United States
Environmental Protection
Agency
Risk Reduction Engineering
Research Laboratory
Cincinnati, Ohio 45268
Research and Development
EPA/600/S2-90/021 July 1990
EPA Project Summary
Preliminary Assessment of
Life-Cycle Costs of
Protective Clothing
Arthur D. Schwope
Many different types of chemical
protective clothing (CPC) are used to
isolate workers at hazardous waste sites
from contact with the potential hazards
posed by chemical wastes. The goal in
selecting the appropriate clothing for a
particular occupational situation is to
optimize worker protection and perfor-
mance while minimizing cost. Thisstudy
was performed to provide a more quan-
titative basis for making these chemical
protective clothing decisions. The study
examined the cost and quality factors
that influence the choice of CPC and
gathered data on different brands of CPC.
The research consisted of three analyses
conducted independently: a life-cycle
cost analysis; an analysis of the quality
of construction and sizing of Tyvekฎ*
coveralls; and a survey of U.S. Environ-
mental Protection Agency (EPA) and EPA
contract personnel to pinpoint research
and development needs for protective
clothing other than ensembles and
gloves. The study provides preliminary
information on the impact of various
factors on: clothing costs; the design,
quality, and sizing of a limited sample of
Tyvek coveralls; and the size, availabil-
ity, and use problems associated with
various types of CPC. Several actions'
that could be taken to provide users with
information useful for selecting appro-
* Tyvek is a registered trademark of The
DuPont Company. Mention of trade names
or commercial products does not constitute
endorsement or recommendations for use.
priate CPC are recommended. This is a
preliminary study to address the factors
that govern the choice of CPC. Many
assumptions were made and many of
the results are qualitative and based on
a limited sample size. More research is
needed to develop quantitative infor-
mation and to refine the analyses in the
study. Suggestions for future research
are provided.
This Project Summary was devel-
oped by EPA's Risk Reduction Engi-
neering Laboratory, Cincinnati, OH, 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).
Introduction
EPA emergency and hazardous waste
activities require the use of chemical protec-
tive clothing to ensure worker safety. The
term chemical protective clothing covers a
wide range of clothing, from ensemblesthat
encapsulate a worker's entire body, to splash
suits, to common work clothes with gloves
and boots. The purchase price of this
clothing varies widely from one type of
clothing to another and from one manufac-
turer to another. EPA and EPA contractor
personnel purchase CPC in large quantities
from different sources in many different
styles and sizes. Because of the number of
manufacturers as well as the range of CPC
prices, the choice of what type and brand of
CPC to buy is not simple. Too often the
purchase of CPC is made on the basis of an
insufficient understanding of the factors in-
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volved or wtth insufficient data at hand.
The principal pu rpose of this study was
to develop insights and preliminary data
about cost and quality factors that should
influence the choice of CPC. This research
consisted of three analyses, conducted in-
dependently: an analysis of the costs of
protective clothing over their life cycle; an
analysis of the construction and sizing of
limited-use clothing (specifically Tyvekฎ
coveralls); and a survey of EPA personnel
to identify research and development needs
in protective clothing areas other than en-
sembles and gloves (i.e., boots, overgloves,
face shields, and hoods). The methodol-
ogy, results, and conclusions of each of
these three studies are summarized herein,
beginning with the life-cycle cost analysis.
Life-Cycle Cost Analysis
Chemical protective clothing pu rchases
are based on several criteria, including pro-
tection, availability, and cost. This analysis
addressed only cost. All otherf actors being
equal, the clothing with the lowest cost is
preferred.
Some CPC is designed to be used
once and discarded. Other CPC may be
decontaminated and reused multiple times.
Therefore, cost per use, rather than pur-
chase price, should be used to compare
different clothing items.
Several factors influence the cost per
use, including purchase price and the costs
of decontamination, inspection, mainte-
nance, storage, and disposal. The life-
cycle cost study was performed to analyze
these factors and develop preliminary esti-
mates of the cost per use of clothing.
Methodology
Because little or no information, other
than purchase price, was available on which
to calculate the life-cycle cost of CPC, the
cost elements of decontamination, inspec-
tion, maintenance, storage, and disposal
were estimated on the basis of several
assumptions. These elements were then
combined and coded in BASIC to analyze
the effects of these various factors on cost
per use.
