EPA/600/R-10/002 | May 2010 | www.epa.gov/ord
United States
Environmental Protection
Agency
Material Demand Studies:
Materials Sorption of
Vaporized Hydrogen Peroxide
National Homeland Security Research Center, Office of Research and Development
U.S. Environmental Protection Agency, Research Triangle Park, NC 27711
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Material Demand Studies:
Materials Sorption of
Vaporized Hydrogen Peroxide
LAWRENCE R. PROCELL
ZOEA. HESS
DAVID G. GEHRING
JOSEPH T. LYNN
PHILIP W.BARTRAM
MARK D. BRICKHOUSE
TERI LALAIN
EDGEWOOD CHEMICAL AND BIOLOGICAL CENTER
RESEARCH AND TECHNOLOGY DIRECTORATE
ABERDEEN PROVING GROUND, MD
SHAWN RYAN
BRIAN ATTWOOD
NATIONAL HOMELAND SECURITY RESEARCH CENTER
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
RESEARCH TRIANGLE PARK, NC 27711
G. BLAIR MARTIN
NATIONAL RISK MANAGEMENT RESEARCH LABORATORY
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
RESEARCH TRIANGLE PARK, NC 27711
I National Homeland Security Research Center, Office of Research and Development
I U.S. Environmental Protection Agency, Research Triangle Park, NC 27711
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Disclaimer
The findings in this report are not to be construed as an official Department of the Army or U. S.
Environmental Protection Agency position unless so designated by other authorizing documents.
If you have difficulty accessing this PDF document, please contact Kathy Nickel (Nickel.Kathy(@,
epa.gov) or Amelia McCall (McCall. Amelia(@,epa. govl for assistance.
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Foreword
Following the events of September 11, 2001, EPA's mission was expanded to address critical
needs related to homeland security. Presidential Directives identify EPA as the primary federal
agency responsible for the country's water supplies and for decontamination following a chemical,
biological, and/or radiological (CBR) attack.
As part of this expanded mission, the National Homeland Security Research Center (NHSRC) was
established to conduct research and deliver products that improve the capability of the Agency in
carrying out its homeland security responsibilities. One specific focus area of our research is on
decontamination methods and technologies that can be used in the recovery efforts resulting from a
CBR contamination event. In recovering from an event and decontaminating the area, it is critical to
identify and implement appropriate decontamination technologies. The determination and selection
of an appropriate technology depends on many factors including the anticipated impacts on materials
and equipment, costs, logistics of application, waste generation, and health and safety.
This document provides specific information to aid in deciding on the appropriateness of a particular
decontamination agent: vaporized hydrogen peroxide (VHP®). Past large-scale use of the fumigant
resulted in a significant difference between anticipated and actual VHP® generation requirements
necessary to achieve the target hydrogen peroxide concentration in the enclosed space. This was
believed to be due to the consumption of hydrogen peroxide vapor by materials in the facility.
The study undertaken provides results of the demand (or consumption) that the resident materials
(walls, carpet, etc.) exhibit for hydrogen peroxide when used to cleanup areas following chemical
or biological contamination. This information is useful to help determine fumigant generation
requirements and cleanup strategies for facilities.
These results, coupled with additional information in separate NHSRC publications (available at
www.epa. gov/nhsrc). can be used to determine whether a particular decontamination technology
can be effective in a given scenario. NHSRC has made this publication available to assist the
response community prepare for and recover from disasters involving chemical and biological
contamination. This research is intended to move EPA one step closer to achieving its homeland
security goals and its overall mission of protecting human health and the environment while
providing sustainable solutions to our environmental problems.
Cynthia Sonich-Mullin, Acting Director
National Homeland Security Research Center
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Preface
To address Homeland Security needs for decontamination, the U.S. Environmental Protection
Agency (EPA) established an Interagency Agreement with the U.S. Army Edgewood Chemical and
Biological Center (ECBC) to take advantage of ECBC's extensive expertise and specialized research
facilities for the decontamination of surfaces contaminated with chemical and biological (CB)
warfare agents. The EPA's National Homeland Security Research Center (NHSRC) collaborated
with ECBC to determine the impact of vaporized hydrogen peroxide (decontaminant) on indoor
surfaces in buildings. The vaporized hydrogen peroxide work was completed under EPA IAG D W
939917-01-0. The work was conducted from November 2003 to July 2005 and recorded in ECBC
laboratory notebooks 05-0059, 04-0043, and 05-0044.
The use of either trade or manufacturers' names in this report does not constitute an official
endorsement of any commercial products. Manufacturer names and model numbers are provided for
completeness. This technical report may not be cited for purposes of advertisement.
This report has been approved for public release. Registered users should request additional copies
from the Defense Technical Information Center; unregistered users should direct such requests to the
National Technical Information Service.
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Acknowledgments
The authors thank the following individuals for their contributions toward the successful completion
of this test program. The authors thank Mr. Dave Stark for completing the independent audits per
the EPA program requirements. The authors also thank Dr. David Cullinan for preparing many
coupon run baskets, performing coupon measurements and preparing chain-of-custody forms during
the time his assigned laboratory was closed. The authors thank Mr. Dave Sorrick for assistance with
acquiring materials and equipment fabrication. The authors thank Ms. Diane Simmons for assistance
with the issuance of this report. The authors thank Dr. Emily Snyder, Dr. Zhishi Guo and Mr. Leroy
Mickelsen for reviewing and commenting on the final report.
