3.2.1 First Set
a, Explaining variable: t
log V(t) = 0.822 - 0.545 log t
FI 22 = 75.879, R2 = 0.7752, S = 0.0839
3, Explaining variables: t, TS, SO^, TSP, N03> H2S, S02, NOX
log V(t) = 0.702 - 0.588 log t - 0.004 TS
+ 0.006 S02 + 0.011 H2S - 0.010 NOX
+ 0.006 TSP - 0.005 S04 - 0.001 N03
Fg 15 = 85.555, R2 = 0.9786, S = 0.0314
5.3.2.2 Second Set
a, Explaining variables: t, TS, S02, H2S, NOX, TSP, S04, N03> 03
log V(t) = 0.832 - 0.495 log t - 0.004 TS
+ 0.006 S02 + 0.008 H2S - 0.005 03
- 0.007 NOX + 0.003 TSP + 0.009 S04
- 0.027 N03
Fg 15 = 27.775, R2 = 0.9434, S = 0.0550.
5.3.2.3 Third Set
Statistical analysis not available.
5.3.2.4 Fourth Set
a, Explaining variable: t
log V(t) = 0.913 - 0.646 log t
F = 327.688, R2 = 0.9265, S = 0.0635
24
-------
3, Explaining variables: t, TS, S04, S02> H2S, NOX, TSP, N03
log V(t) = 0.719 - 0.576 log t - 0.009 TS
+ 0.016 S02 - 0.001 H2S - 0.005 NOy
+ 0.001 TSP + 0.013 S04 - 0.001 N03
FQ , = 68.735, R2 = 0.9666, S = 0.0501
a, iy
5.3.3 House Paint, Latex Facing North
For the latex base house paint (Table 22c), time of exposure was only
the fifth (exposure to north) or fourth (exposure to south) important parameter.
In both cases NO., with a large negative coefficient was chosen first, followed
by TSP and SO.. 0, which was found to accelerate corrosion, and NOV were con-
*T -J A
sidered last.
a, Explaining variable: N03
log V(t) = 1.678 - 0.040 N03
FI 22 = 9.988, R2 = 0.3122, S = 0.0671
3, Explaining variables: NOo, TSP, S04, TS, t, SO-, H?S, 0-
log V(t) = 1.279 - 0.124 log t - 0.010 TS + 0.012 S02
+ 0.008 H2S + 0.014 03 - 0.001 TSP
+ 0.008 S04 - 0.005 N03
FQ ,, = 10.215, R2 = 0.8449, S = 0.0386
o , I 0
5.3.4 House Paint, Latex Facing South
a, Explaining Variable: N03
log V(t) = 1.800 - 0.047 N03
F] 22 = 9.939, R2 = 0.3112, S = 0.0783
3, Explaining Variables: N03, S04> TSP, t, TS, H2S, S02, 03
log V(t) = 0.989 - 0.067 log t - 0.009 TS
+ 0.012 S02 + 0.002 H2S + 0.019 0,
+ 0.001 TSP + 0.008 S04 + 0.004 N03
Fg ]5 = 36.824, R2 = 0.9515, S = 0.0252
5.3.5 House Paint, Oil Facing North
For the oil base paint, time of exposure and S04 were most important
while NOy was considered last (Table 22c). This result points out a different
behavior of the two types of paints since time of exposure was much less
important for latex base paint.
25
-------
a, Explaining variables: t, S04
log V(t) = 1.234 - 0.163 log t + 0.026 SO.
F9 91 = 8.415, R2 = 0.4449, S = 0.0744
C. ,£ I
B, Explaining variable: t, S04> TS, S02> H2$, 03, TSP, N03
log V(t) = 1.274 - 0.502 log t + 0.002 TS
- 0.002 S02 + 0.015 03 + 0.004 TSP + 0.001 H2S
+ 0.018 S04 - 0.033 N03
FO -.r = 10.815, R2 = 0.8522, S = 0.0454
O, I D
5.3.6 House Paint, Oil Facing South
a, Explaining variables: t, S04
log V(t) = 1.263 - 0.098 log t + 0.021 S04
F9 91 = 5.346, R2 = 0.3374, S = 0.0699
L-lC-\
B, Explaining variables: t, S04, TS, S02, H2S, 0 , TSP, N03
log V(t) = 1.415 - 0.451 log t + 0.002 TS
- 0.003 S02 + 0.003 H2S + 0.012 03
+ 0.004 TSP + 0.011 S04 - 0.044 N03
F8 15 = 9'783' R = 0-8392, S = 0.0408
5.3.7 Marble
Time of exposure, N03 and TSP explain about 87% of the experimental re-
sults. The effect of the sulfur pollutants is obscured since it is divided
in the present analysis among the various compounds. Ozone seems to accel-
erate corrosion (Table 22d).
a, Explaining variable: t
log V(t) = 2.709 - 0.306 log t
F] 22 = 75.434, R2 = 0.7742, S = 0.0473
B, Explaining variables: t, TS, S02, HgS, Qy TSP, S04, N03
log V(t) = 2.807 - 0.507 log t - 0.005 TS
+ 0.006 S02 + 0.004 H2S + 0.010 03
+ 0.003 TSP - 0.013 S04 - 0.025 N03
FQ , = 23.151, R2 = 0.09251, S = 0.0330
0,0
26
-------
5.4 CORROSION AND POLLUTANT CODE NUMBERS
In the statistical analysis of the effects of pollutants on corrosion
rates of the different materials, no direct ranking of test sites according
to corrosivity or pollutant concentration was given. Such data could be gen-
erated by using the results of a more detailed regression analysis and taking
into account the acceleration or inhibition of corrosion caused by the differ-
ent pollutants.
In order to provide a simple survey of the ranking of the nine test sites
according to corrosion rates and pollutant concentrations, Tables 24 and 25
have been prepared in which the test sites are ranked according to the severity
of corrosion (Table 24) and amount of pollution (Table 25). The highest
corrosion rates and highest pollution concentrations are ranked as 1. For
the corrosion data, values for 12, 24 and 30 months were considered. For the
second to fourth set of galvanized and weathering steel, the corresponding time
periods were used. For the Al alloys, results for 100% failure taking into
account the number of unbroken samples were used. For the pollutant data, the
average values at the end of the four exposure periods in Tables 20 and 21
were considered. The data in Tables 24 and 25 show how the ranking of the
various sites changes with material and start of exposure. For galvanized
steel, for example, pronounced changes can occur for the four sets, while for
weathering steel the ranking of a site is more or less independent of the
start of exposure as pointed out above. As a summary of these tabulations,
Corrosion and Pollution Code Numbers have been prepared for all sites and
materials. For the Corrosion Code Number (CCN), the sequence of numbers
corresponds to the ranking of galvanized steel, weathering steel, house paint,
marble, silver and stressed aluminum alloys. The rankings for different sets
of materials or the two Al alloys at different stress levels have been combined
to give one number for each material. In the Pollution Code Number (PCN), the
sequence is S00, TS, H0S, 0_, NOY and THC. The particulate matter data of
C. c O A
Table 25 have not been considered in the PCN. In this way two six-digit
numbers have been prepared:
27
-------
CCN
336652
494431
868977
123223
779799
544518
652375
987856
211134
PCN
676644
432931
227712
355553
X6X815
111373
X9X189
782466
534297
Site #
103
105
106
108
112
115
118
120
122
Based on the CCN, sites #108 (CCN = 123223) and #122 (CCN = 211134) are by far
the most corrosive sites. For these two sites the two corresponding PCNs are
355553 and 534297, indicating average or low pollutant concentrations. On the
other hand, for site #106, CCN = 868977 and PCN = 227712 indicate low corrosi-
vity but high concentrations in S00, TS, NOV, and THC. A comparison of CCNs
L. A
and PCNs does, therefore, not show any obvious correlations between corrosi-
vity and pollution. It has to be considered, however, when comparing CCNs and
PCNs that high concentrations of some pollutants might have an inhibiting
effect on corrosion rates. Haynie and Upham (12) have concluded that oxidants
such as ozone decrease corrosion rates of steels including weathering steel.
28
-------
REFERENCES
1. F. Mansfeld, "Study of the Effects of Airborne Sulfur Pollutants on
Materials", RAPS Task Order No. 26, Contract No. 68-02-1081, One-Year
Exposure Report, Science Center Rockwell International, SC553.T026AR-1.
2. F. Mansfeld, "Study of the Effects of Airborne Sulfur Pollutants on
Materials", RAPS Task Order No. 112, Contract No. 68-02-2093, Two-Year
Exposure Report, Rockwell International, AMC7010.T0112AR.
3. R.L. Myers and J.A. Reagan, "The Regional Air Monitoring System,
St. Louis, Missouri, USA," Rockwell Air Monitoring Center, St. Louis,
Missouri.
4. F. Mansfeld and J.V. Kenkel, Corr. Sci. 1_6, 111 (1976).
5. F. Mansfeld and J.V. Kenkel, Corrosion 33, 13 (1977).
6. K. Bohnenkamp, G. Burgmann and W. Schwenk, Stahl and Eisen 9_3 (22), 1054
(1973).
7. J.H. Cavender, W.M. Cox, M. Georgevich, N.A. Huey, G.A. Jutze and C.E.
Zimmer, "Interstate Surveillance Project: Measurement of Air Pollution
Using Static Monitors", Air Pollution Control Office Publication No.
APID-0666, May 1971.
8. K. Barton, "Schutz gegen atmospharische Korrosion," Verlag Chemie, West
Germany, 1976.
9. W.E. Campbell and U.B. Thomas, Trans. Electrochem. Soc. 86_, 303 (1939).
10. J.B. Upham, J. Air Pollution Control Assoc. V7, 398 (1967).
11. Biomedical Computer Programs--P-Series, University of California Press,
1977, pp. 399-417.
12. F. H. Haynie and J. B. Upham, Mat. Perf. 10 (11), 18 (1971).
29
-------
FIGURE la
FIGURE Ib
FIGURE Ic
FIGURE Id
FIGURE 1. ARRANGEMENT OF TEST RACKS ON SHELTER ROOF
30
-------
<2 <
LU
LL.
O
oo
o
CM
LU
a:
ID
CD
31
-------
Am = f(t)
tan f . ME.Vd(t)
TIME t
FIGURE 3. DEF. OF INTEGRAL (V,) AND DIFFERENTIAL (V,) CORROSION RATES
(REF. 6). 1 d
-------
600-
500-
. SITE
103
400-
1
300
200
100
GALVANIZED STEEL, 1ST. SET
START 10/15/74
105 t
106 o
103 ©
112
115 A
118 A
120 v
122 »
j .._.__!__ II I 1 I I
0
24
30
t (months)
FIGURE 4. WEIGHT LOSS OF GALVANIZED STEEL , FIRST SET, AT THE NINE TEST SITES.
33
-------
2.0i-
Set 2: +
Set 3: O
Set 4:
FIGURE 5. WEIGHT LOSS FOR FOUR SETS OF GALVANIZED STEEL AT SITES #103
AND 112.
34
-------
looor
GALVANIZED STEEL
Site #103
1st X
Set
100
CD
10
I
12 15
21 24 30
t(months)
FIGURE 6.
LOG-LOG PLOT OF WEIGHT LOSS OF GALVANIZED STEEL AT SITE #103 AS A
FUNCTION OF TIME.
35
-------
^^d Jz
trsd ,£=
O ro_J__l_4__l_
o
CO
O O
CM
r-UlH «-
^cxjI I
U3 1 . . I
*"I ' ' '
80
U3
CM^-H I
t CM 1 I
~~" I ' ' ' '
O O
o u>
CO o-
csi -a-"
cxj~
UD-
CD O o
J L
o
o
o
10
UJ
I
oo
Q
UJ
CD
u_
O
00
I
UJ
OO
at.
O
U-
UJ
t/1 cn
O UJ
C£ t
CC. t-<
O OO
o
C3
UJ UJ
C£
u.
s °
uio/6rt)-L/\
36
-------
WEATHERING STEEL, 1st Set
18 24
t(month)
30
FIGURE 8. WEIGHT LOSS OF WEATHERING STEEL, FIRST SET, AT THE NINE TEST SITES.
37
-------
E
^
E
WEATHERING STEEL
Site 1112
t(months)
FIGURE 9. WEIGHT LOSS OF FOUR SETS OF WEATHERING STEEL AT SITES #103 and 112.
38
-------
10
=
o
Set
1st x
2nd +
3rdO
4th
WEATHERING STEEL
Site # 103
k = 9.5 mg/cm
I i
12
t(months)
24 30
FIGURE 10. LOG-LOG PLOT OF WEIGHT LOSS OF WEATHERING STEEL AT SITE #103 AS A
FUNCTION OF TIME.
39
-------
.p
=)-
OJ
oo
(U
+->
oo
CO
o
00
LU
oo
I
oo
LU
I
CO
CJ3
O
oo
h
LU
oo
a:
n)
o
U-
00
OO
O
Of
o:
o
o
CJ3
LU
I
z.
ui3/6iu)
40
-------
10
iin~
o
E
E
O
1.0
1.0
10
Site #
rr~|
1st Set
Apr. Oct. Apr.
I I I
n = 0.5
10
t (months)
100
FIGURE. 12. LOG-LOG PLOT OF INTtGRAL CORROSION RAITS FOR Ttll HRSI Sl.T 01
WEATHERING STEEL AT ALL TLST SITES AS A FUNCTION Of TIME..
41
-------
1-15 4-15 7-15 10-15 1-15 4-15 7-15 10-15
FIGURE 13. WEIGHT LOSS AND INTEGRAL CORROSION RATES FOR HOUSE PAINT AT
SITE #103.
42
-------
o
00
o
CM
ll
1
I '
1
',
1 1
1 «_ ;
'
',
, i
1 |
'
,
|1
.
,'
'i
C -
{. ... ..
.
t
,"
v
o
UJ
co
UJ
UJ
OO
:D
o
co
LU
co
O
a:
OL
o
o
I
--t
43
-------
100
CT1
10
HOUSEHOLD PAINT
Site * 103
n = 0.13
6 12
t(months)
24 30
FIGURE 15. LOG-LOG PLOT OF WEIGHT LOSS OF HOUSE PAINT AT SITE #103 AS A
FUNCTION OF TIME.
44
-------
Marble
2.0
1.0
01
s
Site #122
O Site #106
-Calculated (Eq.4)
mg/mo
39 mg/mo
12
18
t(months)
24
30
FIGURE 16. WEIGHT LOSS OF MARBLE AT SITES #106 AND #122 OVER A
THIRTY-MONTH PERIOD
45
-------
co
UJ
GO
co
UJ
UJ
UJ
co
00
o
CO
UJ
o:
co
o
CJ3
UJ
0
o
LT)
O
o
UJ
o;
C.D
0
o
CO
O
o
0
o
(Miuoui
46
-------
2000
1000
100
Marble
Site 103: X , n=0.20, k=0.34mq/cm month
Site 115: * , n=0.29, k=0.51mg/cm2 month
2
Site 122: V , n=0.35, k=0.63mg/cm month
I
I
12
t(months)
24 30
FIGURE 18. LOG Am-LOG TIME PLOT FOR MARBLE AT SITES #103, 115, AND 122.
47
-------
co
a:
o
M CD
a: z
I -!
o a:
LU rs
_i a
LU
co
u_ LU
o i
ii
I CO
>I LU OO
u_ o
z z
3C < O
co i
I-H OS
o
o
II
O
Q
LU
0£
O
ii
ca
o
3C
i
ct
o
a: DC
co
z ii
LU Z
LU a:
LU
CO LU
- Q LU
3= LU a:
CO OC Z3
z oo
o o o
I1 f_ Q.
I X
eC Q LU
_JliJ
LU CO U.
QL 33 O
cr> o
i CM
LU LU
a: a:
ro ZD
CD CD
ii ii
LI- U-
(30S
48
-------
0_
o
o<
O
O
O O
'z:
o
>- o
I UJ
I 1 oo
o
i-c CD
O OL
UJ ^3
_l Q
LU
CO
U. UJ
O I
o 2:
s: >-H
< z
Q I
2: =a:
uj oo
o
u_ u_
LU
C£. 3C
oo
z: ii
uj z:
UJ CXL
\~ H- uj'
uj ce
CQ uj r>
cj oo
CL ZD O
>-H Q Q.
3; uj x
oo a: uj
o o u_
-> \- O
«a: a a:
i LU
-------
o
§
CO
O
UJ
oo
on
o
o
2:
o
p
o
Ll_
<:
oo
O
CM
^ §
ce:
Z3
00
00
LU
oo
o
II
oo
LU
o
o
OL
CO
CM
CM
O
CD
50
-------
LT>
O
O
O
O
LU
to
or
o
o
o
oo
=c
oc
co
oo
o
H- 4
CO
LU
t
ce
LU
Q.
CM
CM
LU
Qi
C3
O
o
o
IT)
O
O
51
-------
o
o
o
o
=tt=
z
ID
U_
-------
CO
o
o
o
"^ o
CO
o
O
o
II
I
o
co
co
UJ
i
Q-
CO
O
ii
co
UJ
-------
o
o
C\l
=8=
o
LU-
LU
o
ii
K-
-------
r
o
o
LD
CO
o
U_
LiJ
2:
ii
I
U_
O
o
II
I
o
eC
=C
o
o
0 5
2 §
o:
C/5
to
UJ
_l
O-
-------
00
a;
o
\
\
o
z.
o
I\
I
o
z.
