United States
Environmental Protection
Agency
Atmospheric Research and
Exposure Assessment Laboratory
Research Triangle Park NC 27711
Research and Development
EPA/600/S3-90/039 July 1990
&EPA Project Summary
Galvanized Steel - National
Distribution Study
J. Crouch and J. Catalano
The full report describes a field
survey done to observe the extent
and application of barge galvanized
steel in the United States. For
purposes, of the analysis, the
conterminous 48 states were grouped
into four regions. Industrial and rural
areas were considered in the study
which examined galvanized steel ap-
plications of roofing, siding, gutters
and flashing, transmission line
towers, fencing, pole line hardware,
guardrails, and storage facilities. A
field survey was conducted in four
cities thought to be representative of
each region for visual inventory. In-
house surveying was then performed
using aerial photography cor-
responding to the areas visited and
relevant land use data to calculate
surface area of the observed
galvanized steel. Extrapolation to
entire metropolitan areas was done
through the land use statisticcs.
Estimates of galvanized steel surface
in non-residential urban areas from
l:he survey observations are 9.2 xio4
m2 for Cleveland, 53.8 xio4 m2 for
Atlanta, 38.6xio4 m2 for Dallas, and
256.8xio4 m2 for Sacramento.
This Project Summary was
developed by EPA's Atmospheric
Research and Exposure Assessment
Laboratory, Research Triangle Park,
NC, to announce key findings of the
research project that is fully
documented in a separate report of
the same title (see Project Report
ordering information at back).
A field survey was done to determine
Ihe extent that bare galvanized steel is
used in the United States. Galvanized
steel is widely used for roofing, siding,
gutters, flashings, tramsmission line
towers, fencing, telephone pole hardware,
guardrails and storage facilities such as
sheds and warehouses. The survey was
done in four cities which were selected
as representative of the four major
geographic regions of the United States.
The four cities and the regions they
represented are: Cleveland, OH
(Northeast), Atlanta, GA (Southeast),
Dallas, TX (Central) and Sacramento, CA
(West). In the survey, the surface area of
the galvanized steel used in buildings,
towers, poles, fences and guardrails was
determined.
An initial selection of ground survey
areas was made from groupings of
industrial land use near the downtown
area and groupings of mixed
industrial/commercial or commercial land
use in the suburbs. In Atlanta, where no
large industrial concentration existed,
only mixed industrial/commercial sections
were visited.
Sections of 2 or 3 blocks to be
canvassed were selected upon arrival
within the survey area. Any structure
sighted with a galvanized coating was
sketched. Galvanizing was identified
from the material's characteristic coloring
and granular appearance of the surface
zinc crystals. The structure's position
was noted in relation to adjacent
landmarks and, if access was possible, a
photograph was taken along with a meter
rod for scaling. If not accessible, the
structure height was estimated and noted
on the sketch.
The emphasis was to cover as many
blocks as possible at the expense of
missing small amounts. USGS
topographical maps were obtained in
each city to confirm exact building
location. The sketch and photo were
used to show which surfaces of the
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building were galvanized as well as
building dimensions. All blocks visited
were counted as part of the area
surveyed, regardless of whether or not
galvanized steel was found.
Surface areas of galvanized steel were
calculated using the field notes and
photographs. Aerial photographs were
viewed under magnification to locate the
structure within the survey area and
obtain roof dimensions. These amounts,
by application, were multiplied by land
use area within the metropolis to obtain a
total for each land use category.
Galvanized steel usage on farms was
recorded by number of farms instead of
land use since a count of the number of
farms for 1985 was available. In this
survey, farm fencing was not considered;
the fence category for farms refers to
formed sheet- metal gates.
Extrapolation to entire metropolitan
areas was done through land use
statistics. Estimates of galvanized steel
surface in non- residential urban areas
from the survey observations are 9.2x104
m2 for Cleveland, 53.8x104 m2 for
Atlanta, 38.6x104 m2 for Dallas, and
256.8x104 m2 for Sacramento.