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Contents
1.0 Background 1
2.0 Summary of Conclusions 3
The conclusions reached in this study are summarized below 3
3.0 Introduction 5
4.0 Experimental 7
4.1 Representative Building Material Test Coupons 7
4.2 Hydrogen Peroxide Test Chamber 9
4.3 Material Demand Testing 10
4.4 Data Review and Technical Systems Audits 11
4.5 Material Demand Calculation 12
5.0 Evaluation of Empty Chamber 13
5.1 "Fog" Test Results and Discussion 13
5.2 Baseline Tests and Results 13
5.3 Baseline Test Discussion 17
6.0 Evaluation of Building Materials 19
6.1 Results 19
6.2 Discussion 34
6.3 Consequences for building decontamination 36
7.0 Quality Assurance Findings 37
8.0 Challenges and Lessons Learned 39
8.1 VHP® Relative Humidity Sensors 39
8.2 Calibration of Drager Hydrogen Peroxide Electrochemical Sensors 40
9.0 References 41
Appendix A: Detailed Coupon Preparation and Inspection Procedures 43
Appendix B: Coupon Identifier Code 47
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List of Figures
Figure 3.1: The Steris VHP® Decontamination Cycle 6
Figure 4.1: Samples of the Test Coupons 8
Figure 4.2: ECBC Exposure chamber 9
Figure 5.1: Exposure chamber Fog Test 13
Figure 5.2.1: Illustration of the Determination of Zero Time 14
Figure 5.2.2: Baseline VHP Exposure Tests 15
Figure 5.2.3: Concentration Profile for Baseline VHP Exposure Tests 16
Figure 5.3.1: VHP Process using a Baseline Test 17
Figure 6.1.1: Chamber Temperature Profile throughout Testing 19
Figure 6.1.3: Representative VHP Test Results for Carpet 21
Figure 6.1.4: Representative VHP Test Results for Steel 22
Figure 6.1.5: Representative VHP Test Results for Painted Gypsum Wallboard 23
Figure 6.1.6: Representative VHP Test Results for Acoustical Ceiling Tile 24
Figure 6.1.7: Representative VHP Test Results for Wood 25
Figure 6.1.8: Representative VHP Test Results for Concrete Cinder Block 26
Figure 6.1.9: Representative Concentration Profile Results for Carpet 28
Figure 6.1.10: Representative Concentration Profile Results for Steel 29
Figure 6.1.11: Representative Concentration Profile Results for Gypsum Wallboard 30
Figure 6.1.12: Representative Concentration Profile Results for Acoustical Ceiling Tile 31
Figure 6.1.13: Representative Concentration Profile Results for Wood 32
Figure 6.1.14: Representative Concentration Profile Results for Concrete Cinder Block 33
Figure 6.2.1: Aeration Time for Building Materials Exposed to 250-ppmv VHP 35
Figure 8.1: Comparison of VHP Concentration and %RH 39
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List of Tables
Table 4.1: Representative Building Interior Materials 7
Table 4.3: Coupon Exposed Area 10
Table 5.2: Baseline Material Demand Test Results 14
Table 6.1.1: Material Demand Results for Building Materials (125-150 ppmv) 27
Table 6.1.2: Material Demand Results for Building Materials (250-300 ppmv) 27
Table 6.3.1 Material Demand of Warehouse Surfaces 36
Table 6.3.2 Material Demand of Office Surfaces 36
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List of Acronyms and Symbols
A surface area
APG Aberdeen Proving Ground
ASTM American Society for Testing and Materials
Ave average
b As a subscript in Section 4.5, the baseline tests
CB chemical and biological
CoC chain of custody
cfm cubic feet per minute
CT concentration multiplied by time
CT, t CT of the affluent
inlet
CT,. _, difference in CT , t and CT , t for the baseline tests
diff,b inlet outlet
CTdiSk difference in CTmlet and CTouflet for a specific material after baseline correction
CT ,t CT of the effluent
outlet
dH202 density (g/L) of H2O2 at 30 °C using PV = nRT
doc documentation
DS Decontamination Sciences
ECBC Edgewood Chemical and Biological Center
EOR end of run
EPA U.S. Environmental Protection Agency
Ftotel total volume defined by test limits (0 - 1000 ppmv-h)
h height
GSA General Services Administration
H2O2 hydrogen peroxide
hr or hrs hour or hours
IAW in accordance with
IOP Internal Operating Procedure
IS internal standard
ISO 17025 International Standardization Organization Standard 17025 on Laboratory Quality
Procedures
1 length
J mass flux
mb specific material
MD material demand
min minutes
MH202 mass of hydrogen peroxide
NHSRC U.S. EPA National Homeland Security Research Center
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Psys chamber pressure
ppb part per billion
ppmv part per million by volume
QA quality assurance
QAPP Quality Assurance Project Plan (QAPP)
QMP Quality Management Plan
RH relative humidity
SOP(s) standing operating procedure(s) (standard may also be used in place of standing
with the same meaning)
Std dev standard deviation
T temperature
t time
SOR start of run
TIC(s) toxic industrial chemical(s)
TIM(s) toxic industrial material(s)
TR technical report
TSA technical systems audit
U.S. United States
UV ultraviolet
Ver version
VHP® Steris' registered "vaporized hydrogen peroxide" procedure
w width
COUPON SPECIFIC CODING
"W" bare wood
"R" carpet
"T" ceiling suspension tile
"G" latex-painted gypsum wallboard
"S" painted structural A572 steel
"C" unpainted concrete cinder block
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MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
1.0
Background
The Material Demand effort was designed to determine
how building materials impact the ability to maintain
a target decontaminant vapor concentration within an
enclosed interior space. The building materials may
impact the decontaminant vapor concentration by either
sorption or decomposition of the decontaminant. Since
building interiors may contain large surface areas
consisting of different materials, data are needed to
determine how these interior surfaces affect the ability
to maintain a stable target concentration. Vaporized
hydrogen peroxide (VHP®) and chlorine dioxide (C1O2)
were selected since these decontamination technologies
have been used to decontaminate indoor surfaces
contaminated by anthrax and/or show potential for use
in decontaminating indoor surfaces contaminated by
chemical agents. Vaporized hydrogen peroxide (VHP®)
results are presented in this report. The representative
building interior materials tested were unpainted
concrete cinder block, standard stud lumber (wood 2"x
4", fir, type-II), latex-painted '/i-inch gypsum wallboard,
ceiling suspension tile, painted structural steel and
carpet.
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MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
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MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
2.0
Summary of Conclusions
The conclusions reached in this study are summarized
below.
• The VHP® Material Demand tests showed that the
building materials affect the VHP decontamination
vapor concentration. The impact varies based on the
type of material.
° The concrete cinder block coupon had the greatest
impact on maintaining the VHP® concentration
due to decomposition of the VHP®.
° The cellulose-based materials, wood and ceiling
tile, showed adsorption of the VHP® with a high
material demand value approximately one-third to
one-half the value for concrete. VHP® desorption
resulted in a long aeration time.
° The wallboard had a moderate effect on the VHP®
concentration compared to concrete cinder block.
° The carpet and steel coupons had a low impact
on the VHP® concentration compared to concrete
cinder block.
• The relative humidity sensor measurements were
affected by the presence of VHP®. The sensor
read high in the presence of VHP®, but responded
normally with no apparent visual degradation after
the VHP® was removed.
The hydrogen peroxide sensor performance
verification using the wet-chemical titration method
showed that both the inlet and outlet sensors were
not adversely affected by prolonged and repeated
exposure to VHP®. Neither of the two sensors
showed evidence of visual deterioration or change
in response during the testing period.
Hydrogen peroxide concentration sensor calibration
using sulfur dioxide in nitrogen gas revealed that the
sensors were highly sensitive to changes in pressure.
For the custom built exposure chambers, inline
sensor calibration is recommended.
The percentage of VHP® decomposition in the
chamber was a function of VHP® / air flow through
the chamber. A VHP®/air flow of 3.0 ft3 / min was
used in all tests.
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MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
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MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
3.0
Introduction
To address Homeland Security needs for
decontamination, the U.S. Environmental Protection
Agency (EPA) established an Interagency Agreement
with the U.S. Army Edgewood Chemical and Biological
Center (ECBC) to take advantage of ECBC's extensive
expertise and specialized research facilities for the
decontamination of surfaces contaminated with
chemical and biological (CB) warfare agents. The
EPA National Homeland Security Research Center
(NHSRC) formed a collaboration with ECBC in
a mutual leveraging of resources, expanding upon
ECBC's ongoing programs in CB decontamination to
more completely address the parameters of particular
concern for decontamination of indoor surfaces in
buildings following a terrorist attack using CB agents,
toxic industrial chemicals (TICs) or materials (TIMs).