=D
u_
CD
o
o
56
-------
\
o
C\J
o
CD
O
in
o >~
2 §
O
CM
UJ
I
fI
GO
CfL
O
u_
UJ
tI
I
u.
o
z
o
II
I
o
2:
=>
u.
et
OO
C3
o:
r>
oo
oo
<
oo
O
H-t
oo
ct:
UJ
Q-
CM
CM
UJ
oc
en
o
o
o
un
57
-------
o
o
C\J
c\j
o
u_
UJ
s:
i<
i
LJ_
o
z.
o
It
I
o
2:
*
o
c
CD
a:
oo
oo
uu
U-
o
CJ
oc.
o
o
o
LT>
CM
CVJ
DC
ZD
CJ3
o
o
58
-------
O
OL cc:
(O
CO
59
-------
c
o
Q
T3
01
-»-J
u-,
x O +
LU
CO
n: c\j
I c\j
ce: *~
O Q
O) 00
T3 i
O <
1 1 1 *
C£ 00
t-H O
Q
CO
CTl
o
2:
I
OO
C\J
Qi
Z3
-------
CTl
CQ
C\J
O)
-o
UJ i
o;
00
o
Q-
s: oo
UJ LlJ
U-
O
00 cf
UJ r
< -
Di Q
nr z:
1
-------
'E
13
X
03
DC
0 x O +-
en
^ o
LU
LU
CO
LU
CM
Q£ CM
O i
Lu
O
>- I
( r
II
Q "
ii {&
5! O
LU OO
> O
t I I
h- =«=
*£.
_1 CO
LU LU
o: i
i i
LJ_ oo
00
LU
CTl
O O
s: on
i <
D; Q
T3
00
CM
O
O
62
-------
O
01
CQ
LU
rc
C£ CM
C5 C\J
U_ i
JO Z
a.
-co
r
rV r
CO
"CD
T^~
<: r^
CTl
CD i
CO
LU
LU
cc:
ai
ro
(XI
LU
a;
ID
CD
IH
Lu
63
-------
CN
O
(f)
o
CJ
o
OJ
0 X
CTi
O
UJ
co
I CM
CSJ
o: r
O
U_ Q
O-LO
O-i
Q tD
ii O
X i
O
I I *
Q CO
O
OL
00
CO
u-
O
oo
co
Q£ O">
UJ i
5^
m oo
h-
O CJ
S o;
uj 2:
UJ
3: z.
CO
CVJ
ai
-^>
CD
(qdd)
64
-------
(S)
CN
o
(N
O
CS
cr>
QQ
CXL CVJ
O OJ
-Q Z
Q.- L4J
-3L t
i i
u_ oo
oo <:
UJ
CD r-^
§ CD
=C "
3: co
LU
o;
en
co
CM
LU
QL
65
-------
O
-------
X
o
r-.
01
o
CQ
LU
CC
O
--- OJ
-Q I
Q.
Q.Q
UU CO
CD
O r-
CC
I >
ii V£>
Z O
O >
OO
oo o
LU i
Q =«:
ii
x co
O UJ
o co
CO I
LU <;
C3
LU
> r
<
f%
z: i
i oo
O 3T
2: o
t
oo
C\J
(qdd)
67
-------
(J
I
o
O>
-t-J
I/I
o +
I
en
o
CO
UJ
Si
O CM
U- CM
00
O ^
CO
C£ "
< 10
o o
O r
o:
Q -
>- CO
n: o
_i =tt=
-------
CO
Cd Ovl
o oj
^ £
e[
OO »
LU IQ
(_ O
d-
CM
o
o
69
-------
Q
01
LU
1C CXI
H- CM
CO
CD
O
u_ oo
I O
oo =«=
LJ- oo
O UJ
I
CO i i
LU oo
CD
< I
01
O r
s: oo
i
uj in
LlJ C_)
ct: o:
CM
70
-------
CTl
03
M
CU
LU
c\j
-------
Months
60i- 6 24
n 31230
40
20 -
m.
START JULY 1975
f I I fll
TS
in m ill
40-
20
START APRIL 1975
0
60
40
20-
Iff
Ttff 1 I
03
D-
O-
START JANUARY 1975
JUI
m M
60-
40
20
START NOVEMBER 1974
ll
Mfl
103 105 106 108 112 115 118 120 122
SITE f
FIGURE 25a. AVERAGES OF TOTAL SULFUR (ppb) FOR DIFFERENT EXPOSURE LENGTHS
AND START OF EXPOSURE.
72
-------
40-
20
40-
~ 20
CO
40
20
40
20
Months
6 24
SO-
START JULY 1975
1 if f f
START APRIL 1975
START JANUARY 1975
1
START NOVEMBER 1974
J
f
103 105 106 108 112 115 118 120 22
SITE it
FIGURE 25b. AVERAGES OF SULFUR DIOXIDE (ppb) FOR DIFFERENT EXPOSURE
LENGTHS AND START OF EXPOSURE.
73
-------
CO
Q-
Months Hob
6 24 *-
31230
16
12
Q
o
4
0
16
12
8
4
0
16
12
8
4
0
16
12
8
L
n
- vaiL START JULY 1975
k |
1
T
- y
[1
-
-
~~ ^^
- f]
j
J
TIT
-
II
START APRIL 1975
fl
Hi
If T
I
START JANUARY 1975
_
--
1
"T
1 TT
f u
START NOVEMBER 1974
irf i
III T^
_.
nil!
103 105 106 108 112 115
SITE f
118 120 122
FIGURE 25c. AVERAGES OF HYDROGEN SULFIDE (ppb) FOR DIFFERENT EXPOSURE
LENGTHS AND START OF EXPOSURE (DATA FOR SITE #115 NOT SHOWN
WERE OFF SCALE, SEE TABLE 20, III.)
74
-------
Months
6 24
31230
inn
40r
START JULY 1975
20- T
START APRIL 1975
40
20
40
20
0
40
20
START JANUARY 1975
START NOVEMBER 1974
i
I
103 105 106
08 112
SITE
70
//
FIGURE 25d. AVERAGES OF OZONE (ppb) FOR DIFFERENT EXPOSURE LENGTHS
AND START OF EXPOSURE
75
-------
20i
20
UJ
CJJ
40
20
40
20
Months
6 24
"i.1.2.30
NO,
START JULY 1975
START APRIL 1975
START JANUARY 1975
r
START NOVEMBER 1974
103 "105 106 108 112 TI5 1T8~" 120 "122
SITE 4
FIGURE 25e. AVERAGES OF OXIDES OF NITROGEN (ppb) FOR DIFFERENT EXPOSURE
LENGTHS AND START OF EXPOSURE.
76
-------
0.
o
Months
6 24
31230
THC
START JULY 19/
-------
Q
Q_
(/)
00
CD
LU
o;
ZD
oo
o
D_
X
LU
LU
U_
LL.
II
o
o
U_
T>
E
cn
oo
LU
«=c
1
o
II
I
D-
Q
O.
00
«a: o:
I ^D
o oo
h- O
Q-
Lu X
O LU
OO U_
LU O
o
< h-
o: o:
LU <;
> i
-------
03
D
C/5
-D
I
a:
CO
UJ
39VH3AV
LU
OL
O
Q.
X
oo
(E
z:
UJ
to
o
Q-
X
Q
O
O
CO
oo
u.
o
UJ
CJ3
UJ
<
OJ
UJ
o:
CD
II
u.
79
-------
B
CD
F=
o;
i
co
o
ex.
X
-------
Table 1. Materials, Preparation, Exposure Conditions
and Assessment of Corrosion Damage
Material
Galvanized Steel
(4" x 6" x 0.036")
Weathering Steel
(Corten A)
(4" x 6" x 0.036")
AT 7079-T651
(tension specimen
in short trans-
verse direction,
15 and 25 Ksi
stress level)
Al 2014-T651
(tension specimen
in short trans-
verse direction,
45 and 25 Ksi
stress level)
House Paint
on stainless steel
(4" x 6" x 0.036",
type 3 with 2B
finish)
a. oil base,
2.5 mil.
b. latex, 1.5 mil
White Cherokee
Marble
(4" x 6" x 3/8")
Silver
(6" diameter
plated discs)
Textile-Nylon
[15 denier nylon
filament)
Exposure Condition
30° from horizontal
facing south
30° from horizontal
facing south
30° from horizontal
facing south
30° from horizontal
facing south
Vertical facing
north and south
30 from horizontal
facing south
Open to ambient
air but protected
from direct environ-
mental factors
Horizontal, no
protection
Sample Preparation Assessment
Degrease, clean,
weigh
Gravimetric
Degrease, descale, Gravimetric
weigh
Degrease, stress
Degrease, stress
Degrease, clean,
apply paint,
condition, weigh
Clean, condition,
we i gh
Degrease
Stress and mount
,on plastic slide
Time-to-
failure
Time-to-
failure
Gravimetric,
loss of
reflectance
Visual, gra-
vimetric
Visual, loss
of reflec-
tance, electro-
chemical
Visual in-
spection for
defects
81
-------
Table 2. Air Quality Data Used for This Project
Parameter Code
Wind speed (m/sec) WS
Wind direction (degrees) WD
Temperature (°C) TEMP
Ozone concentration (ppb) OZONE
Total hydrocarbon concentration (ppm) THC
NOX concentration (ppb) NOX
Total s-ulfur concentration (ppb) TS
H2S concentration (ppb) H2S
S02 concentration (ppb) S02
Relative humidity (%) RH
Sulfate (yg/m3) $04
Nitrate (yg/m3) NOa
Total Suspended Particulates (yg/m3) TSP
82
-------
Table 3. Weight Loss of Galvanized Steel (mg)
1st Set. Start 10-15-74
Site
103
105
106
108
112
115
118
120
122
Site
103
105
106
108
112
115
118
120
122
3 Months
82.3 +0
63.7 + 0
63.3 + 1
79.6 + 1
58.6 + 5
70.2 + 3
54.7 + 0
62.1 + 7
88.6 + 0
6 Months
.1 159.2
.2 144.5
.4 123.2
.3 151.0
.2 123.5
.1 128.4
.5 120.4
.9 111.9
.7 133.2
3 Months
85.4
85.9
67.8
64.1
65.5
62.2
67.3
58.8
50.5
+ 3.6
+ 5.8
+ 3.2
± !-7
+ 0.3
± 2-7
+ 4.2
+ 2.8
+ 0.1
± °-
± 5-
± °-
± °-
± 1-
± l-
± 5-
± !
± 2-
2nd
6
130.
139.
111.
124.
111.
111.
106.
98.
104.
1
a
9
1
8
6
6
6
3
Set,
12 Months
264.9
273.4
234.3
266.6
217.2
242.1
212.9
192.8
229.3
Start
Months
5 +
7 +
6 +
6 +
9 +
1 +
7 +
8 +
3 +
11.9
9.4
2.1
3.0
0.6
3.7
2.5
0.4
1.0
+ 0.5
+ 0.6
± 7-2
+ 0.2
+ 3.8
± 2-1
+ 8.0
+ 0.7
+ 2.2
1-15-75
12
244.6
230.3
192.0
220.8
194.5
208.6
186.7
198.8
204.0
24 Months
431.7 +
464.0 +
406.8 +
497.2 +
412.7 +
425.8 +
379.7 +
387.6 +
471.6 +
Months
+ 6.1
+ 3.3
± 7-4
+ 3.8
+ 5.0
+ 12.6
+ 2.6
+ 0.1
+ 7.5
4.9
2.6
12.2
1.2
2.3
0.4
9.8
11.2
0.2
24
395.
439.
351.
421.
356.
363.
364.
342.
410.
30 Months
510.
558.
499.
619.
489.
526.
481.
461.
590.
0 + 3.
9 + 4.
9 + 0.
0 + 5.
9 ± 6.
3 + 6.
1 + 2.
5 + 6.
7 + 8.
2
1
4
4
5
6
4
3
3
Months
3 +
1 +
7 +
5 +
9 +
6 +
0 +
6 +
4 +
13.1
0.8
0.5
5.6
0.1
2.2
1.5
2.1
0.5
83
-------
Table 3 (Continued)
3rd Set, Start 4-15-75
Site
103
105
106
108
112
115
118
120
122
Site
103
105
106
108
112
115
118
120
122
3 Months
59.7 + 1.5
45.0 + 1.6
39.5 + 2.7
50.5 + 0.1
36.6 + 0.2
54.5 + 1.7
41.4 + 0.6
34.5 + 1.1
50.3 + 1.7
3 Months
49.6 + 1.3
52.4 + 0.3
39.2 + 1.4
59.2 + 0.7
37.5 + 2.2
48.0 + 4.9
45.1 + 3.0
36.2 + 1.2
60.9 + 4.0
6 Months
93.6 + 1.0
77.2 + 0.7
71.5 + 1.7
86.6 + 1.4
72.5 + 3.4
77.7 + 2.0
71.0 + 0.5
59.5 + 0.6
88.6 + 6.4
4th Set, Start
6 Months
101.6 + 2.7
98.5 + 5.0
73.0 + 2.6
109.4 + 4.9
76.9 + 1.6
105.1 + 1.6
100.9 + 3.0
76.0 + 1.2
125.9 + 2.3
12 Months
180.3 + 0.8
146.2 + 1.2
128.5 + 0.1
173.0 + 1.4
129.7 + 2.7
155.4 + 1.0
143.0 + 8.0
118.1 + 1.8
177.3 + 14.7
7-9-75
12 Months
192.6 + 5.8
176.5 + 2.7
143.4 + 1.8
188.9 + 12.8
155.8 + 12.1
193.6 + 2.9
195.6 + 21.6
149.9+ 5.5
234.4 + 11.2
15 Months
216.8 + 2.8
197.5 + 2.9
168.7 + 3.6
225.4 + 2.4
170.7 + 1.3
199.1 + 1.6
196.2 + 0.0
165.4 + 1.2
242.8 + 16.8
21 Months
289.7 + 1.1
300.0 + 3.9
264.7 + 0.7
328.2 + 0.5
254.3 + 3.3
287.0 + 0.4
289.9 + 13.0
263.6 + 4.6
300.1 + 14.8
84
-------
Table 4. Integral Corrosion Rates Vj (yg/cm2 month) for
Galvanized Steel (Area = 3iO cm2)
1st Set. Start 10-15-74
Site
103
105
106
108
112
115
118
120
122
3 Mo.
Note:
89
68
68
85
62
75
58
66
95
100
.4
.4
.1
.5
.9
.5
.7
.8
.2
yg/cm
6 Mo.
85
77
66
81
66
69
64
60
71
month .
.5
.7
.1
.3
.5
.0
.8
.3
.6
V
=:
2nd
Site
103
105
106
108
112
115
118
120
122
3 Mo.
91.
92.
72.
69.
70.
66.
72.
63.
54.
9
2
9
0
3
8
3
2
2
12
71
73
62
71
58
65
57
51
61
Mo. 24 Mo. 30 Mo.
.3 58.1 55.8
.2 62.3 60.0
.1 54.8 53.9
.6 66.8 66.5
.4 55.5 52.6
.2 57.1 56.5
.1 51.0 51.6
.9 52.3 49.7
.6 63.5 63.5
1 . 68 ym/yr
Set,
Start
1-15-75
6 Mo.
70
75
60
67
60
59
57
53
56
.3
.2
.0
.1
.3
.7
.4
.2
.1
12 Mo. 24 Mo.
65.8 53.2
61.9 59.0
51.6 47.4
59.4 56.8
52.3 48.1
55.2 48.7
50.3 49.0
53.5 46.1
54.8 55.2
85
-------
Table 4 (Continued)
3rd Set, Start 4-15-75
6 Mo. 12 Mo. 15 Mo.
J 1 1C
103
105
106
108
112
115
118
120
122
64.2
48.4
42.6
54.2
39.4
58.7
44.5
37.1
54.2
50.3
41.6
38.4
46.5
39.0
41.9
38.1
31.9
47.7
48.4
39.4
34.5
46.5
34.8
41.9
38.4
31.6
47.7
46.8
42.6
36.1
48.4
45.2
42.6
42.3
35.5
52.3
4th Set. Start 7-9-75
3 Mo. 6 Mo. 12 Mo. 21 Mo.
*J t **w
103
105
106
108
112
115
118
120
122
53.2
56.5
42.3
63.5
40.3
51.6
48.4
39.0
65.5
54.5
52.9
39.4
58.7
41.3
56.5
54.2
41.0
67.7
51.9
47.4
38.7
50.6
41.9
51.9
52.6
40.3
62.9
44.5
46.1
40.6
50.3
39.0
44.2
44.5
40.6
46.1
86
-------
oo
-a
a>
N
re
CD
O
M-
oo
-a
s-
o- E
o
c
o en
t/i
o c
s- -r-
s_
O -^
LO
a>
oo
c
o
o
a>
^
O)
.1;
oo
t i
o
o
LO
o
0
o
t (
o
CM
r 4
O
oo
CM
O
LO
OO
O
CM
O
oo
o
i 1
00
to
0
o
0
I 1
o
0
LO
o
o
0
o
1 1
o
r-l
CM
o
o
0
oo
i4
o
LO
o
0
o
oo
o
o
o
LO
o
0
oo
r4
o
oo
CO
o
0
CM
CM
o
o
o
OO
4
o
o
, 1
o
to
0
o
r 4
1 1
o
CM
o
o
00
0
o
o
o
o
r 1
o
o
0
I 1
I 1
o
00
o
i4
o
o
o
0
o
o
CM
o
o
LO
0
0
r 1
00
o
0
r 1
0
OO
§
o
00
r-4
o
CM
< 4
r-4
LO
0
o
CM
T 4
o
CM
o
o
o
o
o
01
N.
o
o
<l
o
00
o
0
oo
1 I
o
LO
T-4
t 1
oo
00
o
o
OO
o
0
o
o
i4
o
o
C-»
oo
o
o
.4
o
r-,
00
o
0
r-4
o
CO
II
r 4
oo
o
o
CM
o
o
f-
oo
o
o
00
o
o
r--..