Results
The cost analysis showed that eight
factors contribute to the overall cost of
using protective clothing:
Cost to purchase
Number of times the clothing is used
Number of suits decontaminated per
day
Costs of decontamination
Cost of inspection
Cost of maintenance
Cost of storage
Cost of disposal
Additional factors would include perti-
nent logistical considerations and efforts
taken to ensure the effectiveness of the
decontamination process, but these were
not addressed in the study. In general, a
garment should be considered disposable
if its purchase cost is less than its average
cost per use for the anticipated number of
times it will be reused.
Specific trends apparent from the
study include:
The cost per use decreases as the
number of uses increases, except for
items with a very low purchase cost.
The cost per use decreases as the
number of items decontaminated per
day increases. The percentage de-
crease is less for items with a higher
purchase cost.
The cost per use increases as the cost
of labor increases.
As the labor cost increases, the num-
ber of items decontaminated per day
becomes less important.
As the purchase price increases, the
labor costs and number of items de-
contaminated per day become less im-
portant.
Under certain conditions, decon-
tamination and reuse of clothing should
not be considered. For example, item
s having a purchase cost of $10 or less
should always be discarded after a
single use.
Recommendations
Because of lack of cost data (except
purchase cost), this preliminary analysis is
intended to serve as a stimulus for further
investigations in the area, with the ultimate
goal being to provide adequate worker
protection at minimum cost. Future research
using parametric computer models is rec-
ommended to assess the sensitivity of the
life-cycle costs to changes in the assumed
decontamination costs. The validity of the
assumptions should be evaluated through
an external review. Then, the study con-
clusions should be implemented on a trial
basis at several waste sites to determine
the validity and deficiencies of the analysis.
The results would serve as the basis for
refining the model before its more wide-
spread implementation.
Quality and Sizing of Tyvek
Coveralls
In the past, price has often been the
sole criterion for selecting one brand of
protective clothing over another. The gar-
ments chosen, however, have often proved
inadequate because CPC quality does not
necessarily correlate with cost. For ex-
ample, the size and durability of garments
often vary greatly depending on the manu-
facturer. Some garments accommodate
winter clothing and hard hats, whereas
other garments of nominally the same size
from a different manufacturer do not. Dis-
posable garments that fit properly in some
areas (e.g., leg and body length) overwinter
clothing often prove too small in others
(e.g., chest and hips). Poorfit can stress the
garment and cause tears. A too long pant
leg could cause falls and too full sleeves can
snag on protrusions.
In this study, 12 Tyvek garments were
obtained from several sources and exam-
ined to highlight variations in their quality,
sizing, and cost. ~ln addition,'information
was gathered on (1) whether manufacturers
of disposable garments could manufacture
coveralls to alternative sizing specifications
and (2) the quantity and cost requirements
associated with such manufacturers. The
study was observational in character and
very limited in sample size. No physical
properties were measured and no statisti-
cal conclusions can be deduced or inferred.
Methodology
Two large-size Tyvek coveralls (one
Tyvek and one Saranex-laminated Tyvek)
were obtained from each of six manufac-
turers (including three relatively large-vol-
ume and three relatively small-volume
producers). These coveralls were exam-
ined for quality and size. The quality exami-
nations were based on visual examination
of uniformity, construction, quality, ease of
use, and potential for failure. No physical
properties were measured. The areas
studied were: seams, closures, zipperteeth
and slider, storm flaps, elastic cuffs, sleeves,
hoods, draw strings, and neck flaps. Spe-
cial attention was given to high-stress areas
such as the shoulder and crotch seams.
The size of each garment was assessed by
measuring it and comparing it with ANSI/
ISEA Specification 101-1985. In addition,
three major manufacturers of disposable
garments were contacted and asked
whether coveralls could be manufactured to
EPA-specified dimensions.
Results
The following design differences in the
clothing were noted:
The garments varied principally in
sleeve and seam type.
Some of the garments contained metal
zippers, others plastic.
The tightness of closure of the sleeves
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and pant cuffs varied among the gar-
ments.