Vaporized hydrogen peroxide (VHP®) and chlorine
dioxide (C1O2) are decontamination technologies that
have been used to decontaminate indoor surfaces
contaminated with anthrax and show potential for use
in decontaminating indoor surfaces contaminated by
chemical agents. This program is specifically focused
on decontamination of the building environment, for
purposes of restoring a public building to a usable
state after a terrorist attack. Systematic testing of
decontamination technologies generates objective
performance data so building and facility managers,
first responders, groups responsible for building
decontamination, and other technology buyers and users
can make informed purchase and application decisions.
Since building interiors contain a large surface
composed of different materials, the Material Demand
effort was designed to determine how building materials
impact the concentration of decontaminant in the vapor
phase. The objective of this study was to establish
and conduct laboratory test procedures to determine
to what degree building materials affect the vaporized
decontaminants. The building interior materials used
for testing are a subset of the variety of structural,
decorative and functional materials common to
commercial office buildings regardless of architectural
style and age. The building materials encompass
a variety of material compositions and porosities.
The materials studied included unpainted concrete
cinder block, standard stud lumber (wood 2"x 4", fir),
latex-painted '/2-inch gypsum wallboard, acoustical
ceiling suspension tile, primer-painted structural steel
and carpet. The focus of this technical report is the
evaluation of the building interior materials and VHP®.
The VHP® technology developed by Steris (EPA
registration #58779-4) has been in use for more than
a decade. The VHP® fumigant was initially used to
sterilize pharmaceutical processing equipment and clean
rooms.1'2 In response to the anthrax attacks of October
2001, Steris adapted its VHP® technology to perform
the decontamination of two U.S. government facilities,
the General Services Administration (GSA) Building
410 at Anacostia Naval Base, Washington DC, and the
U.S. Department of State SA-32 "Sterling, VA" mail
center. Through a joint venture with Steris Corporation,
the application of vaporized hydrogen peroxide (VHP®)
and modified VHP® for chemical- and biological-
agent decontamination have been successfully tested
in laboratory, large-chamber and field demonstrations
including a former office building and a C141 aircraft.3"5
Vaporized hydrogen peroxide (VHP®) also reacts with
and neutralizes VX and HD chemical agents.6
Decontamination of an interior space using VHP® is a
four-phase process involving preparation of the building
interior air (dehumidification), achieving a steady state
decontaminant level (conditioning), performing the
decontamination, and then aerating for safe reentry
(Figure 3.1).3
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MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
Figure 3.1: The Steris VHP® Decontamination Cycle
1. Dehumidification
— 2. Conditioning
<§
3. Decontamination
HnO
H
4. Aeration
Time
Dehumidification
Hydrogen peroxide vapor can co-condense with water
vapor producing an undesired condensate high in
hydrogen peroxide. If ambient conditions are likely
to permit condensation - high humidity and/or cold
temperatures - this condensation can be prevented by
circulating dry, heated air through the interior prior to
injection of the hydrogen peroxide vapor. The target
humidity level is determined by the concentration
of vapor to be injected and the desired steady state
concentration for the decontamination. The lower
relative humidity permits a higher concentration of
hydrogen peroxide without reaching a saturation point.
For this study, the maximum relative humidity at start-
of-run (prior to introducing decontaminant) was 30%.
Conditioning
During the conditioning phase, the injection of hydrogen
peroxide vapor is initiated at a rapid rate to the desired
concentration set point without condensation. Once the
target concentration is achieved, the injection rate is
lowered to maintain the set-point concentrations.
Decontamination
Decontamination is a timed phase dependent on the
hydrogen peroxide vapor concentration. In building
and aircraft applications a decontamination timer counts
down from the preset decontamination time. If the
concentration or temperature values fall below the set
point, the timer stops. Stopping the timer ensures that
during the decontamination phase, the interior space
is exposed to at least the minimum decontamination
conditions for the desired exposure time. For
this laboratory-scale study, the enclosure VHP®
concentration was maintained uninterrupted within the
target concentration range.
Aeration
After completion of the decontamination phase, the
hydrogen peroxide injection is terminated. Air is
introduced into the chamber. The air displaces the
hydrogen peroxide. The system is monitored until the
hydrogen peroxide concentration falls to a safe level for
coupon removal.
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MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
4.0
Experimental
The Material Demand testing was conducted in
compliance with the Quality Assurance Project and
Work Plan (QAPP)7 developed under the Quality
Management Plans (QMP)8-9 and EPA E4 quality system
requirements.5'10"12
4.1 Representative Building
Material Test Coupons
Test coupons were prepared in accordance with
the ASTM testing requirements for the Material
Compatibility testing.13 The coupons were cut from
stock material in accordance with the procedure in
Appendix B of the QAPP7 and reproduced as Appendix
A of this report. Coupons were prepared by obtaining
a large enough quantity of material that multiple test
samples could be obtained with uniform characteristics
(e.g., test coupons were all cut from the interior rather
than the edge of a large piece of material). The building
materials studied, including supplier and coupon
dimensions, are provided in Table 4.1 and shown in
Figure 4.1.
Chain of Custody (CoC) cards were used to ensure
that the test coupons were traceable throughout all
phases of testing. The test coupons were measured
and visually inspected prior to testing. Coupons were
measured to ensure that the test coupon was within the
acceptable tolerances (Appendix A). Coupons were
visually inspected for defects and/or damage. Coupon
measurements and visual inspection were recorded
on the CoC card. Coupons that were not within
the allowable size tolerances and/or damaged were
discarded. Each coupon was assigned a unique identifier
code that matched the coupon with the sample, test
parameters, and sampling scheme (Appendix B). The
unique identifier code was recorded o n the CoC card.
The CoC cards followed each sample from Material
Demand testing through Material Compatibility testing
to disposal.
Table 4.1: Representative Building Interior Materials
Material
Structural Wood, fir
Latex-Painted Gypsum Wallboard
Concrete Cinder Block
Carpet
Painted Structural Steel
Ceiling Suspension Tile, Acoustical
Code
W
G
C
R
S
T
Supplier
Home Depot
Home Depot
York Supply
Home Depot
Specialized Metals
Home Depot
Length
10.0 in
6.0 in
4.0 in
6.0 in
12.0 in
5.3 in
12.0 in
Width
1.5 in
6.0 in
8.0 in
8.0 in
2.0 in
0.8 in
3.0 in
Thickness
0.5 in
0.5 in
1.5 in
0.0 in
0.3 in
0.3 in
0.6 in
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MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
*Coupons are not shown to scale
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MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
4.2 Hydrogen Peroxide Test Chamber
APlas-Labs compact glove box (Model 830-ABC) fitted
with Hypalon® gloves and glove port plugs was used as
the Exposure Chamber (Figure 4.2). The glove box is
acrylic with an internal volume of 11.2 cubic feet (28"
w x 23" d x 29" h) with an isolated transfer chamber
that is 12" long x 11" diameter (ID.). The chamber
was insulated with 0.5-inch thick polyisocyanurate
foam insulation (R value 3.3) to help stabilize exposure
temperature and minimize possibility of VHP® or water
condensation (insulation not shown in Figure 4.2). The
chamber insulation blocked exposure of VHP® to light
and minimized possible VHP® decomposition. An
exposure rack constructed of Lexan® and horizontal
stainless steel bars was used to hold the test specimens.