0
o
t 4
o
0
0
CM
T I
o
o
CM
r-4
§
o
CM
o
0
OO
LO
o
o
0
o
o
LO
LO
o
o
o
0
o
en
0
o
I--
o
o
CM
CM
LO
o
0
CM
rH
o
?l
LO
o
?l
OO
1 1
o
?l
LO
0
?l
i4
0
?l
LO
o
?l
CM
r-4
o
?l
oo
o
o
s-
<0
(U
00
LO
o
+J
o
a.
in
a>
o
a
CM
en
o
ii
a>
o
87
-------
CD
O)
OO
en
s-
Ol
.C
4->
rd
CD
01
O
cn
cu
LO
CO
03
^J.
f^
cn
r-H
LO
r-H
S-
O)
0
u
0
.,_>
^_
(O
oo
1
^_J
Ol
OO
^_)
10
s*.
u.
l/»
-C
c
o
0
co
JC
c
o
^f.
CM
»
,i_
c
o
2:
CM
1 1
(/>
-M
c
o
^
LO
LO
JC
-rJ
S
CO
£
r-
oo
co
rt
LO
+ |
VO
LO
cn
cn
LO
r^
CO
r-H
+ 1
*
CO
cn
LO
cn
o
LO
CO
-t- 1
LO
r-H
LO
CO
CO
«*
LO
*3-
+ |
*
LO
CD
^j-
LO
CM
O
CM
+ 1
LO
,3-
r-H
CO
CO
CO
0
1
cn
cn
r-H
r-H
+ |
r-H
f^
r-H
f*^
LO
r-H
CM
CO
+ 1
CM
CO
co
LO
LO
«*
LO
i 1
+ 1
1*-
cn
t^
r-.
LO
r>-
r-H
CM
+ |
cn
co
CM
CO
CO
r^
CO
CO
+ 1
co
cn
LO
LO
CM
LO
O
> i
r^
,^
CO
+ |
O
CO
CO
LO
r**^
CM
O
^
+ |
CM
cn
cn
co
r-.
cn
LO
+ 1
^d-
0
co
co
LO
co
f^.
CM
+ 1
**
,_,
r 1
VO
CO
.*
cn
CM
+ 1
=*
CM
, 1
LO
CM
LO
O
r-H
LO
CM
^-
+ 1
cn
en
3-
r-H
O
r-H
CO
LO
+ 1
LO
cn
LO
cn
cn
r-H
oo
00
+ 1
CM
CO
LO
r-H
00
CM
en
+ 1
r^
r^.
oo
"*
cn
CO
CM
+ 1
CM
r^
LO
LO
CO
CO
o
r-H
r 1
1
CM
r-H
+ 1
CM
O
CM
LO
p>^
CM
cn
CO
+ 1
0
CM
«^
LO
r-H
LO
00
+ |
CT»
CO
^o
cn
LO
CO
r-.
CO
+ 1
CM
«-}.
O
CO
CO
CO
LO
CO
+ 1
1 1
,3-
o
LO
CM
CM
H
r-H
LO
,3.
LO
+ 1
CO
LO
CM
O
r-H
r-H
00
LO
+ 1
CM
r-H
LO
cn
cn
CM
r-H
**
+ t
co
LO
^J-
LO
LO
LO
LO
+ 1
LO
cn
LO
LO
**
CO
CO
CO
+ 1
r-H
LO
^>
r-H
CO
LO
r 1
r-H
O
O
+ |
r-H
LO
CO
r-H
cn
O
cn
^
+ 1
O
cn
CM
cn
CO
*
cn
LO
i
-^ j
co
CO
en
LO
LO
«*
0
en
+ 1
LO
o
i i
r-.
CO
co
cn
CO
+ 1
CO
r^
LO
LO
CM
CO
r-H
1
CM
CO
LO
+ |
r-»
,-j.
cn
CO
i
CM
^J.
r 1
+ |
co
cn
f*^
o
r-~
CO
CO
r-H
+ 1
LO
r-H
p-^
fs^
LO
r-H
LO
r-H
+ 1
CO
LO
r-^
^j-
CO
en
^j.
CO
+ 1
cn
LO
co
^*
CM
O
CM
i 1
r~-
^j-
LO
CM
+ 1
o
, 1
fv^,
o
<t
r-H
o
CO
cn
+ 1
CM
*j-
LO
|*s^
o
r-H
CO
OO
VO
-t- '
o
o
CM
CO
cn
i^
CM
+
CM
CO
LO
CM
"*
VO
CO
CM
+
CO
CO
r-H
cn
CM
CM
CM
r-H
88
-------
Ol
o
o
vo
0)
-Q
(O
LO
on
LO
s_
(O
3
C
to
oo
i
cu
oo
o
o
O)
00
-C
C
0
CM
o
r-l
10
-C
C
o
VO
to
C
o
CO
0)
1/5
r-~
cn
+ 1
cn
r-l
r 4
cn
CO
0
cn
+ 1
VO
r-l
00
^
s
+ 1
CM
VO
LO
VO
r 1
« 1
r 1
O
O
0
LO
CO
co
O
i
00
o
CO
+ 1
CNJ
CO
LO
CM
00
LO
+ 1
VO
00
LO
CO
00
r-l
VO
r-H
o
CM
CM
co
LO
cn
CM
o
< 1
**
00
+ 1
CM
0
oo
CM
+ 1
o
oo
CM
r-l
^
0
CM
+ 1
CM
CM
VO
CM
CO
+ 1
CM
LO
CM
VO
O
00
r-H
+ 1
vo
CM
cn
co
CM
+ 1
CM
O
VO
_,
0
^
oo
cn
=*
LO
CM
CM
+ 1
cn
LO
VO
cn
CM
00
o
r-H
O
oo
cn
co
+ 1
cn
r-H
OO
t 1
+ !
**
LO
r-H
00
LO
CM
0
r-H
+ 1
O
CO
r-H
r-H
O
CO
+ 1
VO
CO
CM
CM
r-H
r-H
VO
r-l
+ 1
vo
CM
r-H
VO
O
+ 1
cn
LO
cn
00
VO
+ 1
00
cn
i i
00
cn
O
CO
CM
OO
cn
CM
LO
r 1
I 1
r-H
r-H
r-H
+ 1
OO
CM
00
^
co
LO
+ 1
0
LO
LO
CO
vo
00
co
+ 1
CO
CM
CO
I 1
LO
+ 1
vo
o
LO
CM
00
r-H
i (
O
CM
+ 1
CO
co
VO
00
cn
+ 1
cn
co
co
vo
LO
LO
r t
co
+ 1
cn
vo
CO
O
CO
o
VO
CM
CM
CM
0
CM
r-H
LO
co
vo
1 1
+ 1
r-H
co
CM
r-H
o
I 1
o
00
VO
+ 1
r^-
LO
CO
co
co
+ 1
CO
oo
co
CM
LO
cn
vo
fv.
CM
LO
CM
CM
CM
r-H
89
-------
un
o
0
LO
to
oo
i
CD
OO
-C
c
o
LO
r-l
(/)
.E
c
o
CM
Tl
00
c:
0
LO
I/I
_C
C
o
00
d)
r-H
CM
CM
r 1
00
CTI
LO
LO
LO
+ 1
i-H
LO
LO
8
+ 1
CTi
00
LO
LO
LO
00
CM
+ 1
00
CTI
CM
OO
OO
o
1 1
LO
CO
LO
+ 1
oo
00
00
00
0
CTi
CM
CM
+ 1
LO
O
OO
^
r 1
+ 1
O
o
OO
CM
LO
0
t-H
CO
CM
+ 1
LO
LO
CM
«t
OO
+ 1
LO
1 1
o
m
LO
+ 1
CM
O
r-H
LO
LO
r-l
+ 1
LO
CM
LO
O
r-l
OO
5
LO
LO
OO
r--.
LO
^
+ 1
CTI
00
LD
CM
LO
r-l
+ 1
r 1
CO
CM
CO
LO
CM
OO
LO
+ 1
O
00
00
o
i-H
ro
LO
^
CM
CM
1
LO
CTI
CM
OO
+ 1
CM
CM
LO
CM
CM
LO
I
+ 1
OO
00
CM
LO
OO
=3-
+ 1
r-l
CM
LO
CM
CM
1
-t
O
oo
+ 1
LO
CTi
t
00
O
oo
1 1
1 1
+ 1
oo
LO
CO
LO
LO
^.
oo
+ 1
1 1
oo
OO
oo
LO
^
LO
+ 1
LO
CTi
CM
LO
II
1 1
^a-
CM
r 1
+ 1
CM
LO
1 1
LO
CM
r 1
00
+ 1
CTi
«=!
i-H
LO
CTi
CTi
+ 1
oo
r-l
5
^.
5
+ 1
CM
CM
CO
i 1
H
i 1
CTI
OO
+ 1
O
LO
LO
LO
OO
OO
OO
+ 1
OO
CTi
oo
CM
LO
CO
CTi
+ 1
0
oo
CM
O
r-l
Tl
+ 1
CO
LO
«=)
CM
O
CM
r-l
*a-
OO
V 1
^J.
1--.
II
LO
00
LO
00
OO
i 1
+
i 1
O
CTi
CM
r*-.
,-,.
LO
CM
+
CO
LO
LO
CTi
LO
00
OO
i 1
LO
OO
CM
CM
1
LO
CTI
M
S-
CO
CD
00
3
O
LOOOOi ICTlOLOOOCO
CM LO OO LO O
CTI r-H r o LO
CTi CM LO
CM CM LO
OOOOLOCMLOLOCTlCMLO
r-HCMr-tOOCOOOCTlLDCTl
I CM
OOOOCMCOOOLOOOO
LO^J-LOLOLOLOLOLOr^
C
o
O>rHCMCOOLOr-ICOi I
COLOCMr-HCTlCTlCOLDr-H
ilOOLOCMCMOLQi-HOO
C
o
OO
QJ
CM LD 00 CO CM
r-H CM LO r-l
+ 1 +1 +1 +1 +1
I r-l OO LO
I rH OO
I +1 +1 +1
OOLOiir^it^J-CMLOCM
LOCMLOLOCOOOiI O O
CMOOLOCMOCTlOO ICTl
=toooo«*oooooooooo
OO LO LO 00
oooo
CM
LO OO O CM
r-l r-l CM CM
90
-------
o>
O)
oo
en
c
o;
rO
C.
(C
-ameters r
c
^,
oo
3
Li-
CU
oo
T3
1
0)
oo
o
£
O
<_>
oo
cu
00
in
S-
u_
LO
en
LO
O
oo
^O
r-H
LO
O
OO
LD
OO
LO
O
r-H
.*: co
CO
LO
0
CM
CO
o
CO
LO
LO
o
o
LO
o
r 1
LO
CM
LO
o
co
LO
LO
o
o
LO
LO
o
o
LO
oo
o
CO
r-H
LO
0
LO ^f r-v t I i I
en Is-* co co co
^- LO ^i" *^J" CO
tO 'O LD LO 1
o o o o o
o en en co en
OO CO CO "3- LO
en oo ^j- ^* co
LO f-- LO «* LO
o o o o o
* LO co en o
«3- LO -sf ro LO
co CM LO en »-H
OO LO OO CM LO
O 0 0 O O
o co
-------
Table 8. Integral Corrosion Rates V. (mg/cm2 month) for Weathering Steel
(Area =310 cm2)
First Set - Start October 15, 1974
Site
103
105
106
108
112
115
118
120
122
Note:
Site
103
105
106
108
112
115
118
120
122
3 Months
4.10
2.87
2.81
3.84
2.69
3.38
2.76
2.62
3.14
1.0 rag/cm? mo H
3 Months
3.76
2.98
2.70
3.19
2.63
3.21
2.76
2.39
2.64
6 Months
2.91
2.06
1.94
2.57
2.05
2.46
1.99
1.87
2.29
12
Months
2.25
1.55
1.70
2.19
1.60
2.06
1.80
1.55
2.10
24 Months
1.30
0.89
0.99
1.34
1.01
1.33
1.20
0.95
1.45
30 Months
1.07
0.72
0.82
1.09
0.81
1.10
0.99
0.80
1.19
15.25 ym/year
Second Set
6
- Start
Months
3.02
2.16
2.31
2.96
2.22
2.59
2.32
1.98
2.82
January
15, 1975
12 Months
2.14
1.48
1.65
2.14
1.56
2.03
1.84
1.51
2.08
24 Months
1.23
0.84
0.94
1.25
0.97
1.23
1.11
0.91
1.36
92
-------
Table 8 (Continued)
Third Set - Start April 15, 1975
Site
103
105
106
108
112
115
118
120
122
Site
103
105
106
108
112
115
118
120
122
3 Months
3.55
2.55
2.98
4.16
2.71
3.20
2.98
2.63
3.78
3 Months
4.60
3.58
3.82
4.59
3.31
4.28
4.10
3.33
4.20
6 Months
2.99
2.01
2.74
3.13
2.43
2.87
2.59
2.29
2.93
Fourth Set - Start July 9,
6 Months
2.79
2.07
2.49
2.81
2.31
2.74
2.52
2.24
2.80
12 Months
1.76
1.20
1.64
1.85
1.42
1.77
1.65
1.41
1.96
1975
12 Months
1.80
1.26
1.55
1.84
1.42
1.81
1.70
1.47
2.04
15 Months
1.50
1.05
1.35
1.58
1.23
1.57
1.44
1.22
1.83
21 Months
1.10
0.76
0.94
1.19
0.93
1.16
1.11
0.95
1.32
93
-------
Table 9. Differential Corrosion Rates (ym/yr) for Weathering
Steel Calculated According to Eq. (5)
First Set
Site #
103
105
106
108
112
115
118
120
122
3 Mo.
"2774
21.1
20.5
28.0
22.5
28.4
25.2
20.0
30.4
6 Mo.
18.4
14.7
14.4
19.4
16.1
21.0
19.0
13.4
21.8
12 Mo.
TO
10.3
10.1
13.4
11.5
15.5
14.3
8.9
15,6
18 Mo.
9.7
8.3
8.2
10.8
9.5
12.9
12.1
7.1
12.9
24 Mo.
8.2
7.2
7.1
9.3
8.3
11.4
10.8
.6.0
il.2
30 Mo
7.2
6.4
6.3
8.3
7.4
10.3
9.8
5.3
10.1
Second Set
Site #
103
105
106
108
112
115
118
120
122
3 Mo.
27.2
22.7
27.0
27.4
22.7
32.4
30.7
21.3
30.4
6 Mo.
18.9
16.2
21.2
21.1
16.9
25.4
25.1
15.0
21.5
12 Mo.
13.1
li.5
16.6
16.2
11.1
19.9
20.5
10.5
15.2
18 Mo.
10.5
9.4
14.4
13.9
9.0
17.3
18.3
8.6
12.4
24 Mo.
9.0
8.2
13.0
12.4
7.7
15.6
16.8
7.4
10.7
30 Mo.
8.0
7.3
12.1
11.4
6.9
14.5
15.7
6.6
9.6
94
-------
Table 9 (Continued)
Third Set
Site #
103
105
106
108
112
115
118
120
122
Site #
103
105
106
108
112
115
118
120
122
3 Mo.
26.9
18.0
24.8
26.2
16.4
24.2
25.3
20.0
28.4
3 Mo.
22.9
13.0
20.4
22.9
18.6
23.6
22.0
17.2
16.4
6 Mo.
18.9
12.3
18.1
17.4
9.9
15.5
18.6
13.4
19.0
6 Mo.
14.4
7.7
13.0
14.4
11.8
25.2
14.1
10.6
16.9
12 Mo.
13.3
8.4
13.1
11.5
6.0
10.0
13.7
8.9
12.7
Fourth Set
12 Mo.
9.0
4.5
8.3
9.0
7.4
9.7
9.1
6.5
10.9
18 Mo.
10.8
6.7
10.9
9.1
4.4
7.7
11.5
7.1
10.1
18 Mo.
6.9
3.3
6.4
6.9
5.7
7.5
7.0
4.9
8.4
24 Mo.
9.3
5.7
9.5
7.7
3.6
6.4
10.1
6.0
8.5
14 Mo.
5.7
2.7
5.3
5.7
4.7
6.2
5.8
4.0
7.0
30 Mo
8.3
5.1
8.6
6.7
3.1
5.5
9.2
5.3
7.5
30 Mo
*r\s 1 l\s
4.9
2.3
4.6
4.9
4.1
5.4
5.0
3.4
6.0
95
-------
Table 10. Weight Loss of House Paint on Stainless Steel (mg)
(Average of 3 Samples)