The investigators reported the follow-
ing results and conclusions based on their
qualitative observations:
Quality and Cost
' The cost per garment does not corre-
late with apparent quality.
Some of the readily observed and
measured differences among the dif-
ferent coveralls relate to quality varia-
tions.
Saranex-laminated Tyvek garments
seem to be of higher quality than
Tyvek garments.
The manufacturers of higher-quality
., Tyvek garments dp not necessarily also
produce higher-quality Saranex-lami-
nated Tyvek garments.
There was no relationship between
garment cost and the size of its producer.
Sizing
NoneoftheTyvekgarmentsmet allthe
ANSI/ISEA standard minimums.
Saranex-laminated Tyvek garments
met the minimum specifications better
than did Tyvek garments. Two of
Saranex-laminated Tyvek garments
met all seven minimum dimensions for
size "large" garments as set by ANSI/
ISEA.
Two observations were made about
the ANSI/ISEA specification: (1) The
specification does not address three
dimensions of importance to garment
fit and ease of donning and doffing:
zipper length, hood width, and hood
length, and (2) Relatively high stan-
dard deviations were obtained for the
measurements of the Tyvek body length
and front opening length dimensions.
This result might be because the in-
structions in the specification fortaking
measuremments are inadequate.
Recommendations
The study of quality should be ex-
panded by examining a wider variety of
products from more manufacturers. The
garments should be evaluated quantita-
tively to provide a basis for purchase deci-
sions and to inform clothing producers about
EPA's needs. Field performance of the
garments should also be considered.
The study of sizing should also be
expanded by examining a wider variety of
products from more manufacturers. A labo-
ratory study and field trial should be con-
ducted, to define .the size, specifications
most appropriate for EPA field work. These
specifications should be reported to cloth-
ing producers so that they can improve
clothing design and fit.
User Survey
Methodology
In the third part of this study, CPC
users were surveyed to identify research
and development needs for CPC, exclud-
ing gloves and ensembles. A questionnaire
was sent to 235 EPA and EPA contractor
personnel involved in personnel protection
under Superf und. The questionnaire asked!
for information about problems encountered!
while using boots, overboots, gloves,
overgloves, aprons, faceshields, and
hoods. Users were asked to evaluate fit,
comfort, durability, effectiveness, and hin-
drances to mobility, as well as the availabil-
ity of size ranges and materials and the
number of sources for these items. Some
follow-up telephone calls were made to
obtain additional information.
Results
Results drawn from the telephone sur-
vey include:
There are insufficient ranges of sizes
for items such as boots, splash suits,
and coveralls.
For some clothing items, there are too
few sources and too limited availabil-
ity.
Some CPC items such as gloves fit
poorly.
Some CPC items have limited dura-
bility and functionality. Examples in-
clude the poortraction and durability of
overboots and the vision impairment
caused by faceshields and goggles.
Recommendations
The following recommendations were
made based on the preliminary survey:
Information in the brochures and avail-
able in a comprehensive format to field
personnel.
Manufacturers' literature should be
reviewed, and information on available
size from each vendor should be cir-
culated within EPA in the form of a
memorandum.
Publications such as Best's Safety
Directory and the Guidelines for the
Selection of Chemical Protective
Clothing should be circulated to users
so they will be aware of alternative
clothing sources.
Specific concerns about the durability
and functionality of certain CPC items
should be addressed in a laboratory
study.
The full report was submitted in fulfill-
ment of Contract No. 68-03-3293 by
Arthur D. Little, Inc., underthe sponsorship
of the U.S. Environmental Protection
Agency.
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Arthur D. Schwope is with Arthur D. Little, Inc., Cambridge, MA 02140-2390.
Esperanza P. Renard is the EPA Project Officer (see below).
The complete report, entitled "Preliminary Assessment of Life-Cycle Costs of Protec-
tive Clothing," (Order No. PB90-219 171/AS; Cost: $15.00; subject to change) will
be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Superfund Technology Demonstration Division
Risk Reduction Engineering Laboratory
U.S. Environmental Protection Agency
Edison, NJ 08837-3679
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati, OH 45268
BULK RATE
POSTAGE & FEES PAID
EPA PERMIT NO. G-35
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Penalty for Private Use $300
EPA/600/S2-90/021
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