The exposure rack was 12" long x 12" wide x 24"
tall and had four levels in which to place specimens.
Coupons were placed in the glove box in accordance
with IOP DS04016 as shown in Appendix B, Figures B.I
and B.2.
The vapor concentration, temperature and relative
humidity were recorded each minute during testing.
The VHP® concentrations were measured using two
Drager hydrogen peroxide electrochemical sensors
(model HC 6809070) coupled with Drager Polytron 2
transmitters for real time monitoring at the inlet and
outlet of the chamber. The sensors were placed in small
enclosures attached directly to the inlet and exit ports
of the exposure chamber. The inlet detector measured
the hydrogen peroxide concentration immediately
before entering the enclosure. The hydrogen peroxide
concentration within the chamber was measured by the
exit detector immediately after the effluent exits the
chamber. The sensors were factory preset to measure
from 0 to 4000 ppmv H2O2 with sensitivity < ± 5% of
the measured value, but were recalibrated in-line using
VHP® concentration values determined by chemical
titration of VHP® captured in bubbler solutions. The inlet
hydrogen peroxide detector was calibrated to measure
from 0 to 800 ppmv H2O2, and the outlet hydrogen
peroxide detector was calibrated to measure from 0 to
340 ppmv H2O2IAW IOP DS04001.
Sensor operation was verified during each run using
the average value from three iodometric titrations on
the VHP® stream entering and exiting the glove box
(IOP DS04019). A Vaisala HUMICAP temperature
and humidity sensor transmitter (model HMT333)
was placed in the center of the chamber. The relative
humidity sensor accuracy was ±1% at 0 to 90% RH
and ±1.7% at 90 to 100% RH (non-condensing). The
temperature sensor operating range was - 40°C to 80°C
with an accuracy of ±0.20°C. The sensor data were
collected electronically using a portable data logging
system manufactured by Omega Engineering (OMP-
MODL). The data were transferred to a PC running the
Omega supplied Microsoft Windows based HyperWare
software for data plotting, real time trending and initial
analysis. An Omega OMP-MLIM-4 expansion module
was used to monitor output from the device. Data were
collected at a rate of at least one data point per minute.
Sample rack loaded with
concrete coupons
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MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
VHP® was generated using a Steris VHP® M100-S
hydrogen peroxide vapor generating system and 35%
hydrogen peroxide. Airflow and peroxide solution feed
rate were controlled using a Siemens OP-7 interfacing
unit. The desired flow rate and peroxide feed rate were
entered into the interfacing unit. The VHP concentration
ranges for this testing were 250 to 300 ppmv and 125
to 150 ppmv. The bottle containing hydrogen peroxide
was not weighed before and after each test so the mass of
decontaminant consumed was not recorded. The VHP®
decontamination technology requires relatively low
humidity conditions to reduce the likelihood of peroxide
condensation. The low humidity was maintained
by drying the air with a Munters MG90 desiccant
dehumidifier before it was fed into the VHP® delivery
system. The humidity of the air fed into the VHP®
delivery system was < 30% relative humidity at the
start of test. The humidity of the air in the test chamber
was typically < 15% relative humidity. Exposures
were carried out with a minimum 30 °C temperature.
Temperature, humidity and hydrogen peroxide
concentrations were continuously monitored during
the decontamination process. The off gas from the
chamber was decomposed and released into a chemical
fume hood. VHP® was catalytically decomposed to
water and oxygen in a Random Technology catalytic
converter containing metal catalysts (platinum and
palladium) on an aluminum honeycomb monolith
substrate. The chamber was operated IAW SOP RNG-
107, IOPDS04015, and IOPDS04016.14-16 ADrager
Pac III single gas monitor fitted with a Drager hydrogen
peroxide sensor was used to monitor the VHP® outside
the chamber in the workspace. The standard measuring
range of the VHP® monitor is 0 to 10.0 ppmv H2O2 with
a display resolution of 0.1 ppmv.
A small recirculation fan was used in the chamber to
mimic the air circulation provided by fans in commercial
large room decontamination. Air circulation was
observed using a "fog" test of dry ice and warm water
rather than a "smoke" test. There was concern that the
smoke test might leave residue inside the chamber that
could interfere with the coupon studies.
4.3 Material Demand Testing
Each material type was tested independently in three
replicate trials at both the target and half-target VHP®
concentrations. The number of test materials was
dependent on the coupon surface area. The Material
Demand test used the appropriate number of coupons
so that the total surface area exposed to vapor was
essentially the same for each coupon type. The sample
surface area was calculated by summing the area for
each exposed sample face. For example, the wood
surface area is (2 * 1 * w) + (2 * 1 * h) + (2 * w * h). The
testing was conducted in accordance with the procedures
documented in SOP RNG-107 and lOPs DS04015 and
DS04016 and as shown in Appendix B, Figure B.l.14'16
The hydrogen peroxide sensor performance was verified
before testing in accordance with IOP DS04015.
Deh umidification
The coupons were exposed to decontaminant in accordance
with section 6.0 of the Material Demand QAPP17 The
coupons were placed in the exposure chamber in
accordance with IOP DS04016.16 The chamber humidity
was adjusted below 30% relative humidity using air flow
from the dehumidifier prior to the introduction of VHP®
into the glove box. The time required to adjust the
humidity in the chamber was between 15 to 30 minutes.
Table 4.3 Coupon Exposed Area
Material Code
Structural Wood, fir
Latex-Painted Gypsum
Concrete
Carpet
Painted Structural
Steel
Ceiling Suspension
W
G
C
R
S
T
Sample Dimensions (cm)
length
25.4
15.2
10.2
15.0
7.8
15.0
30.0
width
3.9
15.2
20.3
20.0
5.2
2.0
8.0
height
1.3
1.3
1.4
0.6
0.6
1.4
Sample
Surface Area*
(cm2)
270
539
495
600
267
586
Coupons
per Test
18
9
10
8
18
8
Total
Area
(cm2)
4863
4854
4952
4800
4798
4691
Vapor per
Sample Area
(cm3/cm2)
65.2
65.3
64.0
66.1
66.1
67.6
' Sample surface area is calculated for each exposed sample surface
** Volume chamber is 11.2 cubic feet (317,148 cubic cm)
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MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
Conditioning
VHP® was introduced into the chamber to reach the
target 250 ppmv or half-target 125 ppmv concentration.
Once the measured VHP® concentration reached the
target concentration, the decontamination phase was
started.
Decontamination
The VHP® concentration within the chamber was
maintained within the target concentration range of
250- to 300 ppmv or the half-target concentration range
of 125- to 150 ppmv. The CT (chamber concentration
multiplied by time) values for the target and half-target
concentrations were made the same by running the
half-target concentration tests for twice the time of the
target concentration tests. During Reliability Tests
with the VHP® system, the initial residence time of
vaporized hydrogen peroxide in the chamber at 0.2 CFM
(requested by the EPA) was determined to be longer than
the decomposition half-life. The concentration of VHP®
at the outlet detector was only 20% of the concentration
measured at the inlet detector. After consultation with
Steris, the chamber was fitted with larger diameter
tubing to allow increased flow through the chamber, and
therefore a faster turnover rate. Further characterization/
reliability tests (1 to 6 cfm) showed that increasing the
flow through the chamber minimized the difference in
the VHP® concentrations at the inlet and outlet detectors.