I. Latex Base Exposure to North
Site #
103
105
106
108
112
115
118
120
122
Site #
103
105
106
108
112
115
118
120
122
3 Mo.
19.7 + 4.1
14.8 + 5.1
18.8 + 5.3
16.0 + 1.2
25.9 + 1.3
21.9 + 3.7
20.1 + 2.8
22.0 + 1.9
26.5 + 5.5
3 Mo.
23.1 + 4.1
13.7 + 1.2
16.4 + 1.7
24.2 + 4.4
18.6 + 1.3
17.2 + 1.2
18.3 + 3.3
18.9 + 0.1
27.2 + 4.9
6 Mo.
22.6 + b.4
19.7 + 4.5
20.6 + 2.4
30.4 + 7.1
22.8 + 3.0
30.1 + 2.3
27.9 + 2.1
24.4 + 4.7
28.1 + 1.4
II. Latex
6 Mo.
30.3 + 6.6
19.8 + 2.0
24.1 + 1.0
27.6 + 6.8
21.5 + 2.5
33.3 + 3.0
26.5 + 4.0
25.6 + 2.5
30.2 + 1.9
12 Mo.
60.3 + 7.2
50.9 + 2.7
55.1 + 1.0
67.5 + 2.2
53.5 + 5.1
69.5 + 0.3
81.3 + 12.4
67.2 + 3.0
73.3 + 3.6
Base Exposure to
12 Mo.
77.2 + 4.4
66.3 + 3.1
68.7 + 3.1
88.6 + 4.6
74.1 + 0.2
82.4 + 1.4
81.5 + 1.9
78.9 + 2.9
97.7 + 4.9
24 Mo.
86.1 + 3.0
102.2 + 2.8
95.7 + 4.2
123.2 + 2.8
96.0 + 2.7
132.6 + 4.5
140.8 + 3.1
120.7 + 1.4
147.1 + 8.2
South
24 Mo.
139.2 + 8.8
131.7 + 2.8
137.5 + 3.0
160.8 _+ 9.1
125.4 + 1.7
166.5 + 3.4
160.5 + 2.7
152.4 + 2.6
195.0 + 6.6
30 Mo.
112.7 + 1.5
116.6 + 3.3
121.8 + 5.1
139.4 + 2.6
116.8 + 7.0
169.2 + 0.3
179.2 + 7.3
156.1 + 6.1
178.1 + 1.5
30 Mo.
160.1 + 6.5
154.8 + 3.3
82.9 + 0.5
160.8 + 9.1
155.5 + 3.0
204.6 + 3.1
197.1 + 1.1
171.4 + 5.2
231.4 + 1.0
96
-------
Table 10. (Continued)
III. Oil Base, Exposure to North
Site #
103
105
106
108
112
115
118
120
122
Site #
103
105
106
108
112
115
118
120
122
3 Mo.
19.1 + 1.1
18.2 + 0.9
15.6 + 1.6
16.0 + 0.7
15.9 + 0.5
18.2 + 0.7
18.4 + 0.5
18.1 + 1.0
19.5 + 0.6
3 Mo.
19.5 + 1.1
21.1 + 1.6
15.6 + 0.3
17.3 + 0.6
17.6 + 1.2
19.0 + 0.6
18.5 + 0.4
19.1 + 1.4
19.8 + 0.3
6 Mo.
25.5 + 1.2
19.7 + 0.4
16.7 + 1.4
19.3 + 0.7
19.6 + 0.4
21,2 + 2.4
23.5 + 5.0
19.0 + 0.9
20.9 + 0.4
IV Oil Base,
6 Mo.
23.7 + 0.8
22.3 + 0.5
18.3 + 0.3
21.0 + 1.5
22.0 + 1.8
21.1 + 0.6
21.0 + 0.6
22.0 + 1.7
22.4 + 1.0
12 Mo.
63.9 + 2.6
57.9 + 4.0
49.6 + 5.2
60.7 + 0.4
51.8 + 0.6
62.1 + 2.8
67.0 + 0.5
64.7 + 2.3
67.5 + 2.8
Exposure to
12 Mo.
70.4 + 2.2
66.9 + 3.0
57.7 + 1.5
66.8 + 2.7
58.5 + 0.9
64.0 + 1.5
70.4 + 2.0
67.4 + 0.4
68.8 + 5.0
24 Mo.
79.7 + 2.4
79.9 + 5.7
64.9 + 1.4
82.3 + 1.9
72.7 + 2.7
79.9 + 5.9
78.7 + 5.1
78.7 + 2.1
89.4 + 2.8
South
24 Mo.
96.5 + 3.4
96.6 + 3.9
76.7 + 0.0
94.2 + 0.9
80.9 + 1.0
92.0 + 1.9
92.7 + 3.0
88.4 + 4.4
93.9 + 1.0
30 Mo.
93.1 + 5.2
95.8 + 4.4
82.9 + 0.5
90.5 + 6.0
76.4 + 3.5
83.4 + 6.4
92.0 + 2.5
87.1 + 0.8
104.1 + 3.6
30 Mo.
105.3 + 8.5
113.5 + 3.4
90.0 + 3.5
106.3 + 2.2
97.4 + 3.4
99.7 + 3.1
101.3 + 1.1
105.8 + 3.3
105.7 + 3.3
97
-------
Table 11
Integral Corrosion Rates V-j (ug/cm2 month) for
House Paint (Area = 155 cm^)
I. Latex Facing North
Site
103
105
106
108
112
115
118
120
122
Site #
103
105
106
108
112
115
118
120
122
3 Months
42.6
31.8
40.4
34.4
55.7
47.1
43.2
47.3
57.0
3 Months
49.6
29.5
35.3
52.0
40.0
37.0
39.4
40.6
58.5
6 Months
24.3
21.2
22.2
32.7
24.5
32.4
30.0
26.2
30.2
II. Latex
6 Months
32.6
21.3
25.9
29.7
23.1
35.8
28.5
27.5
32.5
12 Months
32.4
27.4
29.6
36.3
28.8
37.4
43.7
36.1
39.4
Base Facing South
12 Months
41.5
35.6
36.9
47.6
34.8
44.3
43.8
42.4
52.5
12 Months
23.1
27.5
25.7
33.1
25.8
35.6
37.8
32.4
39.5
24 Months
37.4
35.4
37.0
43.6
33.7
44.8
43.1
41.0
52.4
30 Months
24.2
25.1
26.2
30.0
25.1
36.4
38.5
33.6
38.3
30 Months
34.4
33.3
34.1
39.7
33.4
44.0
42.4
36.9
49.8
98
-------
Table 11 (Continued)
III. Oil Base Facing North
Site #
103
105
106
108
112
115
118
120
122
Site #
103
105
106
108
112
115
118
120
122
3 Months
41.1
39.1
33.5
34.4
34.2
39.1
39.6
38.9
41.9
3 Months
41.9
45.4
33.5
37.2
37.8
40.9
39.8
41.1
42.6
6 Months
27.4
21.1
18.0
20.7
20.7
22.8
25.3
20.4
22.5
IV. Oil
6 Months
25.5
24.0
19.7
22.6
23.7
22.7
22.6
23.7
24.1
12 Months
34.4
31.1
26.7
32.6
27.8
33.4
36.0
34.8
36.3
Base Facing South
12 Months
37.8
36.0
31.0
35.9
31.5
34.4
37.8
35.2
37.0
24 Months
21.4
21.5
17.4
22.1
19.5
21.5
21.2
21.2
24.0
24 Months
25.9
26.0
20.6
25.3
21.7
24.7
24.9
23.8
25.2
30 Months
20.0
20.6
17.8
19.5
16.4
17.9
19.8
18.7
22.4
30 Months
22.6
24.4
19.4
22.9
20.9
21.4
21.8
22.8
22.7
99
-------
Table 12. Weight Loss Data for Marble (mg)
(Average of 3 Samples)
Site # 3 Mo. 6 Mo. 12 Mo. 24 Mo. 30 Mo.
103 303 480 1282 1549 1787
105 366 584 1074 1746 1912
106 328 554 989 1472 1689
108 379 636 1235 1675 2109
112 349 565 1128 1601 1786
115 397 685 1093 1655 1949
118 373 664 1074 1710 1974
120 394 647 1055 1551 1806
122 486 679 1273 1791 2091
3 Mo.
303
366
328
379
349
397
373
394
486
Table 13.
3 Mo.
276
333
299
345
318
362
340
359
443
6 Mo.
480
584
554
636
565
685
664
647
679
12 Mo.
1282
1074
989
1235
1128
1093
1074
1055
1273
Corrosion Rates V-j (yg/cm
Marble (Total Area = 366
6 Mo.
219
266
252
290
257
312
302
295
309
12 Mo.
292
245
225
281
257
249
245
240
290
24 Mo.
1549
1746
1472
1675
1601
1655
1710
1551
1791
2 month) for
cm2)
24 Mo.
176
199
168
191
182
188
195
177
204
Site # 3 Mo. 6 Mo. 12 Mo. 24 Mo. 30 Mo.
103 276 219 292 176 163
105 333 266 245 199 174
106 299 252 225 168 154
108 345 290 281 191 192
112 318 257 257 182 163
115 362 312 249 188 178
118 340 302 245 195 180
120 359 295 240 177 164
190
100
-------
Table 14a. Average Reflectance Loss (%) for Ag, First Year
(Average of 4 Measurements per Sample,
Duplicate Samples)
Site #
103
105
106
108
112
115
118
120
122
Site #
3
38
27
16
66
21
74
21
23
63
Table
Months
.3 + 2.3
.6 + 5.0
.7 + 0.8
.0 + 0.8
.6 + 0.7
.1 + 3.8
.4 + 0.3
.3 + 0.7
.4 + 0.3
6 Months
57.9 + 8.9
55.8 + 1.2
31.9 + 5.2
74.7 + 1.6
36.4 + 0.4
66.2 + 1.4
36.5 + 6.8
42.8 + 1.4
58.4 + 0.8
14b. Reflectance Loss and Film
(Values Correspond to one
Table 14a)
3 Months
6 Months
9 Months
70.7 + 4.7
70.2 + 4.7
52.5 + 9.8
65.0 + 0.8
51.4 + 1.7
83.5 + 0.7
61.2 _+ 0.4
56.9 + 0.1
67.0 + 2.7
Thickness for Ag
of the Duplicate
9 Months
12 Months
67.7 + 4.5
78.4 + 4.5
62.0 + 10.3
73.7 + 1.8
56.6 + 6.0
81.5 + 3.7
51.9 + 2.3
60.5 + 6.6
66.2 + 0.5
, First Year
Samples in
12 Months
103
105
106
108
112
115
118
120
122
RL(%)
41
33
17
67
21
78
21
23
63
d(A)
202
163
133
386
127
382
122
149
296
RL(%) d(A)
67 312
54 252
37 151
73 445
36 150
64 266
41 171
44 189
69 359
RL(%) d(ft)
75 409
66 322
43 155
66 379
53 188
84 395
62 209
57 231
70 306
RL(%) d(K)
72 334
77 340
72 324
72 407
63 212
78 311
54 186
67 232
67 215
-------
Table 15a. Average Reflectance Loss (%} for Ag, Second Year
(Average of 4 Measurements per Sample, Duplicate Samples)
Site #
3 Months
6 Months
9 Months
12 Months
103
105
106
108
112
115
118
120
122
36
26
23
75
25
52
33
30
57
.4 +
.5 +
.3 +
.1 +
.9 +
.8 +
.4 +
.1 +
.2 +
0.3
1.9
4.2
4.5
0.0
4.3
0.4
0.0
10.6
48.
44.
40.
79.
72.
55.
58.
75.
9 + 0
5 + 5
7 + 4
9 + 4
n.d.
2 + 9
0 + 2
5 + 1
7 + 7
.6
.2
.5
.0
.2
.0
.9
.1
65.
54.
53.
87.
55.
87.
62.
70.
82.
1 +
5 +
8 +
2 +
3 +
6 +
6 +
9 +
3 +
5.2
0.2
0.0
5.1
6.8
1.0
5.8
3.6
0.6
76.6
77.0
68.8
93.6
66.4
87.0
77.6
80.0
86.4
± 2-7
+ 0.2
+ 0.4
+ 0.2
+ 4.6
+ 4.0
+ 3.4
+ 1.4
+ 3.5
n.d. = not determined
Table 15b. Reflectance Loss and Film Thickness for Ag, Second Year
(Values Correspond to one of the Duplicate Samples in
Table 15a)
Site #
103
105
106
108
112
115
118
120
122
3 Months
RL(*)
36.1
28.4
27.4
79.6
25.9
48.5
33.8
30.1
46.6
d(A)
166
154
145
370
130
167
181
151
154
6 Months
RL(%)
54.4
49.6
45.2
75.9
n.d.
63.0
57.0
56.6
68.6
d(A)
220
173
161
n.d.
164
240
211
195
248
9 Months
RL(%)
70.2
54.3
53.8
92.3
48.5
86.6
56.8
67.3
81.7
d(A)
325
247
161
730
182
370
223
257
389
12 Months
RL(%)
79.3
77.2
68.4
93.8
71.0
91.0
74.2
81.5
82.9
d(A;
471
423
298
883
289
500
325
376
494
-------
Table 16. Time-To-Failure of Al Tension Samples (Days)
I. 50% of All Samples
Site #
103
105
106
108
112
115
118
120
122
Al 7079
25 Ksi
125
150
160
165
210
225
160
155
160
Al 7079
15 Ksi
224
245
370
250
270
270
260
320
133
Al 2014
45 Ksi
<48
60
230
<48
410
100
105
75
75
Al 2014
25 Ksi
575
450
822
755
822
II. 100% of AH Samples
103
105
106
108
112
115
118
120
122
172
160
210
210
240
255
220
224
201
382
360
622
381
622
346
630
U)
277
66
230
505
225
(1)
(1)
155
83
814
(2)*
822
(8)
871
(6)
(7)
(1)
(3)
(4)
* Number of samples left.
103
-------
Table 17. Results of Nylon Exposure
Site # Sample w/Holes No. of Holes Remarks
120
108
118
103
106
108
112
115
118
120
122
103
105
106
108
112
120
122
1
1
2
2
1
2
2
1
2
2
2
1
1
1
2
2
2
1
1st Set, Start October 1965
6
2nd Set, Start January 1976
1
8
3rd Set, Start April 1976
1 Severe
3
3 Severe
4 Severe
1
4
Severe
10
4th Set, Start July 1976
6
1
7
1 Severe
10
17
2
damage on other sample
damage on other sample
damage on other sample
damage on both samples
damage on other sample
104
-------
Table 18. Quarterly Averages of Air Quality Data for the Period
Between Nov. 10, 1974 and March 31, 1977
Key:
WS = wind speed (m/sec)
WD = wind direction (degrees)
T = temperature (°C)
Ozone (ppb)
THC = total hydrocarbon (ppm)
NOX (ppb)
TS = total sulfur (ppb)
H2S, S02 (ppb)
RH = relative humidity (%)
105
-------
Table 18 (Continued)
I. Average for the Period Nov. 10, 1974 through Jan. 14, 1975
Site #
103
105
106
108
112
115
118
120
122
Site #
103
105
106
108
112
115
118
120
122
MS
4.04
3.81
3.90
3.93
4.37
3.75
3.50
4.44
4.92
II.
WS
4.63
4.10
4.64
4.19
4.31
4.12
3.70
4.20
5.16
WD
217
212
211
205
215
202
209
213
203
Averages
WD
192
195
188
187
187
190
187
190
134
T
2.92
3.33
3.46
2.62
3.34
2.64
2.74
2.73
1.61
for
T
3.01
3.48
3.43
2.67
3.52
2.75
3.02
3.02
1.97
Ozone
7.
7.
6.
9.
7.
12.
17.
9.
15.
1
8
6
5
6
5
0
2
7
Period Jan
Ozone
19.
16.
16.
21.
17.
24.
26.
21.
32.
2
3
0
6
7
5
8
5
8
THC
1.56
2.29
1.84
1.93
1.76
1.41
1.38
1.72
1.74
. 15,
THC
1.66
2.37
1.82
1.84
1.64
1.41
1.29
1.69
1.71
NOX
41.3
49.8
40.3
36.5
44.0
20.4
14.7
35.4
10.7
1975
NOX
20.8
54.4
50.7
31.7
43.5
15.5
19.4
32.3
8.4
TS
31.8
22.6
32.9
52.8
11.5
50.7
7.0
8.3
63.3
through
TS
13.8
21.7
49.8
38.0
12.9
47.4
9.2
9.4
46.1
M2l
2.5
7.4
2.5
2.5
n.d.
2.5
n.d.
2.6
2.5
Apr. 14
H2$
3.2
12.8
-
13.8
n.d.
-
n.d.
2.8
_
S0_2
32.6
14.5
31.7
44.9
n.d.
46.6
n.d.
8.7
42.7
, 1975
S0_2
11.4
15.7
46.5
35.6
n.d.
44.1
n.d.
8.8
34.0
RH
70.9
69.7
71.1
72.4
83.6
81.0
68.6
73.5
75.6
RH
75.4
69.2
73.9
70.8
67.7
78.2
73.6
68.7
67.6
n.d. - not determined.
106
-------
Table 18 (Continued)
III. Averages for Period Apr. 15. 1975 through July 8, 1975
Site #
103
105
106
108
112
115
118
120
122
Site #
103
105
106
108
112
115
118
120
122
MS
4.22
2.99
3.48
3.32
3.21
3.06
3.19
4.47
4.48
IV.
WS
3.80
3.04
3.16
2.37
2.63
2.30
3.55
2.86
3.57
WD
184
171
184
191
196
170
167
158
237
Averages
WD
189
191
194
181
196
167
163
177
190
T
21.2
22.2
21.9
21.0
21.8
20.8
21.1
19.9
19.2
for
T
21.6
22.5
22.1
20.1
20.7
21.1
20.9
19.8
19.4
Ozone
34.1
32.4
36.0
34.9
32.7
35.1
55.3
39.2
47.3
Period
Ozone
20.1
25.1
27.9
24.8
26.4
34.9
40.8
33.9
37.5
THC
1.95
2.17
1.86
1.87
1.54
1.41
1.32
1.84
1.64
July 9,
THC
2.20
2.25
2.20
1.98
1.89
170
1.51
2.04
1.63
NOX
30.1
38.3
32.0
24.9
35.4
12.5
10.3
31.2
6.1
TS
10.
13.
23.
6.
9.
34.
5.
11.
21.
1975 through
NOX
32.9
43.1
48.6
34.5
62.5
19.1
14.1
27.2
9.0
TS
11.
12.
8.
8.
16.
50.
7.
5.
6.
8
7
6
5
2
1
6
4
6
Oct
1
0
7
8
2
3
6
8
9
H2i
3.3
14.2
5.5
6.6
n.d.
2.9
n.d.
2.8
5.1
. 14,
H2$
11.2
9.6
4.3
2.6
n.d.
120
n.d.
9.2
3.6
SO?
8.5
10.6
23.6
6.3
n.d.
21.4
n.d.
5.4
12.7
1975
SO?
9.5
9.8
11.6
8.5
n.d.
28.8
n.d.
5.2
6.0
RH
40.0
57.4
69.0
63.8
60.4
72.7
61.6
65.0
69.2
RH
52.6
66.8
66.4
60.7
60.4
70.0
58.3
68.6
60.5
107
-------
Table 18 (Continued)
V. Averages for Period Oct. 15, 1975 through Jan. 14, 1976
Site #
103
105
106
108
112
115
118
120
122
Site #
103
105
106
108
112
115
118
120
122
WS
5.30
4.32
3.93
4.67
3.92
3.91
4.07
4.62
5.63
VI.