A comparison was made between the
results of this survey and those of two
other surveys of the material. One was
performed by TRC Environmental
Consultants and the other by the U.S.
Army Corps of Engineers, Cold Regions
Research Environmental Laboratory
(CRREL). The results of the CRREL
survey were summarized by Haynie
(Personal Communication, 1988) and
were used in the report.
A t-test procedure was used to
evaluate difference of means between
surface areas surveyed for roofing,
siding, fencing and "other" applications
and two other earlier surveys (CRREL
and TRC) covering rural and industrial
areas. With the exception of farm
fencing, no significant difference was
found at the 90% confidence level
between sample means. However, the
Aerocomp values tended to be lower;
partly due to the survey method, which
sometimes overlooked small surfaces.
On fencing, the CRREL survey recorded
plane surfaces, whereas Aerocomp
calculated the actual wire surface of
fencing. As noted earlier, perimeter
fencing on farms was not included in the
Aerocomp survey, so that a significant
difference exists for this application.
A survey was made of highway
departments of the 48 states to obtain
guardrail and fencing mileage.
Responses varied markedly. Some states
had the figures readily available whereas
others had never made a survey. Totals
for highway guardrail were received from
27 states, having a mean of 2694.5 km of
guardrail with a standard deviation of
2312.4 km. Predictor variables tested for
each region were population, highway
length, state area, land profile, and
average elevation of the state's highest
and lowest points. Only the Northeast
region showed some correlation with
population. For other regions, no
predictor proved significantly better than
a linear average.
The figures for fencing were even less
extensive than those for guardrails.
Highway fencing lengths were received
from 17 states with a mean of 3275.3 km
and a standard deviation of 3594.4 km.
The same predictor variables used for the
guardrail estimate were attempted.
However, only state area was significant,
at the 50% significance level. So, an
average of the fence values was used for
the estimate.
A small number of street fixtures in
Cleveland were galvanized poles; wooden
or painted poles predominated. Allpole
fixtures in Dallas and Atlanta were
painted or wooden. In downtown
Sacramento it was observed that a large
number of street fixtures were
galvanized.
Literature searches were made to
estimate transmission tower galvanized
steel surface. The Directory of Electric
Utilities supplied a sum of line length
nationally. Torpey and Lipfert in Methods
for Estimating Materials in Infrastructure
sampled typical transmission lines, giving
an estimate of the mean circuits per line
and percentage of steel towers. This
report gave a mean of the surface area
per tower resulting in regional estimates
of galvanized steel surface area in m3 on
transmission towers as follows Northeast
Region, 66.5x106, Southeast 62.2x106,
Central 25.2x106, West 44.0x106.
Comparison was made with
transmission line length in New York from
Torpey's work. The estimated length of
transmission lines for all utilities in New
York from the Directory of Electric
Utilities is 15,245 miles and a total
number of transmission towers in New
York was 57,925. This compares with
54,000 structures for New York in the
Torpey report.
An additional dataset was obtained
from Haynie on residential housing.
Galvanized steel amounts for both multi-
family and single family homes were
extracted from this dataset. These
studies sought to estimate the distribution
of exterior building materials in residential
areas by sampling in these cities and
comparing between the cities for usage
trends. The samples were taken from
single and multi-family housing units, and
the materials surveyed included paint,
masonry, stone, galvanized surfaces,
galvanized fencing, and a few other
miscellaneous materials. The average
amount of external galvanizing found per
building was 0.90 m2 for single family
dwellings and 0.07 m2 for multi-family
dwellings.
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J. Crouch and J. Catalano are with Aerocomp, Inc., Costa Mesa, CA 92626
Fred H. Haynie is the EPA Project Officer (see below).
The complete report, entitled "Galvanized Steel - National Distribution Study,"
(Order No. PB 90-215 799/AS; Cost: $17.00, subject to change) will be
available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Atmospheric Research and Exposure Assessment Laboratory
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
United States Center for Environmental Research
Environmental Protection Information
Agency Cincinnati OH 45268
Official Business
Penalty for Private Use $300
EPA/600/S3-90/039
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