The flow rate (3.0 cfm) through the chamber was chosen
to optimize for both residence time and decomposition
of peroxide. The flow rate was documented in the
Quality Assurance Project and Work Plan (QAPP).7
The flow rate provided a turnover of approximately
sixteen exchanges per hour in the chamber. The flow
rate was fixed at 3 cfm for each stage (dehumidification,
conditioning, decontamination, and aeration) of the
Material Demand tests. The temperature during
exposure was kept above the minimum requirement of
30 °C. The hydrogen peroxide sensor performance was
verified at least once during each test by comparison to a
wet-chemical titration method.
Aeration
Aeration of the chamber was conducted following the
decontamination period. The VHP® concentration
within the chamber was monitored until end-of-
run (EOR). EOR was defined as the reduction of
chamber concentration to 10% of the decontamination
concentration. For the VHP® studies, EOR was
approximately 15 ppmv for half-target or 30 ppmv for
target concentration runs. Aeration of the chamber
continued until the vapor concentration fell to or below
the levels required by the ECBC Risk Reduction Office
to assure safe operation for personnel. The procedures
for the safe opening of the chamber and coupon removal
after fumigant exposure are documented in SOP RNG-
107 and IOP DS04015. Low-level vapor monitors were
used for monitoring personnel. A Drager Pac III single
gas monitor fitted with a Drager hydrogen peroxide
sensor was used to monitor the VHP®. The standard
measuring range of the VHP® monitor is 0 to 10.0 ppmv
H2O2 with a display resolution of 0.1 ppmv.
4.4 Data Review and Technical
Systems Audits
The approved Material Demand QAPP specified
procedures for the review of data and independent
technical system audits. All test data were peer reviewed
within two weeks of generation. The project quality
manager (or designee) was required to audit at least 10%
of the data. In addition, the project quality manager
(or designee) performed four technical system audits
over the course of testing. A technical system audit is
a thorough, systematic, on-site qualitative audit of the
facilities, equipment, personnel, training, procedures,
record keeping, data validation, data management and
reporting aspects of the system. The QA findings are
documented in Section 8.0.
4.5 Material Demand Calculation
The difference in the target chamber CT (CTouflet, in
ppmv-hr) and the inlet CT (CTinlet, ppmv-hr) required
to achieve the target (1000 ppmv-hr) can be attributed
to the demand of the material in the chamber for
VHP®. This demand is comprised of reversible
adsorption (e.g., physisorption) and chemical reaction
(e.g., decomposition or chemisorption) on the surfaces
within the chamber. A contribution of homogeneous
decomposition may also be present; however, efforts
were made to minimize the contribution of this
mechanism (e.g., rapid turnover rate and shielding from
UV). A correction must be made for the hydrogen
peroxide remaining in the chamber at the end of the
fumigation period. This correction factor, CTchaige, was
determined by multiplying the volume of the chamber
by the concentration in the chamber at the end of the
fumigation period and converting it into terms of ppm-
hrsby Equations.
The impact of each material on the required CT (CTaff k)
can be determined by subtracting the observed difference
in CT in the baseline tests (CTdiffb) from that observed
with a specific material type in the chamber (CTdiffmb),
shown in Equation 1. It is important to note that while
during a fumigation in the field the CT is generally
not calculated until the target concentration has been
reached, for the purposes of this research the calculated
CT begins at the time injection is started in order to
account for any sorption occurring prior to reaching the
target concentration.
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
CT.... = CT ..„ . - CT..... = (CT , - CT., - CT. ) . -
diffjc diff,mb diff,b v outlet inlet charge^mb
The time and surface area specific material demand
over the fumigation period (up to 1000 ppmv-hr) can
be calculated according to Equation 2 where CT^^
is divided by the material surface area (A, in m2) and
the time required to reach the target CTouflet (t, in hr).
The units of MD are ppmv-hr per hr per m2. The total
surface area added to the chamber for each material type
is reported in Table 4.3. The total interior surface area of
the chamber and material support structures was 3.8m2.
CT
- (for materials), MD = - -
tA
- (for baseline) (2)
The calculation of the material demand via Equation 2
provides for a determination of the relative effect of each
material on the chamber VHP® concentration.
The Material Demand is also reported in g/m2/h for the
chamber (Table 5.2) and the materials (Table 6.1.1 and
Table 6.1.2). The mass of VHP® decomposed or sorbed
by a specific material, MH202k (g), was calculated from
the CTsffmband CTsffb by Equation 3.
The baseline correction was required since CT,. _ ,
" diff,mb
included homogeneous decomposition and the material
demand of the interior of the exposure chamber and the
material
The average and standard deviation of each specific test
were calculated using Microsoft Office Excel (2003)
SP2 software. The determination of statistical outliers
was performed according to the Grubb's test, also known
as the extreme studentized deviate (BSD) method. No
data was discarded as an outlier within a data set (i.e., set
of triplicate experiments at each concentration for each
material).
CT . MWH
ppmv-hr -"
1000RT
(3)
Where:
MWH202 is the molecular weight of hydrogen
peroxide, 34 g/g-mole
Ps s is the chamber pressure in atmospheres
Tsys is the chamber temperature in K
Ftotel is the flow rate through the chamber, 5097 L/hr
R is the universal gas constant (0.0826 L atm/g-mole K)
The mass flux for the baseline tests, Jb (g/m2/h) was then
calculated using Equation 4.
(4)
The mass flux for each material, Jk (g/m2/h), was
calculated by Equation 5.
(5)
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
5.0
Evaluation of Empty Chamber
5.1 "Fog" Test Results and Discussion
A "Fog" test was conducted to observe the chamber
air circulation pattern created by the chamber
recirculation fan. The test was conducted with an
air flow of 3.0 cfm through the chamber. The small
recirculation fan was used in the chamber to mimic
the air circulation provided by fans in commercial
large room decontamination. The fan was placed
on the bottom of the chamber in the back right
corner. The fan blew toward the opposite corner
of the chamber. The "Fog" test was used to verify
that the coupons placed on the exposure rack had
contact with decontaminant vapor during testing.
A container of dry ice and warm water was placed
in the chamber. The fog produced could be
sustained for several minutes. Air was introduced
into the chamber on the lower right side of the
chamber and the flow observed. Figure 5.1 shows
the photographs taken of the fog test within the
exposure chamber. The density of the fog was hard
to photograph; however, the fog developed an even
density and did not stratify.
5.2 Baseline Tests and Results
Three baseline tests were conducted at the target and
half-target concentrations for the determination of VHP®
loss due to spontaneous decomposition and/or adsorption
and decomposition from the chamber interior surfaces.
The results of those tests are presented in Table 5.2. No
coupons were used in the baseline tests. The sample
rack was in the chamber during the baseline tests. The
air flow rate during the baseline tests was 3.0 cfm.
The hydrogen peroxide sensor performance was verified
during testing using a wet-chemical titration procedure.