WS
5.80
5.00
4.63
4.88
4.59
4.27
4.34
5.22
5.97
WD
201
200
202
187
202
187
189
198
199
Averages
WD
200
196
203
193
198
184
189
195
201
T
5.62
6.39
5.95
5.49
6.38
5.50
6.08
5.36
5.02
Ozone
12.0
10.9
13.4
19.9
12.2
19.8
23.1
14.3
21.3
for Period
T
7.30
8.19
8.30
7.33
8.18
6.97
7.77
7.07
6.29
Ozone
22.3
18.7
19.4
22.0
20.8
26.0
29.5
21.1
34.7
THC
1
2
2
2
1
1
1
1
1
Jan.
2
2
2
2
1
1
1
1
1
.92
.29
.27
.19
.82
.62
.73
.80
.74
15,
THC
.05
.12
.19
.02
.84
.60
.57
.77
.86
NOX
44.3
49.5
84.4
38.8
58.4
22.6
16.0
35.2
15.7
TS
16.1
14.1
16.4
15.6
19.6
67.0
8.0
9.0
14.6
1976 through
NOX
44.8
52.3
47.9
39.2
49.8
16.4
13.7
32.6
11.2
TS
14.3
15.7
18.0
13.6
14.7
14.4
7.4
11.8
13.3
Hzi
5.9
7.7
11.0
4.9
n.d.
126
n.d.
12.8
3.4
Apr. 14
H2S
3.6
7.2
6.0
3.6
n.d.
22.7
n.d.
9.3
7.6
S0_2
13.0
11.2
13.5
14.0
n.d.
44.6
n.d.
7.7
12.2
, 1976
SOj?
12.1
12.8
13.6
11.5
n.d.
8.8
n.d.
8.8
10.6
RH
61.1
61.7
67.2
59.2
58.1
72.7
69.5
64.7
69.6
RH
55.2
64.9
66.2
70.1
64.5
69.4
68.2
59.3
69.8
108
-------
Table 18 (Continued)
VII. Averages for Period Apr. 15, 1976 through July 14, 1976
Site #
103
105
106
108
112
115
118
120
122
Site #
103
105
106
108
112
115
118
120
122
WS
4.51
3.94
3.46
3.66
3.47
3.17
3.32
4.02
4.38
VIII.
WS
3.86
3.33
2.96
3.03
3.00
2.60
2.78
3.14
2.46
WD
181
177
183
179
186
164
165
183
184
Averages
WD
174
166
172
168
177
152
158
171
174
T
20.1
20.9
20.8
19.9
20.1
19.6
19.4
19.6
18.6
for
T
21.8
22.8
22.5
21.2
22.1
21.1
21.5
21.3
20.0
Ozone
35.5
35.8
33.2
37.5
34.1
42.3
48.4
38.5
47.6
Period
Ozone
35.1
34.9
34.8
36.8
32.6
49.0
51.6
39.4
45.2
THC
1.
2.
2.
1.
1.
1.
1.
1.
1.
July
95
16
09
95
92
61
65
92
73
15,
THC
2.
2.
2.
2.
2.
1.
1.
2.
i.
20
42
29
16
21
82
75
12
76
NOX
37.8
43.1
42.6
31.7
41.8
14.7
13.3
30.0
7.4
1976
NOX
59.2
50.2
50.8
43.1
52.0
18.1
16.1
34.9
14.3
TS
11.0
19.0
14.8
10.0
7.7
9.3
7.7
8.8
17.4
through
TS
8.8
19.4
16.4
26.0
8.8
15.1
8.3
14.4
19.8
U2S
6.2
8.7
3.5
3.0
n.d.
14.1
n.d.
7.9
13.6
Oct.
iizi
2.6
2.6
2.5
5.1
n.d.
8.3
n.d.
8.8
2.6
SO?
9.0
17.1
14.6
9.1
n.d.
5.9
n.d.
7.5
8.7
14, 1976
S0_2
7.5
14.7
14.6
13.6
n.d.
7.3
n.d.
8.2
7.8
RH
52.5
69.6
63.2
63.6
73.2
68.3
71.8
73.9
61.3
RH
52.0
65.5
62.1
72.3
70.1
62.0
68.2
66.1
66.7
109
-------
Table 18 (Continued)
IX. Averages for Period Oct. 15, 1976 through Jan. 14, 1977
Site #
103
105
106
108
112
115
118
120
122
Site #
103
105
106
108
112
115
118
120
122
WS
4.
3.
3.
3.
3.
3.
3.
4.
3.
X.
83
96
83
95
53
55
23
31
39
WD
232
222
226
226
231
211
212
233
231
Averages
WS
4.
4.
4.
4.
4.
4.
4.
5.
5.
85
63
63
87
28
41
23
31
75
MO
229
222
219
219
228
205
210
204
237
T
1.42
2.43
1.83
1.05
2.00
0.76
1.40
0.96
-0.32
Ozone
20.0
8.7
8.0
14.1
11.0
15.1
17.7
11.9
19.2
for Period Jan
T
2.67
4.42
6.14
3.06
4.14
4.13
3.34
3.30
2.04
Ozone
20.0
17.9
20.9
23.7
20.9
29.1
32.3
23.3
31.9
THC
1.99
2.41
2.36
2.04
2.26
1.92
1.94
2.16
1.75
. 15,
THC
1.86
2.28
2.10
1.97
2.10
1.78
1.77
1.84
1.68
NOX
54.3
66.2
71.8
47.1
60.9
27.3
25.1
49.4
13.0
TS
11.9
22.2
23.3
25.4
12.2
21.7
12.2
18.0
20.3
1977 through
NOX
40.4
50.0
42.9
35.3
44.2
19.8
14.3
32.9
9.0
TS
9.5
18.5
15.0
20.5
11.9
14.3
9.6
15.4
13.6
H2l
2.8
3.3
2.5
4.2
n.d.
8.4
n.d.
9.9
2.6
Mar. 31,
H2S
2.5
3.0
2.6
2.8
n.d.
4.9
n.d.
9.7
2.5
S0_2
11.2
15.7
20.7
16.0
n.d.
13.6
n.d.
10.1
11.4
1977
SO?
8.7
12.3
12.7
13.5
n.d.
10.3
n.d.
8.4
8.5
RH
66.6
71.1
66.8
78.5
57.1
40.1
70.1
70.8
68.1
RH
48.9
90.1
63.5
72.9
57.1
47.6
72.9
73.5
57.0
110
-------
Table 19. Quarterly Averages of Total Suspended Particulates,
Sulfates and Nitrates (
I. Jan. 15, 1975 through April 14, 1975
Site #
103
105
106
108
112
115
118
120
122
TSP
90.7 (3)
80.5 (10)
87.6 (7)
59.4 (11)
70.2 (10)
44.3 (6)
55.5 (6)
63.6 (6)
34.8 (11)
S04
17.8 (3)
10.4 (10)
12.8 (7)
10.5 (11)
9.8 (10)
10.4 (6)
5.9 (6)
10.9 (6)
7.6 (11)
NOj
8.6 (3)
5.6 (10)
6.4 (7)
5.7 (11)
5.4 (10)
4.1 (6)
2.8 (6)
5.7 (6)
4.9 (11)
II. April 15, 1975 through July 8, 1975
Site #
103
105
106
108
112
115
118
120
122
TSP
107.8 (17)
97.4 (18)
91.5 (17)
92.2 (23)
98.4 (21)
72.6 (17)
93.4 (23)
95.2 (12)
68.3 (24)
S04
12.5 (17)
13.8 (18)
14.5 (17)
15.2 (23)
14.9 (21)
15.9 (17)
12.4 (23)
17.5 (12)
15.7 (24)
NOj
2.5 (17)
4.2 (18)
3.2 (17)
3.3 (23)
3.0 (21)
2.5 (17)
2.5 (22)
4.8 (12)
2.8 (24)
Values in Brackets Indicate Number of Sample Days
111
-------
Table 19 (Continued)
III. July 9, 1975 through Oct. 14. 1975
Site #
103
105
106
108
112
115
118
120
122
TSP
100.5 (30)
86.3 (26)
76.1 (20)
94.1 (28)
96.8 (28)
62.9 (26)
61.5 (26)
74.6 (18)
54.0 (27)
S04
14.5 (30)
14.4 (26)
17.1 (20)
17.4 (28)
15.5 (28)
14.1 (26)
11.6 (26)
17.3 (18)
13.3 (27)
NOs
3.1 (30)
3.3 (26)
2.8 (20)
3.9 (20)
3.2 (28)
2.7 (26)
2.2 (26)
3.7 (18)
2.2 (27)
IV. Oct. 15, 1975 through Jan. 14, 1976
Site #
103
105
106
108
112
115
118
120
122
TSP
83.8 (28)
73.3 (30)
60.5 (28)
67.0 (28)
54.5 (30)
41.8 (27)
45.8 (27)
46.6 (23)
38.3 (30)
S04
11.1 (28)
10.3 (30)
10.3 (28)
11.6 (28)
10.1 (30)
9.4 (27)
9.9 (27)
8.9 (23)
8.8 (30)
N0_3
4.2 (28)
4.2 (30)
4.0 (28)
4.1 (28)
3.3 (30)
3.8 (27)
3.5 (27)
3.7 (23)
3.8 (30)
112
-------
Table 19 (Continued)
V. Jan. 15. 1976 through April 14, 1976
Site #
103
105
106
108
112
115
118
120
122
TSP
94.5 (27)
90.2 (17)
78.5 (28)
80.8 (27)
73.6 (28)
46.5 (23)
59.1 (27)
48.7 (28)
46.7 (26)
SO-4
10.2 (27)
9.8 (17)
10.6 (28)
10.8 (27)
8.9 (28)
8.9 (23)
9.2 (28)
8.1 (28)
9.3 (26)
NOj
4.0 (27)
4.5 (27)
4.2 (27)
4.1 (27)
4.1 (28)
4.3 (23)
3.8 (27)
3.8 (28)
4.5 (26)
VI. April 15. 1976 through July 14, 1976
Site f TSP S04
103 94.5 (26) 14.1 (16) 3.6 (26)
105 86.6 (29) 14.3 (29) 3.6 (29)
106 80.0 (30) 13.0 (30) 3.4 (30)
108 99.3 (29) 14.9 (29) 3.4 (29)
112 80.0 (29) 13.0 (29) 3.2 (29)
115 64.1 (28) 11.7 (29) 2.9 (29)
118 78.9 (29) 11.8 (29) 2.2 (29)
120 53.4 (29) 11.8 (28) 2.7 (28)
122 64.6 (30) 11.6 (31) 3.0 (31)
113
-------
Table 19 (Continued)
VII. July 15, 1976 through Oct. 14, 1976
Site # TSP S04 Npj
103 126.3 (29) 19.6 (29) 4.3 (29)
105 102.9 (30) 17.5 (30) 4.1 (30)
106 90.3 (29) 16.2 (29) 3.3 (29)
108 120.5 (29) 20.2 (29) 4.0 (29)
112 107.1 (29) 17.4 (29) 3.1 (29)
115 72.0 (30) 14.7 (30) 3.1 (29)
118 77.4 (29) 16.9 (29) 3.0 (28)
120 62.6 (26) 14.8 (26) 3.0 (26)
122 69.4 (29) 16.4 (29) 3.2 (28)
TSP S04
126.3 (29)
102.9 (30)
90.3 (29)
120.5 (29)
107.1 (29)
72.0 (30)
77.4 (29)
62.6 (26)
69.4 (29)
VIII. Oct.
TSP
79.7 (31)
82.5 (31)
71.9 (31)
64.7 (31)
59.0 (31)
55.6 (31)
54.3 (30)
55.6 (31)
55.8 (31)
19.6 (29)
17.5 (30)
16.2 (29)
20.2 (29)
17.4 (29)
14.7 (30)
16.9 (29)
14.8 (26)
16.4 (29)
15, 1976 through Jan. 14, 1977
S04
9.7 (31)
9.4 (31)
8.3 (31)
9.1 (31)
7.7 (31)
8.5 (31)
8.7 (31)
7.3 (31)
8.4 (31)
Site f TSP S04 N03
103 79.7 (31) 9.7 (31) 4.0 (31)
105 82.5 (31) 9.4 (31) 4.0 (31)
106 71.9 (31) 8.3 (31) 3.5 (31)
108 64.7 (31) 9.1 (31) 3.6 (31)
112 59.0 (31) 7.7 (31) 3.5 (31)
115 55.6 (31) 8.5 (31) 3.5 (31)
118 54.3 (30) 8.7 (31) 3.5 (31)
120 55.6 (31) 7.3 (31) 3.6 (31)
122 55.8 (31) 8.4 (31) 4.2 (31)
114
-------
Table 19 (Continued)
IX. Jan. 15, 1977 through Mar. 31, 1977
Site t TSP SOa
103 74.2 (24) 9.7 (25) 3.6 (25)
105 84.1 (25) 8.7 (25) 4.3 (25)
106 72.8 (25) 7.9 (25) 3.5 (25)
108 75.7 (25) 10.1 (25) 4.3 (25)
112 58.6 (25) 7.4 (25) 3.6 (35)
115 46.0 (25) 8.0 (25) 4.1 (25)
118 44.6 (24) 8.0 (24) 3.6 (24)
120 49.0 (25) 6.9 (25) 3.7 (25)
122 40.1 (25) 7.7 (25) 4.1 (25)
115
-------
Table 20. Average Concentration for Different Exposure
Periods and Start of Exposure
I. Total Sulfur (ppb)
Start Nov. 10. 1974
Site #
3 Mo.
6 Mo.
12 Mo
24 Mo.
30 Mo,
103
105
106
108
112
115
118
120
122
31.8
22.6
32.9
52.8
11.5
50.7
7.0
8.3
63.3
22.8
22.2
41.3
45.4
12.2
49.1
8.1
8.9
54.7
16.9
17.6
28.9
26.5
12.5
45.6
7.4
8.7
34.5
14.7
17.3
22.6
21.4
14.4
36.0
7.6
9.9
25.4
13.9
17.9
21.9
21.7
13.9
32.4
8.3
11.3
23.7
Start Jan. 15. 1975
Site #
3 Mo.
6 Mo.
12 Mo.
24 Mo.
103
105
106
108
112
115
118
120
122
13.8
21.7
49.8
38.0
12.9
47.4
9.2
9.4
46.1
12.3
17.7
36.7
22.3
11.1
40.8
7.4
10.4
33.9
12.0
15.4
24.6
17.2
14.5
49.7
7.6
8.9
22.3
12.2
17.2
21.4
18.0
13.2
32.4
8.3
11.1
20.0
116
-------
Table 20 (Continued)
Start Apr. 15, 1975
Site #
103
105
106
108
112
115
118
120
122
3 Mo.
10.8
13.7
23.6
6.5
9.2
34.1
5.6
11.4
21.6
6 Mo.
11.0
12.9
16.2
7.7
12.7
42.2
6.6
8.6
14.3
12 Mo
13.1
14.4
16.7
11.1
14.9
41.5
7.2
9.5
14.1
15 Mo.
12.7
15.3
16.3
10.9
13.5
35.0
7.3
9.4
14.8
24 Mo
11.7
17.1
17.0
14.6
13.0
28.3
8.3
11.8
15.9
Start July 9, 1975
Site #
103
105
106
108
112
115
118
120
122
3 Mo.
11.1
12.0
8.7
8.8
16.2
50.3
7.6
5.8
6.9
6 Mo.
13.6
13.1
12.6
12.2
17.9
58.7
7.8
7.4
10.8
12 Mo.
13.1
15.2
14.5
12.0
14.6
35.3
7.7
8.9
13.1
21 Mo.
11.8
17.3
16.1
15.7
13.6
27.4
8.7
11.9
15.1
117
-------
n.d. - not determined.
Table 20 (Continued)
II. SO? (ppb)
Start Nov. 10, 1974
Site #
103
105
106
108
112
115
118
120
122
3 Mo.
32.6
14.5
31.7
44.9
n.d.
46.6
n.d.
8.7
42.7
6 Mo.
22.0
15.1
39.1
40.3
n.d.
45.4
n.d.
3.8
38.4
12 Mo
15.5
12.7
28.4
23.8
n.d.
35.2
n.d.
7.0
23.9
24 Mo.
13.0
13.3
2i.2
17.9
n.d.
25.9
n.d.
7.5
16.8
30 Mo
12.4
13.4
20.3
17.3
n.d.
23.1
n.d.
7.9
15.5
Start Jan. 15, 1975
Site #
103
105
106
108
112
115
118
120
122
3 Mo.
11.4
15.7
46.5
35.6
n.d.
44.1
n.d.
8.8
34.0
6 Mo.
10.0
13.2
35.1
21.0
n.d.
32.8
n.d.
7.1
23.4
12 Mo.
10.6
11.8
23.8
16.1
n.d.
34.7
n.d.
6.8
16.2
24 Mo
10.3
13.5
19.8
14.3
n.d.
21.8
n.d.
7.7
12.9
118
-------
Table 20 (Continued)
Start April 15, 1975
Site #
103
105
106
108
112
115
118
120
122
3 Mo.
"""
8.5
10.6
23.6
6.3
n.d.
21.4
n.d.
5.4
12.7
6 Mo.
9.0
10.2
17.6
7.4
n.d.
25.1
n.d.
5.3
9.4
12 Mo
10.8
11.1
15.6
10.1
n.d.
25.9
n.d.
6.8
10.4
15 Mo.
10.4
12.3
15.4
9.9
n.d.
21.9
n.d.
6.9
10.0
24 M
9 9
* »/
13.0
15.6
11.6
n.d.
17.6
n d
I 1 VJ
7.7
9.7
Start July 9, 1975
bite f
103
105
106
108
112
115
118
120
122
3 Mo.
9.5
9.8
11.6
8.5
n.d.
28.8
n.d.
5.2
6.0
6 Mo.
11.3
10.5
12.6
11.3
n.d.
36.7
n.d.
6.5
9.1
12 Mo.
10.9
12.7
13.3
10.8
n.d.
22.0
n.d.
7.3
9.4
21 Mo.
10 1
A V J.
13.4
14 5
«L i * \J
12 3
+ ^ * \j
n ri
1 1 U
17 0
* / \J
n d
* f (J
8 0
o . u
9.3
119
-------
Table 20 (Continued)
III. H2$ (ppb)
Start Nov. 10, 1974
Site #
103
105
106
108
112
115
118
120
122
3 Mo.
2.5
7.4
2.5
2.5
n.d.
2.5
n.d.
2.6
2.5
6 Mo.
2.9
10.1
2.5
8.2
n.d.
2.5
n.d.
2.7
2.5
12 Mo
5.1
11.0
3.7
6.4
n.d.
41.8
n.d.
4.4
3.7
24 Mo.
4.8
8.8
4.7
5.3
n.d.
42.4
n.d.
7.0
5.5
30 Mo
4.4
7.7
4.3
4.9
n.d.
34.4
n.d.
7.6
4.8
n.d - not determined.
Start Jan. 15, 1975
Site # 3 Mo. 6 Mo. 12 Mo. 24 Mo.
103 3.2 3.3 5.9 4.9
105 12.8 13.5 11.1 8.3
106 - 5.5 6.9 5.0
108 13.8 10.2 7.0 5.5
112 n.d. n.d. n.d. n.d.
115 - 2.9 83.0 43.2
118 n.d. n.d. n.d. n.d.
120 2.8 2.8 6.9 7.9
122 - 5.1 4.0 5.5
120
-------
Table 20 (Continued)
Start April 15. 1975
Site # 3 Mo. 6 Mo. 12 Mo 15 Mo. 24 Mo,
103
105
106
108
112
115
118
120
122
3.3
14.2
5.5
6.6
n.d.
2.9
n.d.
2.8
5.1
7.3
11.9
4.9
4.6
n.d.
61.4
n.d.
6.0
4.4
6.0
9.7
6.7
4.4
n.d.
67.9
n.d.
8.5
4.9
6.0
9.5
6.1
4.1
n.d.
57.1
n.d.
8.4
6.7
4.8
7.0
4.7
4.1
n.d.
38.4
n.d.
8.8
5.1
Start July 9. 1975
Site # 3 Mo. 6 Mo. 12 Mo. 21 Mo.
103 11.2 8.6 6.7 5.0
105 9.6 8.7 8.3 6.0
106 4.3 7.7 6.2 4.6
108 2.6 3.8 3.5 3.7
112 n.d. n.d. n.d. n.d.
115 120 123 70.7 43.5
118 n.d. n.d. n.d. n.d.
120 9.2 11.0 9.8 9.7
122 3.6 3.5 7.1 5.1
121
-------
Table 20 (Continued)
IV. Ozone (ppb)
Start Nov. 10, 1974
Site #
103
105
106
108
112
115
118
120
122
3 Mo.
7.1
7.8
6.6
9.5
7.6
12.5
17.0
9.2
15.7
6 Mo.
13.2
12.0
11.3
15.6
12.6
18.5
21.9
15.4
24.2
12 Mo
20.1
20.4
21.6
22.7
21.1
26.8
35.0
26.0
33.3
24 Mo.
23.2
22.7
23.4
25.9
23.0
30.5
36.6
27.1
35.3
30 Mo
22.5
20.8
21.6
24.5
21.6
28.8
34.2
25.2
33.3
Start Jan. 15. 1975
Site #
103
105
106
108
112
115
118
120
122
3 Mo.
19.2
16.3
16.0
21.6
17.7
24.5
26.8
21.5
32.8
6 Mo.
26.6
24.4
26.0
28.2
25.2
29.8
41.0
30.4
40.0
12 Mo.
21.4
21.2
23.3
25.3
22.2
28.6
36.5
27.2
34.7
24 Mo.
24.8
24.0
23.6
26.4
23.4
34.5
38.5
27.5
35.7
122
-------
Table 20 (Continued)
Start April 15. 1975
Site #
103
105
106
108
112
115
118
120
122
3 Mo.
34.1
32.4
36.0
34.9
32.7
35.1
55.3
39.2
47.3
6 Mo.
27.1
28.8
32.0
29.8
29.6
35.0
48.0
36.5
42.4
12 Mo
22.1
21.8
24.2
25.4
23.0
29.0
37.2
27.1
35.2
15 Mo.
24.8
24.6
26.0
27.8
25.2
31.6
39.4
29.4
37.7
24 Mo
24.9
23.0
24.2
26.7
23.8
31.4
37.3
27.7
35.6
Start July 9. 1975
Site #
103
105
106
108
112
115
118
120
122
3 Mo.
20.1
25.1
27.9
24.8
26.4
34.9
40.8
33.9
37.5
6 Mo.
16.0
18.0
20.6
22.4
19.3
27.4
32.0
24.1
29.4
12 Mo.
22.5
22.6
23.5
26.0
23.4
30.8
35.4
27.0
35.3
21 Mo.
23.6
21.7
22.5
25.5
22.6
30.9
34.8
26.1
33.9
123
-------
Table 20 (Continued)
V. NOX (ppb)
Start Nov. 10. 1974
Site # 3 Mo. 6 Mo. 12 Mo 24 Mo. 30 Mo,
103
105
106
108
112
115
118
120
122
41.3
49.8
40.3
36.5
44.0
20.4
41.7
35.4
10.7
31.0
52.1
45.5
34.1
43.8
18.0
17.0
33.8
9.6
31.3
46.4
42.9
31.9
46.4
16.9
14.6
31.5
8.6
38.9
47.6
49.7
35.0
48.4
17.4
14.7
32.4
10.4
40.6
49.7
51.2
36.3
43.8
18.6
15.7
34.1
10.5
Start Jan. 15, 1975
Site # 3 Mo. 6 Mo. 12 Mo. 24 Mo.
103
105
106
108
112
115
118
120
122
20.8
54.4
50.7
31.7
43.5
15.5
19.4
32.3
8.4
25.4
46.4
41.3
28.3
39.4
14.0
14.8
31.8
7.2
32.0
46.4
53.9
32.5
50.0
17.4
15.0
31.5
9.8
40.5
49.7
53.6
36.4
50.5
18.3
16.0
34.1
10.6
-------
Table 20 (Continued)
Start April 15. 1975
Site # 3 Mo. 6 Mo. 12 Mo 15 Mo. 24 Mo.
103
105
106
108
112
115
118
120
122
30.1
38.3
32.0
24.9
35.4
12.5
10.3
31.2
6.1
31.5
40.7
40.3
29.7
49.0
15.8
12.2
29.2
7.6
38.0
45.8
53.2
34.4
51.5
17.6
13.5
31.6
10.5
38.0
45.3
51.1
33.8
49.6
17.1
13.5
31.3
9.9
43.0
49.1
52.6
36.8
50.6
18.8
15.4
34.2
10.7
Start July 9. 1975
Site #
103
105
106
108
112
115
118
120
122
3 Mo.
32.9
43.1
48.6
34.5
62.5
19.1
14.1
27.2
9.0
6 Mo.
38.6
46.3
66.5
36.6
60.4
20.8
15.0
31.2
12.3
12 Mo.
40.0
47.0
55.9
36.0
53.1
18.2
14.3
31.2
10.8
21 Mo.
44.8
50.6
55.6
38.5
52.8
19.7
16.1
34.6
11.4
125
-------
Table 20 (Continued)
VI. THC (ppm)
Start Nov. 10. 1974
Site #
103
105
106
108
112
115
118
120
122
3 Mo.
1.56
2.29
1.84
1.93
1.76
1.41
1.38
1.72
1.74
6 Mo.
1.61
2.33
1.83
1.88
1.70
1.41
1.34
1.70
1.72
12 Mo
1.84
2.27
1.93
1.90
1.71
1.48
1.38
1.82
1.68
24 Mo.
1.94
2.26
2.07
1.99
1.83
1.57
1.52
1.86
1.73
30 Mo
1.93
2.28
2.10
2.00
1.90
1.63
1.59
1.89
1.72
Start Jan. 15, 1975
Site # 3 Mo. 6 Mo. 12 Mo. 24 Mo.
103
105
106
108
112
115
118
120
122
1.66
2.37
1.82
1.84
1.64
1.41
1.29
1.69
1.71
1.80
2.27
1.84
1.86
1.59
1.41
1.30
1.76
1.68
1.93
2.27
2.04
1.97
1.72
1.54
1.46
1.84
1.68
1.96
2.27
2.14
2.01
1.89
1.64
1.60
1.88
1.73
126
-------
Table 20 (Continued)
Start April 15, 1975
Site # 3 Mo. 6 Mo. 12 Mo 15 Mo. 24 Mo.
103
105
106
108
112
115
118
120
122
1.95
2.17
1.86
1.87
1.54
1.41
1.32
1.84
1.64
2.08
2.21
2.03
1.92
1.72
1.56
1.42
1.94
1.64
2.03
2.21
2.13
2.02
1.77
1.58
1.53
1.86
1.72
2.01
2.20
2.12
2.00
1.80
1.59
1.56
1.87
1.72
2.01
2.26
2.17
2.02
1.95
1.68
1.66
1.94
1.72
Start July 9. 1975
Site # 3 Mo. 6 Mo. 12 Mo. 21 Mo.
103
105
106
108
112
115
118
120
122
2.20
2.25
2.20
1.98
1.89
1.70
1.51
2.04
1.63
2.06
2.27
2.24
2.08
1.86
1.66
1.62
1.92
1.68
2.03
2.20
2.19
2.04
1.87
1.63
1.62
1.88
1.74
2.02
2.28
2.21
2.04
2.01
1.72
1.70
1.95
1.74
127
-------
Table 21a. Weighted Averages for Total Suspended
Participates
I. Start Nov. 10, 1974
Site #
103
105
106
108
112
115
118
120
122
3 Mo.
n.d.
6 Mo.
90.7
80.5
87.6
59.4
70.2
44.3
55.5
63.6
34.8
12 Mo.
105.2
91.4
90.3
81.6
89.3
65.3
85.6
84.7
57.8
18 Mo.
102.4
88.9
83.9
87.2
92.9
64.0
74.2
79.6
56.1
24 Mo
101.3
88.6
80.8
89.8
85.8
60.5
72.6
66.3
55.5
30 Mo.
96.5
87.5
79.1
86.6
80.4
58.7
68.1
63.6
54.2
n.d. - not determined.
II. Start Jan. 15, 1975
Site #
103
105
106
108
112
115
118
120
122
3 Mo.
90.7
80.5
87.6
59.4
70.2
44.3
55.5
63.6
34.8
6 Mo.
105.2
91.4
90.4
81.6
89.3
65.2
85.6
84.7
57.8
12 Mo.
98.8
85.4
78.7
81.1
82.1
58.7
69.6
71.8
51.8
24 Mo.
96.8
81.4
78.6
83.4
79.2
58.6
65.3
64.9
53.5
128
-------
Site #
103
105
106
108
112
115
118
120
122
Site
103
105
106
108
112
115
118
120
122
Table 21a (Continued)
III. Start April 15. 1975
3 Mo.
107.8
97.4
91.5
92.2
98.4
72.6
93.4
95.2
68.3
6 Mo.
3 Mo.
100.5
86.3
76.1
94.1
96.8
62.9
61.5
74.6
54.0
103.
90.
83.
93.
97.
66.
76.
82.
60.
IV.
1
8
2
2
5
7
5
8
7
Start
6
92
79
67
80
74
52
53
58
45
July
Mo.
.4
.3
.0
.6
.9
.2
.5
.8
.7
12 Mo
96.1
86.1
76.4
83.5
80.6
55.4
64.5
65.3
51.5
9, 1975
12
93
83
73
85
75
15 Mo.
95.8
86.2
77.1
86.7
80.5
57.1
71.4
62.9
54.1
Mo.
.5
.8
.2
.5
.9
54.2
61
55
51
.5
.0
.0
24 Mo.
95.2
87.7
77.6
86.8
78.5
57.7
67.1
60.3
54.8
21 Mo.
93.9
87.4
76.2
86.4
75.6
56.7
60.4
55.5
53.7
129
-------
Table 21b. Weighted Averages for Sulfate (yg/m3)
I. Start Nov. 10. 1974
Site # 3 Mo. 6 Mo. 12 Mo 24 Mo. 30 Mo.
103
105
106
108
112
115
118
120
122
n.d. 17.8
10.4
12.8
10.5
9.8
10.4
5.9
10.9
7.6
14.0
13.5
15.4
15.4
14.3
14.3
11.3
16.3
13.2
13.9
13.3
14.0
15.0
13.4
12.9
11.7
13.6
12.4
13.1
12.5
12.8
13.9
12.2
12.0
11.0
12.3
11.5
n.d. - not determined
II. Start Jan. 15. 1975
Site #
103
105
106
108
112
115
118
120
122
3 Mo.
17.8
10.4
12.8
10.5
9.8
10.4
5.9
10.9
7.6
6 Mo.
13.3
12.6
14.0
13.7
13.3
14.5
11.1
15.3
13.2
12 Mo.
13.1
12.4
13.5
14.1
13.0
12.7
10.9
14.0
12.1
24 Mo.
13.3
12.6
12.7
13.9
12.4
11.8
11.2
12.2
11.8
130
-------
Table 21b (Continued)
III. Start April 15, 1975
Site #
103
105
106
108
112
115
118
120
122
3 Mo.
12.5
13.8
14.5
15.2
14.9
15.9
12.4
17.5
15.7
6 Mo.
13.8
14.2
15.9
16.4
15.2
14.8
12.0
17.4
14.4
12 Mo
12.3
12.2
13.2
13.8
12.4
12.0
10.8
13.0
11.7
15 Mo.
12.7
12.6
13.2
14.0
12.5
11.9
11.0
12.8
11.7
24 Mo
12.9
12.4
12.4
13.7
11.9
11.4
11.1
11.6
11.4
IV. Start July 9. 1975
Site #
103
105
106
108
112
115
118
120
122
3 Mo.
14.5
14.4
17.1
17.4
15.5
14.1
11.6
17.3
13.3
6 Mo.
12.8
12.3
13.1
14.5
12.8
11.8
10.7
12.6
10.9
12 Mo.
12.5
12.2
12.5
13.7
11.9
11.2
10.6
11.3
10.8
21 Mo.
12.8
12.1
11.8
13.5
11.5
10.9
10.9
10.6
10.8
131
-------
Table 21c. Weighted Averages for Nitrate (ug/m3)
I. Start Nov. 10, 1974
Site #
103
105
106
108
112
115
118
120
122
n.d - not
Site #
103
105
106
108
112
115
118
120
122
3 Mo.
n.d
determined
3 Mo.
8.6
5.6
6.4
5.7
5.4
4.1
2.8
5.7
4.9
6 Mo.
8.6
5.6
6.4
5.7
5.4
4.1
2.8
5.7
4.9
II.
12 Mo
5.6
4.7
4.7
4.7
4.3
3.4
2.6
4.9
3.7
Start Jan. 15, 1975
6 Mo.
3.4
4.7
4.1
4.1
3.8
2.9
2.6
5.1
3.5
24 Mo.
4.8
4.4
4.2
4.3
3.9
3.5
2.9
4.1
3.8
12 Mo.
3.5
4.2
3.8
4.1
3.7
3.1
2.7
4.4
3.3
30 Mo.
4.6
4.3
4.1
4.2
3.8
3.6
3.0
4.0
3.9
24 Mo.
3.8
4.1
3.7
4.0
3.6
3.3
2.9
3.8
3.5
132
-------
Site I 3 Mo.
103 2.5
105 4.2
106 3.2
108 3.3
112 3.0
115 2.5
118 2.5
120 4.8
122 2.8
Site *
103
105
106
108
112
115
118
120
122
Table 21c (Continued)
III. Start April 15, 1975
3 Mo.
3.1
3.3
2.8
3.9
3.2
2.7
2.2
3.7
2.2
6 Mo.
2.9
3.7
3.0
3.6
3.1
2.6
2.3
4.1
2.5
IV.
12 Mo
3.5
4.1
3.6
3.9
3.5
3.8
3.0
4.0
3.3
Start July 9, 1975
6 Mo.
3.6
3.7
3.2
4.0
3.5
3.2
2.8
3.7
3.0
15 Mo.
3.5
4.0
3.6
3.8
3.4
3.6
2.8
3.7
3.2
12 Mo.
3.7
3.9
3.5
3.9
3.6
3.4
2.9
3.7
3.4
24 Mo,
3.7
4.0
3.5
3.8
3.4
3.5
3.1
3.6
3.3
21
3.*
4.(
3.!
3.5
3.!
3.<
3.:
3.(
3.(
133
-------
C£\
3- O
--( ^3-
> I
O
O
a-
c\j
O
01
ro
O
O
O
O
O
O
O
O
O
O
O
O
o
O
o
o
o
o
8
o
o
o
o
o
o
o
o
o
O
O
§
o
o
o
o
o
o
o
o
o
o
o
o
o
o
cn
o>
a:
134
-------
CO
CO
O
O
to
ro
O
O
CO
o
CO
o
CO
o
r-t r-.
^O^D
iILD
CO
o
ro
O
o
o
ro
O
O
o
o
O)
o
o
o
o
o
"3-
O
o
o
o
SI
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
cl
o
o
o
o
135
-------
oo
o
o
o
o
o
CM
Oil
CM ^H
Lf> CO
p~ O
r~- 00
O
00
CO
o
00
CO
01
c\jr^~
CXJCO
ii
o
~-(OU
r^cn
LOLD
^-*un
COLT)
i
o
o
o
o
o
o
o
C\J
o
CO
o
o
o
+
o
o
o
o
o
o
o
o
o
en
c?
o
o
CO
o
o
o
o
o
.4
o
o
o
o
o
01
o
o
IT)
o
c
o
en
01
C£
r-H CSJ
136
-------
O
O
CTi
VO^3-
-O
O
COPO
iO
i!