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
For the first three test runs, the titration was performed
at the beginning-, middle- and end-of-run. After the
first three tests, the titration was performed during
the first half of the run. Three replicate samples were
collected and titrated. The average agreement between
the hydrogen peroxide inlet sensor reading and titration
results for the nine titration tests performed for the
target and half-target VHP® runs was 4.2% and 4.8%,
respectively. The average agreement between the
hydrogen peroxide outlet sensor reading and titration
results for the nine titration tests performed for the
target and half-target VHP® runs was 3.5% and 3.8%,
respectively.
Zero time on all graphs signifies the time where the
VHP® concentration within the enclosure first reached
the minimum value of the concentration range; either
250- or 125 ppmv (Figure 5.2.1). Based on the
four step VHP® process, zero time is the start of the
decontamination phase.
Figure 5.2.1: Illustration of the Determination of Zero Time
Vapor Concentration Throughout Run
Baseline Exposure at 250-300 ppm (7Jun05 run)
Concentration, Enclosure —Concentration, Feed —Concentration Limits
Vapor Concentration throughout Run
Baseline Exposure at 125-250 ppm (7Jun05 run)
-0.5
0.5
1 1.5
Time (hour)
2.5
Table 5.2 Baseline Material Demand Test Results
Test
Baseline
(125-150 ppmv)
Baseline
(250-300 ppmv)
Average
Chamber
32.5 ±1.3
32.8 ±0.1
Average Feed
151.2±3.2
326.4 ±6.7
Time to
reach
target CT
(hr)
7.47 ±0.16
3.73 ±0.08
DCT
(ppmv-hr)
128.3 ±4.6
199.2 ±9.8
MD
(ppmv-hr/hr/
m2)
4.18±0.16
13.90 ±0.66
Jb
(g/hr/m2)
0.0272 ±0.0014
0.0896 ± 0.0046
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
Representative VHP® 125- and 250 ppmv baseline test
CT graphs are shown in Figure 5.2.2. The CT within
the chamber and the CT of the feed air are shown in
gray and black, respectively. The feed concentration
was adjusted as needed to maintain the chamber
concentration within the target concentration range
(Figure 5.2.3).
Figure 5.2.2: Baseline VHP Exposure Tests
a) CT of Baseline Exposure at 250-300 ppm (23May05 run)
CT Throughout Run
CT, Enclosure
— CT, Feed
1500
1250
1000
^fSfr
a.
>
500
259
-1
Time (hour)
b) CT of Baseline Exposure at 1 25-1 50 ppm (7Jun05 run)
CT Throughout Run
CT, Enclosure
~CT, Feed
1500
^t25fr
1000
750
-500-
250
-1
45
Time (hour)
10
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
Figure 5.2.3: Concentration Profile for Baseline VHP Exposure Tests
a) Concentration Profile for Baseline Exposure at 250-300 ppm (23May05 run)
Vapor Concentration Throughout Run
— Concentration, Enclosure ^Concentration, Feed — ^conc. limits
a
a.
|
O
a.
soe
Time (hour)
b) Concentration Profile for Baseline Exposure at 125-150 ppm (7Jun05 run)
Vapor Concentration Throughout Run
— Concentration, Enclosure —Concentration, Feed —cone, limits
4 5
Time (hour)
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
5.3 Baseline Test Discussion
The baseline test results showed minimal hydrogen
peroxide loss due to spontaneous decomposition and/
or adsorption and decomposition from the chamber
interior surfaces at 3 cfm. The hydrogen peroxide sensor
performance showed good agreement with the wet-
chemical titration results.
The dehumidification step was conducted prior to the
start of data collection. Data collection began with
the introduction of fumigant into the chamber during
the conditioning phase. Once the VHP® concentration
reached the target concentration, the feed rate was
reduced and the decontamination phase began. In the
field, the cumulative CT calculation would not begin
until this point. However, in this study the CT was
calculated at the start of hydrogen peroxide injection
into the chamber, resulting in an exposure less than
what would be experienced in the field. An attempt to
correct this discrepancy by extrapolating the data out to
a true CT of 1000 ppmv-h, showed that the difference
was not statistically significant. Because the difference
was insignificant the results reported in this document
are based on starting the CT calculation at the start of
injection. The feed concentration was reduced to zero
once the target CT had been reached by immediately
stopping the liquid peroxide injection into the VHP®
generator. Once the liquid peroxide injection was
terminated, the decontamination phase ended and the
aeration phase began (Figure 5.3.1). The immediate
termination of liquid hydrogen peroxide injection
resulted in the sharp flattening of the feed CT curve
(Figure 5.2.2). The enclosure CT did not immediately
flatten. The enclosure CT continued to rise at a slower
rate after reaching 1000 ppmv-h due to flow rate and
chamber volume. The enclosure hydrogen peroxide
concentration decreased as the VHP® was diluted with
the input air.
Data for CT curves were collected until the VHP®
concentrations within the chambers dropped to <10%
of the decontamination concentration. The difference
between the feed CT and enclosure CT curves is due
to loss of VHP® within the enclosure. Loss of VHP®
during the baseline test could result from spontaneous
VHP® decomposition, VHP® decomposition on chamber
surfaces and/or surface sorption. To minimize potential
loss due to condensation, the chamber, sensor enclosures
and tubing were wrapped with insulation and maintained
above 30 °C. Similarly, potential losses due to light
exposure can also be neglected. The chamber, sensor
enclosures and tubing were either opaque or wrapped
with opaque insulation.
Figure 5.3.1: VHP Process using a Baseline Test
CONDIT
(L
.
Vapor Concentration Throughout Run
Baseline Exposure at 250-300 ppm (23May05 run)
— Concentration, Enclosure — Concentration, Feed —cone, limits |
ONING
2
'" | 1
jlrt DECONTAMINATION I AERATION
M •
, VVV«A ,
0 I - VsJS^*>W' -"A— ^•^
/
V
1 _
101234567
Time (hour)
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
6.0
Evaluation of Building Materials
6.1 Results
The VHP® Material Demand chamber exposure tests
were conducted from February through June 2005. The
exposure chamber temperature profile was maintained
within a small range of 30 - 35 °C throughout testing
(Figure 6.1.1).
The Vaisala HUMICAP humidity sensor (model
HMT333) read slightly high in the presence of VHP® at
approximately 300 ppmv, but when removed from air
containing VHP® the sensors responded normally with
no change in response. Since the relative humidity
constraint was for the condition of the chamber prior
to the introduction of the fumigant, the condition
was satisfactorily met with the sensors. Additional
evaluation of the relative humidity sensors is provided in
Section 8.1.
The hydrogen peroxide sensor performance was also
verified on each material exposure run using the wet-
chemical titration procedure. The titration was performed
during the first half of each run. Three replicate samples
were collected and titrated. The average agreement
between the hydrogen peroxide inlet sensor reading and
titration results for the eighteen titration tests performed
for the target and half-target VHP runs was 6.5% and
3.2%, respectively. The average agreement between the
hydrogen peroxide outlet sensor reading and titration
results for the eighteen titration tests performed for the
target and half-target VHP runs was 5.4% and 4.2%,
respectively. The hydrogen peroxide sensor performance
verification procedure conducted during each run
showed that both sensors were not adversely affected by
prolonged and repeated exposure to VHP®. Neither of
the two sensors showed visual evidence of deterioration
or change in response during the testing period.
Representative CT graphs for each of the test materials
are shown in Figures 6.1.3 through 6.1.8. Each graph
consists of two CT curves. The enclosure CT (gray line)
reflects the hydrogen peroxide CT within the chamber.
The enclosure CT determined the test run duration. The
concentration of the enclosure was maintained during
the decontamination phase within either the target or
half-target concentration range. The feed CT (black line)
shows the hydrogen peroxide CT from the generator.
During the decontamination phase, the generator feed
concentration was adjusted to maintain the chamber
within the target or half-target concentration range.
Figure 6.1.1: Chamber Temperature Profile Throughout Testing
Temperature Profile Throughout Run
All VHP Exposure Tests
-20-
-W-
-1 0
4 5
Time (hour)
10
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
The Material Demand contributions attributable to each
of the building materials are shown in Tables 6.1.1 and
6.1.2. The materials are listed in order of their ability to
decrease the VHP® concentration in the 125-150 ppmv
exposures: carpet, painted structural steel, latex painted
wallboard, ceiling tile, wood, and concrete cinder block.
The order is similar for the 250-300 ppmv test exposures
with the exception of ceiling tile and wood, which are
reversed for these exposures. The values shown are the
average of three replicate exposures. Concrete cinder
block had, by far, the greatest effect of the materials
studied under both concentrations.
Representative concentration profile graphs for each of
the test materials are shown in Figures 6.1.9 through
6.1.14. Each graph consists of two concentration
profiles. The enclosure concentration (gray line) reflects
the hydrogen peroxide concentration within the chamber
during the duration of the test. The concentration of the
enclosure was maintained during the decontamination
phase within either the target or half-target concentration
range. The feed concentration (black line) shows the
hydrogen peroxide concentration exiting the generator.
During the decontamination phase, the generator feed
concentration was adjusted to maintain the chamber
within the target or half-target concentration range.
Figure 6.1.12a shows small dips in the measured
concentration. The cause of the occasional dip was a
small air bubble that was drawn into the vaporizer feed
tube from the hydrogen peroxide solution.
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
Figure 6.1.3: Representative VHP Test Results for Carpet
a) CT of Carpet VHP Exposure at 250-300 ppm (2May05 run)
CT Throughout Run
— CT, Enclosure
—CT, Feed
1500
1250
1000
Ł
a
a.
a.
x
-?se-
-506-
258-
-10123
Time (hour)
b) CT of Carpet VHP Exposure at 125-150 ppm (20May05 run)
CT Throughout Run
CT, Enclosure
—CT, Feed
JS
o.
Q.
o.
I
1500
1250
-weo-
-sm-
4 5
Time (hour)
10
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
Figure 6,1.4: Representative VHP Test Results for Steel
a) CT of Steel VHP Exposure at 250-300 ppm (18May05 run)
CT Throughout Run
CT, Enclosure
—CT, Feed
a.
&
a.
x
1580
125*
-im-
-see-
-10123
Time (hour)
b) CT of Steel VHP Exposure at 125-150 ppm (6Jun05 run)
CT Throughout Run
-CT, Enclosure
—CT, Feed
JE
o.
a.
a.
x
1250
-750-
-250-
345
Time (hour)
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
Figure 6.1.5: Representative VHP Test Results for Painted Gypsum Wallboard
a) CT of Gypsum Wallboard Exposure at 250-300 ppm (6May05 run)
CT Throughout Run
CT. Enclosure '"" CT. Feed
Q.
Q.
Q.
I
>
-1
b)CTof G
Ł
a.
Q
a.
X
>
750 jr
0123456
Time (hour)
/psutn Wallboard VHP Exposure at 1 25-1 50 ppm (31 MayOS run)
CT Throughout Run
- CT, Enclosure — CT, Feed |
250 /r
10123456789
Time (hour)
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
Figure 6,1.6: Representative VHP Test Results for Acoustical Ceiling Tile
a) CT of Acoustical Ceiling Tile VHP Exposure at 250-300 ppm (28Apr05 run)
CT Throughout Run
—CT, Feed
-CT, Enclosure
a.
a.
a.
x
2 3
Time (hour)
b) CT of Acoustical Ceiling Tile VHP Exposure at 125-150 ppm (1 JunOS run)
CT Throughout Run
CT, Enclosure
—CT, Feed
Q.
a.
I
1000
750-
see-
250-
Time (hour)
10
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
Figure 6.1.7: Representative VHP Test Results for Wood
a) CT of Wood VHP Exposure at 250-300 ppm (26Apr05 run)
CT Throughout Run
— CT, Enclosure
—CT, Feed
Q.
Q.
O.
I
1750
1500
1250
1000
500-
Time (hour)
b) CT of Wood VHP Exposure at 125-150 ppm (20May05 run)
CT Throughout Run
— CT, Enclosure
—CT, Feed
Q.
X
1250-
^750-
-500-
-101 2 3 4 5 6 7 8 9 10 11 12 13 14
Time (hour)
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
Figure 6.1.8: Representative VHP Test Results for Concrete Cinder Block
a) CT of Concrete Cinder Block VHP Exposure at 250-300 ppm (4May05 run)
CT Throughout Run
CT, Enclosure
—CT, Feed
a
a
a.
I
25oe-
256-
2000-
17SO
1500
-r25»-
-i«ee-
1234
Time (hour)
b) CT of Concrete Cinder Block VHP Exposure at 125-150 ppm (2Jun05 run)
CT Throughout Run
— CT, Enclosure —CT, Feed
c.
a.
S
O.