O
O
O
O
°l
\
O
O
O
O
O
O
O
O
^ 1XJ
O
O
O
O
O
O
O
O
O
O
s
O
Ol
O
O
LD
O
O
CM
ro
CO
137
-------
^H ro
c\jco
OJOO
CO
ro
O
O
lj_ CO U_ ^H
O )
CO
O
O
O
3-
T 1
O
O
0|
00
O
O
CO
O
O
O
O
O
O
O
O
.O
00
O
O
O
^-t
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
in
r-H CM
138
-------
ro
CO
10
o
o
o
o
o
o
o
01
r
o
rI 00
CO
CMOO OJ'.T>
CCX-I
ICO
ii
o
o
8
CO
o
o
o
o
o
o
CO
01
0)
cc
139
o
o
CO
o
o
o
o
o
o
en
o
o
o
o
o
o
o
o
o
o
o
o
CTi
o
o
CO
o
o
-------
o
o
CO
o
o
o
CO
.I
o
o
CO
o
o
OO H
o o
o o
o
o
o
o
OJ O
o
o
o
o
ol
o
o
o
o
o
o
Cxj
o
o
o
o
o
o
o
o
OJ
o
o
140
-------
o
o
CO
oo
o
o
0=1
o
o
o
o
00
CO
o
unin
0X0
>sn^
oxn
o
o
o
o
O
^H
O
o
o
o
10
o
o
o
o
o
o
3
r^ o
O O
CO 01
141
-------
0
s_
CD
C
CD
U
C(-
CD
O
o
E
O
CO
CD
C7>
CD
ro
.c:
-M
CO
r
CO
CD
.c
o
CL
>^
a:
M-
O
co
CD
t
OO
CM
CD
ro
*~
-jc
00 -X
0 -X
o
oo -x
0. -X
00 -X
1 -X
X
o
CO
o *
oo
CM
CM
o
oo i
oo
1 1
CT)
O -X
i -X
r
CD
CD
oo
-a
cu
N
.r
C"
ro
>
r
ro
C3
1
X
X
X
X
X
X
X
-X
X
X
X
jt
X
*
X
X
*
*
X
X
X
-X
X
*
r-
cu
CD
00
01
c
r~
S-
CD
4->
rO
CU
-X -X -X
X -X -X
X
X 1 -X
X
X -X
X -X *
X * -X
X -X -X
X -X -X
-X -X -X
X
X -X 1
X
X
X -X -X
X
X -X -X
-jc
X -X 1
X -X -X
X * -X
X -X *
CM CM <*
CD CD CD
CD CD CD
OO OO OO
-a en -a
CD C CD
N -i- N
r- S- !-
C CD C
ro -E rO
r~* ro *~~
ro CD ro
CI3 3 CO
X
y;
I -X -X -X
-X -X
X -X
X -X -X -X
X -X
X -X
X -X
1 -X -X -X
X
X -X
* -X
-X
X
X -X -X
X * -X -X
X
X -X
1 -V ^ 1
1 Tt TS 1
X -X
X -X
X -X
X * -X 1
X -X
X -X
X -X
X * -X 1
X -X
X *
X -X -X
"3-
CD
CD
oo ^ ^r
0> S_ 3 -C
c o o +->
- z: oo s-
s- o
CD " ^ ^
^= X X
4-> o> CD "
ro 4-> -f-5 c
CD ro ro -r-
3 -J I O
X
-X -X
X -X
-X -X
-X
X *
X -X
X *
X -X
X -X
X *
1 1
* -X
X *
T^ 1
X -X
X
1 -X
-X -X
-X -X
-x -x
fc "K
_£-
4->
3
0
oo o>
,
> J-}
r- S-
5 £
O
LO
ro
O O CO O LD
CD LT) I . CVi CT>
Qj
rO rO ro ro
o o o o u
C CD CD CD CD
C -Ti-3-1-3-1-3
ro CD CD CD CD
X -X
X * -X
I -X -X -X -X
142
-------
t/)
O
S-
O
^ t CTt
CO CO ro CNJ
CO CPi
QJ
4-*
OO
4->
CO
OJ
H-
q_
0
CD
c
CD c\j s. I r-, UD co ' en
> T3 '
4~) QJ !
f- (/i >-
on i i
^t r\j VQ ro co
1
QJ '
S !
L.
T3
s:
uD «* en CM r-.
!
4-J l/l !
c o
TJ z:
o_ o
CNJ ^-< 01 ro CO
CNJ CNI O> LO CO
QJ oo !
i^ _J ! v£> co r-. ro en
r3
0 Z
LO O-l OO ^<
O)
03
en to ex-
ro LO CO <i
un cO "-D
CO
o
143
-------
(/)
cr
o
CO
CO
rd
S_
O
O
o
Q-
01
c
OO
OO
O
u
o
OJ
-(-)
r-
oo
I LO
00
CO
OO
CO
CD
o
O)
-------
APPENDIX A
ADDITIONAL EXPOSURE TESTS
145
-------
CONTENTS
Figures 147
Tables 148
A. ALUMINUM ALLOY SHEET EXPOSED BY ALCOA 149
B. EXPOSURE OF CLIMAT DEVICES 150
C. ATMOSPHERIC WEATHERING TEST ON BRONZE SAMPLES 151
D. EXPOSURE OF ATMOSPHERIC CORROSION MONITORS (ACM) 152
References 154
146
-------
FIGURES
Number Page
Al ACM Data, December 1976 155
A2 t - Data Obtained Between October 1975 and March 1977 156
147
-------
TABLES
Number Page
AT Analyses of Hot Water Leach of Aluminum Alloy Sheet Panels
Exposed at Nine Sites in St. Louis, MO 157
A2 Type and Depth of Corrosion on 2014-T6 Sheet Panels Exposed
Three Months at Nine Sites in St. Louis, MO 158
A3 Type and Depth of Corrosion of Aluminum Alloy Sheet Panels
Exposed Two Years in St. Louis, MO 159
A4 Tensile Property Data of Aluminum Alloy Sheet Panels Exposed
Two Years in St. Louis, MO 160
A5 Summary of CLIMAT Results 161
A6 Average CLIMAT Values for Four Quarters 163
148
-------
APPENDIX A
ADDITIONAL EXPOSURE TESTS
A. ALUMINUM ALLOY SHEET EXPOSED BY ALCOA
At the start of the exposure test in October 1974 ALCOA personnel exposed
a number of Al alloys at all nine sites with the objective to evaluate weather-
ing of such materials and to analyze the deposits as an indicator of the pollu-
tants present on the Al tension samples. The test panels were 4 by 6 in. in
size and 0.063 in. thick. Five 20K-T6 panels and a single panel of 1160-H14
and 7075-T6 were exposed at each site. A set of 2014-T6 panels was returned
for evaluation after 3, 6, 12 and 24 months. The 1160 and 7075 panels were
returned after 24 months. After visual examination, panels from sites #103,
108, and 122 were retained for further analysis while the other panels were
re-exposed.
The panels which had been exposed for 3 months were analyzed by weight
-2
loss, determination of pH, C1-, NO- and SO. -content of a hot water leach of
the entire panel and metallographic determination of type and depth of attack.
For panels exposed for 6 and 12 months only the analysis of the hot water
leach was performed. Panels exposed for 24 months were examined by metal lo-
graphic observation, analysis of the hot water leach and a tensil test of
sheet-type tension specimens machined from the corroded panels.
The attempts to determine the weight loss after three months exposure of
the 2014 alloy were unsuccessful since a heavy black film was formed on the
sample when it was cleaned according to ASTM Gl-67. This film could not be
removed completely in a HNOo-rinse and some samples showed a weight gain. No
weight loss data are, therefore, reported.
The results obtained by ALCOA are shown in Tables A1-A4. It was concluded
that differences in the depth of attack at the various sites are small and not
significant (Table A2). As expected, pure Al panels incurred considerably
149
-------
less corrosion than Al 2014-TG anc /0/Ci-Tfj. 7he rate of corrosion of A1 2014-
T6 decreased markedly after the iivifel three iiionths of exposure. The results
of the tensile tests (Table AA) ,!-.'.,/ed no significant reduction in tensile
strength as a result of the two y^a^ exposure, There was a slight decrease in
elongation as a result :r;" rioter of1"r;clr: ""O!.: -;ir,^s. of corrosion. However,
even this was considered ~,o oa sl':ci,' and .inre'ioteo to the level of airborne
pollutants. Comments on ^hc- ^r-/1,.^";;'. or the ho: wc,t,rr leach (Table Al) have
been given in the previous report (5).
B. EXPOSURE OF CLIMAT DEVICES
Starting in April 1976 four sets of CLIHAT (Classification of Industrial
and Marine ATmospheres) devices were exposed on all nine test sites for a
period of 90 days. Al wire (0.9 M., in diameter and 900 mm long) is wound on
plastic, Cu or Fe bolts. From the percent weight loss of the Al wire a cor-
rosion index is calculated. Fro1/ die Al/nylon couple an atmospheric corro-
sion index (ACT) is derived, the .\;/Tc couple qives the marine corrosion
index (MCI) and a calculctec: ccn.cioati vi of the A'i/Fe and Al/Cu data provides
the Industrial corrosion incex {1C,;}. Results are shown in Tables A5 and A6,
which contain the average wvight loss and corrosion indices for the four
sets. Periods of no corrosion wero ,iot considered in the averages.
H. H. Lawson of ARMCO Steel Corp., l-nddletown, Ohio, who provided and
analyzed the CLIMAT samples, reached the following conclusions:
"Inspection of the tabular data cioei, not indicate any particular
trends with respect co the atmospheres at the sites. The signifi-
cant corrosion rates, wr.sre 01,served, appear to be random excur-
sions, and are scattered bsi^en the vdrious couple indices. In
general,, as might De expeclec,, tne fall/winter exposures are some-
what more severe, and che two 'extremity1 sites, 118 and "i22,
appear to be less corrosive rhaii the rest with respect to the
CLIMAT devices. Site 120 is probably the next least corrosive
site. It is difficult to dG^erni']^ th;j most severe site due to
the inordinate influence of trie excursions referred to earlier.
However, I would be inclined to call site 105 the most severe,
closely followed by 103, Sites 105 and 108 are comparable and
''50
-------
probably the next most severe. Although Site 115 appears to be
severe based on the averages shown in Table A6, this results from a
single datum point, the remaining indices being quite low. I would
rank the sites from severest to mildest as follows:
105, 103, 106, 108, 112, 115, 120, 118, 122
The St. Louis area does not seem to be particularly corrosive - at
least not to Al 1100."
It will be noted that failure of 100% of all Al tension samples at 25 Ksi
occurred in the shortest time at site #105 followed by #103, 122, 106 and 108.
All Al 2014 samples at 25 Ksi failed only at sites #105 and 108. Failure times
of the other samples also seem to be related to the CLIMAT results.
C. ATMOSPHERIC WEATHERING TEST ON BRONZE SAMPLES
This task was conducted by Prof. D. W. Zimmerman, Director of the Center
for Archeometry of Washington University, St. Louis, Mo.
Bronze plates were placed on the roofs of five RAMS stations in the
greater St. Louis area. The purpose was to observe and measure the rates of
corrosion of plates over a period of at least 2 years to provide fundamental
and vital data for the University's outdoor bronze monument conservation
program. Specific questions to be studied were:
1. Do wrought and cast bronzes corrode at different rates?
2. How does glass-bead peening (which is used to clean the statues)
affect the corrosion rate?
3. How does the alloy composition affect the corrosion rate?
Samp!es
Fourteen samples 2" x 3" x 1/4" were placed on each of the five sites.
Seven samples of each of two alloys: 85% Cu, 5% Sn, 5% Zn, 5% Pb; and 89% Cu,
11% Sn, were prepared as follows:
151
-------
1. Cast -- surface filed
2. Cast -- surface polished
3. Wrought -- surfaced polished
4. Wrought -- no surface treatment
5. Cast -- no surface treatment
6. Cast -- glass-bead peened
7. Wrought -- glass-bead peened
The samples were weighed before being set in place on April 15th and 16th,
1976, at sites #105, 108, 112, 120 and 122.
After one year of exposure, the results were as follows:
1. The primary effect was a darkening/tarnishing. Very little of
the basic green corrosion product has formed yet - only a thin
green veil over the "untreated" cast plate at site #122.
2. The 85-5-5-5 (Cu, Sn, Pb, Zn) alloy is darkening considerably
faster than the 89-11 (Cu, Sn) alloy.
3. The glass bead peened (the technique used for cleaning outdoor
bronze monuments) plates show the same or less darkening than
unpeened plates.
4. Areas peened a higher pressure (80-100 psi) and with larger bead
size (125 urn) show less tarnishing than lower pressure (4-60
psi) and smaller bead size (75 ym).
5. The highly polished, wrought plates show the least tarnishing.
6. No systematic differences between the five sites are apparent.
The outdoor test needs to be continued for at least another year;
other test sites are being evaluated for this program by Prof.
Zimmerman.
D. EXPOSURE OF ATMOSPHERIC CORROSION MONITORS (ACM)
The atmospheric corrosion monitor (ACM) described by Mansfeld and
Kenkel (1,2) consists of a Cu/Zn or Cu/steel couple which registers current
flow when electrolyte bridges the dissimilar metal plates. The electrolyte
might result from condensation of water from the air on corrosion products,
from dew or from rain. It has been shown (1-3) that the ACM data not only
measure the time-of-wetness of a test panel, but can also determine the
152
-------
corrosivity of a test site. Three ACMs were installed on October 3, 1975 at
Sites #103, 112 and 122; later an additional Cu/steel ACM was installed at
site #106. The ACM recording is stored in the RAMS/RAPS system; an evaluation
of some of these data is being conducted at the Science Center under an ONR
contract (4) which deals with basic mechanisms of atmospheric corrosion.
At present, only time-of-wetness t data have been determined from the
recorded ACM data as the hours per day during which the ACM signal exceeds
the background current which is flowing when the surface is dry. In Fig. Al,
ACM data are plotted for four sites in Decmeber 1976 as the sum of time-of-
wetness as a function of time. It can be seen that there are discontinuities
in the increase of t which reflect different climatic conditions. Between
w
December 21, 1976 and December 27, 1976 the ACM surface was dry at site #103.
At site #106 similar conditions occurred for about the same time period.
Surprisingly, the ACM at site #112, which is close to site #106, did not show
the absence of condensation, but instead a steep increase of the t -hours was
recorded. At site #122 no t -signal was received between December 20 and
December 31, 1976. In the following month 8.0 hours/day was measured as the
average t at site #122 indicating that the ACM was working properly. In
general, temperatures at site #122 were appreciably lower than at the other
sites.
Fig. A2 shows the t -data obtained between October 1975 and March 1977
for the different test sites. Several maxima and minima occur at similar
times for all test sites, although the absolute t -values can be quite dif-
ferent for the different test sites. For December 1975 the average values
fall between 49% for site #103 and 94% for site #122, which show that for an
accurate theoretical evaluation of corrosion behavior in atmospheric exposure
tests reliable time-of-wetness data have to be available in order to explain
the different corrosion results at various test sites. Average atmospheric
data such as daily average RH-values for a general area do not seem to be
sufficient to explain the reactions occurring in the microclimate of a test
site.
153
-------
REFERENCES
1. F. Mansfeld and J. V. Kenkel, Corr. Sci. 16, 111 (1976).
2. F. Mansfeld and J. V. Kenkel, Corrosion 33, 13 (1977).
3. F. Mansfeld, "Atmospheric Corrosion Rates, Time-of-Wetness and Rela-
tive Humidity, submitted to Werkstoffe and Korrosion.
4. "Electrochemical Studies of Atmospheric Corrosion," F. Mansfeld,
Principal Investigator, Contract No. 00014-75-C-0788 with Office of
Naval Research.
5. F. Mansfeld, "Study of the Effects of Airborne Sulfur Pollutants on
Materials", RAPS, Task Order No. 112, Contract No.-68-02-2093, Two-
Year Exposure Report, Rockwell International, AMC 7010T0112AR.
154
-------
400
DECEMBER, 1976
300
O Site 103 Cu/Zn 6.1 hrs/day
D Site 106 Cu/Zn 8.2 hrs/day
A Site 112 Cu/Steel 7.7 hrs/day
0 Site 122 Cu/Steel 1.5 hrs/day
I/)
200
100
Days
FIGURE Al. ACM DATA, DECEMBER 1976
155
-------
CTi
n:
CJ)
cc
LU
CQ
o
i
o
o
LU
LU
CQ
CQ
O
.
Q
I
-M
cr:
156
-------
r-
cu
.a
re
I
°
*
i/i
^
^
o
i
^J
00
c
r
Ol
OO
cu
C
r~~ """^
2: CM
C
1 » i i
CO
a ^r
ai
CO
O CM
a. E
X 0
UJ
to o
ai co
c
Q_ (/)
+-> 3
cu
CU "O
.c: a>
00 -C
o
>i *O
O O>
1 1
et re
ai
E s-
c
r- O>
E o
3 re
, M-
OO
0
.c
u
re
cu
s_
ai
4_J
re
c
in
i
o
X
CM
E
^^
cn
E
c
O
re
S-
4-j
c
cu
u
o
0
t
i
i
3
U
CM
CM
CU
£
O
CM
CU
lr-
00
00
,
r*
00
CM
f __
^_j
r
OO
CO
o
CD
+J
^-
CO
^o
o
QJ
4->
OO
LD
O
4->
OO
CO
o
QJ
r-
00
C
O
c
1J
3 -C
|g
j
>,
0
-I
Si
CO CO to
I r- O
V
CO CM CO
r l~- O
I I r
CM *3- in
1 CTt tO
* *
, r- O
CSJ CM tO
r*-» i co
« * i
i i O
^^
4-
^_^,
CO tO tO
LD CO CO
CSJ O O
en *^f to
to ai co
CM i O
CM CO CO
r*^ r r
i r r
ai in to
tO r- CO
CM CM O
CM O> tO
ai ^j- CM
in in CM
«-«*
OO OO OO
CO tO CM
1
to to to
1 1 h-
1 1 1
o o o
CM CM CM
in Q o
I^Q f^) ^3
o o o
i i i
i i i
i i i
i i i
i i i
i i i
i i i
i t i
i i i
i i i
i i i
i i i
i i i
i i i
i i t
i i i
O 0 O
o o o
o o o
1 1 1
1 1 1
1 1 1
1 1 1
1 1 1
1 1 1
1 1 1
1 1 1
T o in
CO O to
000
^<*
OO OO OO
d- <3- -xf
C\J CM CSJ
^~
{& LO r
t I :r
1 1 1
«3- LT) O
O O r-
oo r-^ i
1*0 fO o^ ro o^ oo
, CXJ r- , 0 r
0 O O O O 0
LO r-~ en i i i
C\J CSJ C\J 1 1 1
'111
o o o i t i
CO CTl <3~ 1 1 1
CSJ l CO | | |
1 1 1
O O O 1 1 1
CO P-- O"\ 1 1 1
i CSJ CSJ 1 t 1
'III
O O O 1 1 1
1>-_^ll
_J_
*^^f
r* ^-j- <^j- | | |
CSJ CO CO 1 1 1
111
O O O I 1 1
CSJ CSJ CO r- O
o o o o o o
to en en i i i
CSJ CSJ CSJ 1 1 1
III
O O O 1 1 1
CSJ O O 1 1 1
«3- LO . l
CM in CM r-» r-~ co
CM r~~ CM i r CM
o o c o o o
CM in to i i i
CO 1^ OO 1 1 1
-iii
o o o i i i
co to in i i i
^f co to i i i
-iii
o o o i i i
CM in co i i i
co r^ *j- i i i
-iii
O O O 1 I 1
. .
" - * (
- - u
K (C
in CM i i i cu
*3- to CM i i i i
i i i
O O O 1 1 1 "4-
V O
rn
a
to co to r in en
* O CO «* CO CM
O r O O O O
. .
*
in co i i i
CM to ^3- i i i
iii
O O O 1 1 1
V
CM in «* i i i
CM r--. to i i i
i i i
o o o i i i
_
^^
*
- -r--. in r o in
*3- ai to ^- to CM
O O 0 0 O O
V
CO CO CO CO CO CO
^y ^ -^ -^- -^^ ^
CO tO CM ^J- *^f ^J-
. CM CM CM
^3-
to to to to to i
1 1 1 h- 1 I
l 1 1 l 1 l
*d~ ^~ "^ *3~ in o
o o o o o r
CM CM CM CM f>. i
o o o
r O tO
in in in
o o o
«j- co cr>
in ^j- in
o o o
ai co to
>
«d~ ^J~ in
o o o
ai to r~-
«^- ^d" to
o o o
CT1 to 1
}
l
C
o
I/)
re
*
"C3
CU
JZ
re
cu
r
CU
i.
cu
u
re
14-
&_
13
OO
-f-
- '
157
-------
CM
CQ
^
4-^
*
O
OJ
CU
S-
.c
1
T3
CU
£
O
Q.
X
LjJ
(/) O
r- s:
CU
C "
(O U1
CX "r
^
4-^ O)
CU 1
CU
CO 4->
CO
tO
t E
1 -I
i l/l
O CU
CM 4->
C CO
O
CU
c c
O -r-
'<~~ ^L
0 4->
S_ (T3
O
( ^
4
O
-C
4->
cx
O!
a
X)
c
rti
CU
CX
H-
i.
i
o
(O
4->
||
*+~
0
-C
o.
01
Q
1
n
tJ
s-
ta
^:
S-
ro
LU
T3
s-
5
CO
0
r-
I/)
o
5-
O
0
14-
0
CU
a.
>-
h
4_i
t/1
CU
1
r^
.
ai
<-
.
X
(O
^~
>£_
,
X
^~
^_
S-
i
-i ^
s_
(T3
LU
-a
S-
(t!
3
to
CU
4->
(
co
COOl£3COCMCMi LOUD
o-iLncsirooooOLncocM
r CMCOCMt Or- i CM
ooooooooo
ooooooooo
idOtncnoocn^Ln
r*^ oo t**^ CM i~ *3~ r^ vo to
LnroLn^i-rooOi CMOO
ooooooooo
ooooooooo
LDCnCMCMCO«3-UDOOO
CMi i CMCMCMOOCOLn
OOOOCDOOOO
CDOOOCIOOOO
co co co co co co co
Q- D-
cx a. Q- D_ a. cx D-
1 1 I 1 1 t (1 1 1 1 <
CO CO CO CO CO CO
Q- D- Q-
CX. CX. Q_ D_ Q_ Q_ t/1
O)
.,_
CO
en
oounvococMLncoocM
OOOOf r r-CMCM i
to oo CM *
CM en oo *3-
OO , O CM
o o o o
o o o o
to oo en r^.
r^ i i^ en
LO OO i OO
o o o o
O O 0 C5
co CM en >^-
r~~- i o <£>
in CM i «d-
o o o o
o o o o
CO
i i i
i + i i
Q-
i I
CO
1 1 1
1 + 1 1
O-
cu
j^ en
en en 3: c
i- > O 03
T* <£ j ry
-i-
4-> r
r- CO
CX
II
II
1 1
D_ CO
a>
+J
O
~2Z.
158
-------
<4_
0 E
E
-C
M 1
CL
cu -*:
Q 0
ns
X -i->
n3 eg;
s:
-o
s_
ft3
^
.c
S-
o>
ro
CQ
3 O
C. I
r CO
t- -r-
O
C S-
O «3
r- CU
to >-
o
s- o
C5H?
o
(+_ CU
o to
o
-C Qj
P X
CLUJ
O to
"O CU
C C
tO ro
Q.
CD
CL
Q.
O)
r O
O O O
O O O
O
O
O
r 00 CO
r^ LO oo
o o o
o o o
O
O
r~ CM LT>
cr> un i
o o o
O O C3
o
O
o
CO I CO
I O
O I O
I
O I O
CO
o
o
CM ^J- CO
«3- co co
o o o
o o o
CO
o
00 CM «* CO
«* td- CM CO
o o o o
o o o o
o
CO
CL
Q.
o c
o
CU -r-
O. CO
>> o
h- s-
o
(O
CO
Q. Q- Q.
II Q_ II
s-
CU T-
CO 00 CM
O O CM
CO CO CM
O O CM
CT)
>
<
CO OO CV)
O O CM
CD
>,
o
o
vo
o
CM
LD
r^.
O
CU
4->
o
159
-------
CQ
^"
O
=t
.p+J
E c/j
>* 3
<=C r- E
< -r-
4- 00
O S-
03
ro QJ
-P >-
ro
Q O
. S
+J
S- T3
CU CU
CX CO
O O
S- Q.
CL. X
LjJ
CD
t/>
C
cu
,_
*««-*
1
Q.
s
CO'
00
.
1
1
]
1
1
CO
C o~5
O
oo
i O
in i
^
CD -C
r-~ -P
r- CT
co c
c cu
£=; 0) S-
CU 1 4-)
O)
VI
£-
QJ
co
113
i_
OO
1
CO
LO
N/ r
ro
p
Is
oo
r -
1
1 CM
9,5
O
1
r CT
cu c
r- QJ
OO
CO
LO
re! LO
Q.
2:
O
cu ~o
-P QJ
r CO
oo o
p
co
OJ
1
ex
X
QJ
C
13
vt-
>-
o
^~
,
et
i
:c
i
o
LO
1
I
O LO
O r
CD 00
F O
^J- CM
LO LO
r r-~
OO CM
,« |~~
r r
1 1
1 1
1 1
1 1
1 1
1 1
1 1
oo oo
0 0
f i
o
,
o
r~~
CM
LO
f
CM
t~
r
I
1
1
,
1
CM
CM
r.
1
1
1
1
1
1
1
O
^
LO
O
r-.
LO
CO
^
o
LO
_
CM
*
-a
cu
CO
O
Q.
X
CO
c
Z3
LO
1
1
r-.
O
CM
cn
i
CD
O
cn
cn
LO
CM
CO
=*
1
1
1
,
1
1
OO
o
cn cn
,_ ,
CD O
o o
CO r
cn o
LO r**-
oo
CO CO
vj- »a-
i i
i i
i i
i i
i i
i i
i i
CO CM
O CM
i i
1
1
1
1
;
1
1
O
^_
^
,_!
CO
oo
LO
LO
cn
CM
CM
O
LO
-a
CD
CO
o
Q.
X
QJ
ZD
LO
1
1
LO
p-^
O
r-.
CM
,
.
r-.
cn
,
,_!
CO
o
LO
LO
1
1
1
,
1
1
OO
0
,
cn cn
0 0
CD O
o o
r^ ,
i CM
co co
OO LO
LO LO
LO LO
1 1
1 1
1 1
1 1
1 1
1 1
CO CM
O CM
r i
i.
o
co
C
o>
r~
O
OJ
O-
CO O)
+->
d> ro
O- O
0> S-
O) 4J
jc c:
o cu
cj
O O>
ex
«^ co
x -a
O)
LO -o
t-- o
00 i,
s_
o o
o
3r CD
LO -I-J
o ro
u
O 'r-
" T3
CM CO
O 3
r- CT
X £Z
OO
LO CO
QJ
cn T-
-M
X S-
CD
oo ex
LO O
. S-
r- CX
CU
o
160
-------
Ln
LU
1
CO
1
P
co
CD
o:
-M
ro
O
O
S-
00
t t
CJ
1 1
_,
1 I
OL
oo
o
i i
H-1
5:
LU
Z
ce:
0
o
1 (
LU
a.
oo
O
oo co co r-- OOOIDO
i «d"OOi OOi P^O CMOOCOO
Z2IZZ ZZZZ ZZZZ
*d~ r^ CM ^i* i o Ln LQ Ln *±
td" CD r^v OO r r CO *3" CD r f^v CO
OCMCDO OOOO OOOO
LQooLnco r--.criLno CO^'^CM
LncooLn i i CMUD OCMI Ln
CM i i i
ZZZZ ZZZOO ZZZZ
i ^3- i OO IO i
O O O O CM O
OOOO OOOCM OOOO
CM CO r ^t CT> I
oooo oooLn oooo
oo
z z z
00 «d- CO CD
O i F^ VO
oooo
CM o r^ oo
i CM i O1
ZZZZ
^D *d~ F"""* CM
oooo
r-^ co P- CO
O CO i OO
2: z z z
CM CO
0 0
oooo
OO CM
0 0 O
zzzz
Ln o cri *3~
O i OO sj-
o o o o
r-~ «d- . CO
O i co VO
ZZZZ
i Ln i «d-
o i Ln CM
oooo
CM r O CO
O CM CO OO
ZZZZ
CO
o
oooo
CO
oooo
-o
a>
3
c
4-)
o
o
Q- CTl
t
LU '
a: i
ID I
OO CTt
O .
Q-
X
r 4-> C S-
3 O CO Q.
O CD >-3 <
E^+Jd
Q. 3 O CO
c£ r^) O '"D
4-> C t-
O CO CX
' o -D <:
S- r 4J C
Q. 3 U CO
ct rD O '"D
r 4J C S-
^3 O CO D.
-D O 1~D C i-
O co Q-
O -TJ <
l-i -M C
Q. 3 CJ CO
-M C S-
c_) co O.
o <-> -3:
r- >, . .
S- r- -M C
CL =J U CO
cC "O O -D
r- O
oo z
OO
o
Ln
o
co
o
CM
161
-------
1 1
CJ>
_J
OL
\
CO
Q
M
i
LU
" "* 1 1
"S £
O «ir
M
4-1
C
O
o
i_
r-
-(->
ro
DC
^Q
LO
00
O "
_J CT
4J
01
c
-M
^9
LO
O-~-
i r~ri
J w
3
z^zz: ^zzrz: zzzrz: z: 2:2:
CMcsjCM1^- rocooi~~- 001 en «3- r^'d"
, , roro i o«3-tM i i Ln i , i
OCDOO OOOO OOOO O OO
cor~-ocn o i CM t cou3r en LOOO
i i - Ln «3* CM i LO ^ i i en o i CM CM
z. S z: -z. 2:^2:^: ?-Z:H:^: z: z ^
i ooi r-«. LO r>. t co cOLn«a-co cri LDOO
. i OOCM i i OOCM Oi "=J-i O OOCM
OLOOO OOCDO OOOCD O OO
!MD<3-cnoo cMCOr^-oo i «d-tocn oo Lnm
i «^-rj-Ln CMCM«3-*3- i CMLDCvJ i LnOO
in
CQ
zr z:
ro]
O
t~*
o;
UJ
n:
D-
1/5
O ol
E
CM (JD i i
OOOO
OOOO
CO CO r CM
O CD O CD
o
o o o o
in
OOOO
r- CM co
0 0 O
0000
O OO «3-
r- O O O
o
0
o o
00
a
o
a;
UJ
a: vo
ZD r--.
co en
O r
Q.
X
UJ
O)
-I-1 £1 S-
O rO O.
O rT3 eC
S-
a.
4J C
o ro
O T>
4-> E i-
u ra Q-
o rr> =£
a. 3 o
<; t~D O 1
CO
>,
U ro Q.
O 0 <
O ro Q.
1 O r~O *^C
r- >, . . -r- >, . .
s-i -4->c: S-i 4->c
CLZSCJro Q_:3OrO
"<'~OO1-D , 5-
r CU
O) >
4-" QJ
CD ro rjj ro CO
r- i- i_ S_
O) O) QJ >,
o cu
QJ
S QJ
cu o
ii ii
z s; co
162
-------
CO O1 O
10 «3- n-
o «3- CM CM co to
3" CM CM CM CM i
O O O
OOO
000
CO
co
o-
cr
CTi <
o
O
to
o LO *^-
<~o ro co
^J- CM CM
CO «3- CM
C£
LlJ
I
o;
o-
o
u_
o
co r~~ CM
co oo oo
cri o 10
CO CM si"
oo < co
CM CM CM
o o o
CO
o-
en
cr
E
U3 LO O
CM in to
O O r-
co LO
ooo
LD co ,
CM
. o
ooo
ooo
ooo
o o
ooo
o
co
(/>
O-
^-i r COCOst LC)i£)
OCMCD C5OO OOO
o
z.
O)
COLOID COCMLn COOCM
OOO Oi i . CMCM
163
-------
TECHNICAL REPORT DATA
(Please read Instruction!, on the reverse before completing/
REPORT NO,
tPA-600/4-80-007
4 TITLE AND SUBTITLE
REGIONAL AIR POLLUTION STUDY
Effects of Airborne Sulfur Pollutants on Materials
|? AUTHOHIS)
I r. Mansfeld
3. RECIPIENT'S ACCESSION NO
REPORT DATE
January 1980
6. PERFORMING ORGANIZATION CODE
8. PERFORMING ORGANIZATION REPORT NO.
J3 FepFOriirflN'o ORGANIZATION NAME AND ADDRESS
s Rockwell International
J Environmental Monitoring & Services Center
| 11540 Administration Drive
1 crev- Coeur, MO 63141
j72~SPONSOfll\G AGENCY NAME AND ADDRESS
| Environmentdl Sciences Research Laboratory - RTP, NC
} Office of Research and Development
| ij.S. Environmental Protection Agency
j Research Triangle Park, N.C. 27711
No.TROGR'AM ELEMENT NO
1AA603 AA-126 (FY-79)
'15 SUPf LL'.'ifcNTArv NOTES
11. CONTRACT/GRANT NO
68-02-2093
Task Order 112
13. TYPE OF REPORT AND PERIOD COVERED
Final
14. SPONSORING AGENCY CODE
EPA/600/09
of galvanized steel, weathering steel, Al 2014 and 7079 stress samples, silver
nylon and two types of house paint were exposed at nine sites of the Regional
A-;r Monitoring System in the St. Louis area. Wind speed and direction, temperature,
dew point, total sulfur., SOz, HgS, 03, NO , total hydrocarbons, total suspended par-
Ticulcte matter, sulfate and nicrate were recorded.
For o/lvanized steel a pronounced effect of time of first exposure was observed. The
rorrcV.on behavior of weathering steel was not seasonally dependent. House paint show
edV^continuous erosive behavior. Exposure to the south was more erosive than ex-
posure to i-he i.orth. Rates for latex paint were higher than for oil based paint.
Thp erosion rate of marble decreased with time. At some sites 50% refectance oss of
M-jve- o.-curred after 3 months exposure. All samples of Al 7079 at 25 Ksi failed in
less then 255 days, while complete failure at 15 Ksi occurred between 277 and 630
days. For Al 2014 more scatter was observed.
:>, ,-.,.. n', ion levels in St. Louis were found to be rather low. Ozone showed similar
seastnai "changes as the temperature. Sites close to the center of St. Louis hadlower
070PP but higher NOX and total hydrocarbon levels. Sulfate was about twice as high inj
suimea as in winter* A first attempt at multiple regression anal^;s Jjas made^ Appa
PHI inconsistencies in the estimated effects are believed to be due to multicol linearity
'.17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
*Air pollution
Sulfur oxides
Su ifates
*Deterioration
wHigh strength steels
*Zinc coatings
J[AJ^mijium
DISTRIBUTION STATEMENT
RELEASE TO PUBLIC
*Silver
*Marble
*Nylon
*Paints
b. IDENTIFIERS/OPEN ENDED TERMS
COSATI I'lOld/Group
13B
07B
11F
11C
08G
111
19 SECURITY CLASS (This Report!
UNCLASSIFIED
21 NO OF PAGES
1.78
20 SECURITY CLASS (This pagej
UNCLASSIFIED
22 PRICE
EPA Form 2220-1 (Rev. 4-77)
PREVIOUS EDITION IS OBSOLETE
164
------- |