X
2000
1750
-two-
1250
3 4
Time {hour}
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
Table 6.1.1 Material Demand Results for Building Materials (125-150 ppmv)
Test
Carpet
Steel
Wallboard
Ceiling Tile
Wood
Concrete
Average
Chamber
Temperature
(°C)
33.0 ±0.7
33.2 ±0.5
33.1 ±0.1
33.1 ±1.1
32. 8 ±0.3
33.5 ±0.2
Average Feed
Concentration
(ppm)
163.4 ±3.2
174.4 ±6.4
197.5 ±2. 6
198.7 ±4. 6
206.1 ±7.1
299.2 ±9.8
Time to reach
target CT
(hr)
7.29 ±0.14
7.36 ±0.13
7.42 ± 0.07
7.51±0.22
7.41 ±0.04
7.43 ± 0.03
DCT
(ppmv-hr)
62.4± 6.0
154. 8 ±31. 3
336.0 ±14.5
363 .2 ±14.5
398.9 ±49.8
1095 .6 ±82.7
MD
(ppmv-hr/hr/m2)
17.83 ±1.40
43. 89 ±9.35
93.33 ±4.06
103.07 ±2.41
110.69 ±13.97
297.58 ±21. 13
J
(g/hr/m2)
0.111 ±0.016
0.274 ± 0.054
0.591 ± 0.024
0.653 ±0.041
0.709 ±0.083
1.870 ±0.123
Table 6.1.2 Material Demand Results for Building Materials (250-300 ppmv)
Test
Carpet
Steel
Wallboard
Ceiling Tile
Wood
Concrete
Average
Chamber
Temperature
(°Q
31.9±0.7
33.1 ±0.6
32.2 ±0.4
33.2 ±0.8
32.3 ± 0.2
32.2 ±0.3
Average Feed
Concentration
(ppm)
344.0 ±5.1
358.1 ±3.3
429.1 ±3.9
436.4 ±3. 8
439.9 ±7.9
594.5 ± 10.2
Time to reach
target CT
(hr)
3. 79 ±0.03
3. 76 ±0.03
3. 73 ±0.01
3. 82 ±0.02
3. 83 ±0.04
3.77 ±0.06
DCT
(ppmv-hr)
87.6±20.8
130.8±21.2
383. 7 ±18.7
451.3 ±7.5
466. 9 ±48.1
1022.9 ±46.1
MD
(ppmv-hr/hr/m2)
48. 15 ±11.34
72.44 ±11. 33
212.03 ±9.86
251.69 ±4.87
250.64 ±23 .28
548.32 ±21.07
J
(g/hr/m2)
0.338 ±0.073
0.455 ±0.050
1.403 ±0.075
1.591 ±0.062
1.650 ±0.162
3.612±0.110
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MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
Figure 6.1.9: Representative Concentration Profile Results for Carpet
a) Concentration Profile for Carpet, VHP Exposure at 250-300 ppm (29Apr05 run)
Vapor Concentration Throughout Run
— Concentration, Enclosure —Concentration, Feed •— —cone, limits
a
a.
c
o
o
a.
0123456
Time (hour)
b) Concentration Profile for of Carpet, VHP Exposure at 125-150 ppm (20May05 run)
Vapor Concentration Throughout Run
Concentration, Enclosure
•Concentration, Feed
— cone, limits
CX
O.
O
o
a.
i
4 5
Time (hour)
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
Figure 6.1.10: Representative Concentration Profile Results for Steel
a) Concentration Profile for Steel, VHP Exposure at 250-300 ppm (ISMayOS run)
Vapor Concentration Throughout Run
-Concentration, Enclosure ^Concentration, Feed
"cone, limits
a
a.
c
o
o
a.
x
588-
88
se
00
\_ „_
-1012345
Time (hour)
b) Concentration Profile for Steel, VHP Exposure at 125-150 ppm (6Jun05 run)
Vapor Concentration Throughout Run
— Concentration, Enclosure —Concentration, Feed —
-cone, limits
a
a
is
o
u
c
o
o
a.
x
3 4
Time (hour)
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
Figure 6,1.11: Representative Concentration Profile Results for Gypsum Wai I board
a) Concentration Profile for Gypsum Wallboard, Exposure at 250-300 ppm (6May05 run)
Vapor Concentration Throughout Run
" Concentration, Enclosure
"Concentration, Feed — —"cone, limits
Time (hour)
b) Concentration Profile for Gypsum Wallboard, VHP Exposure at 125-150 ppm (31 MayOS run)
Vapor Concentration Throughout Run
~ Concentration, Enclosure ^Concentration, Feed — *~~cone, limits
a.
a
c
o
o
a.
x
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
Figure 6.1.12: Representative Concentration Profile Results for Acoustical Ceiling Tile
a) Concenti
a.
a.
c
o
g
C
0)
u
c
o
O
ft.
X
>
b) Concentr
a
a
VHP Concentration
ation Profile for Acoustical Ceiling Tile, VHP Exposure at 250-300 ppm (16Mar05 run)
Vapor Concentration Throughout Run
— Concentration, Enclosure — Concentration, Feed —
•rpftlDV
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
Figure 6,1.13: Representative Concentration Profile Results for Wood
a) Concentration Profile for Wood, VHP Exposure at 250-300 ppm (26Apr05 run)
Vapor Concentration Throughout Run
— Concentration, Enclosure —Concentration, Feed
-cone, limits
Q.
Q.
C
O
u
Q.
Time (hour)
b) Concentration Profile for Wood, VHP Exposure at 125-150 ppm (10May05 run)
Vapor Concentration Throughout Run
"Concentration, Enclosure ^Concentration, Feed
"cone, limits
Q.
a
c
o
o
a.
x
-306-
67
Time (hour)
10
11
12 13
14
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
Figure 6.1,14: Representative Concentration Profile Results for Concrete Cinder Block
a) Concentration Profile for Concrete Cinder Block, VHP Exposure at 250-300 ppm (4May05 run)
Vapor Concentration Throughout Run
Concentration, Enclosure ^Concentration, Feed
~" cone, limits
^ee-
Q.
Q.
o
o
EL
I
-101234567
Time (hour)
b) Concentration Profile for of Concrete Cinder Block, VHP Exposure at 125-150 ppm (2Jun05 run)
Vapor Concentration Throughout Run
— Concentration, Enclosure —Concentration, Feed —
conc. limits
-*ee
a
a.
c
o
c
o
o
a.
x
Time (hour)
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
6.2 Discussion
Carpet and the two materials that were painted (steel and
wallboard) had the lowest VHP® material demand. The
sorptive building materials, such as ceiling tile, wood,
and concrete cinder block had greater VHP® material
demand. Concrete cinder block showed the greatest
material demand of the materials studied.
Using the baseline as the reference point, some of the
materials were observed to adsorb VHP® and others to
decompose VHP®. The aeration time for the 250-ppmv
VHP® run is shown in Figure 6.2. la. Figure 6.2. Ib
shows a zoomed in view of the aeration cycle at the 30-
ppmv end of run with bars highlighting the aeration span
covered by the three replicate runs for each material and
the empty chamber.
The concrete cinder block required the highest increase
in generator output to maintain the target concentration
within the enclosure, hence the highest material demand.
The concrete cinder block also had the shortest aeration
time indicating that the majority of the excess VHP®
introduced into the chamber was decomposed by the
concrete cinder block surface.
The two cellulose-based materials wood and acoustical
ceiling tile required a high increase in the generator
output to maintain the target concentration within the
enclosure. The wood and acoustical ceiling tile tests
also had the longest aeration time indicating that these
materials adsorbed VHP® during the decontamination
phase and off-gassed VHP® during the aeration phase.
The wallboard test results had a similar material demand
value and shorter aeration time compared to ceiling tile
and wood. Based on this comparison, the VHP® was
most likely adsorbed and decomposed by the painted
wallboard surface.
The carpet test results indicated a low material demand
value and an aeration time similar to the baseline study.
Based on this comparison, the VHP® was not adversely
affected by the carpet.
The steel test results indicated a low material demand
value compared to wallboard, ceiling tile, wood and
concrete cinder block. The steel samples also had a
short aeration time comparable to the baseline tests. The
steel may be adsorbing or decomposing the VHP®.
Based on these results, building materials may impact
the ability to maintain the target concentration by
adsorption and/or decomposition of the VHP®. In
addition, some materials may continue to offgas VHP®
after decontamination is completed resulting in longer
cycle times.
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
Figure 6.2.1: Aeration Time for Building Materials Exposed to 250 ppm VHP
a) Aeration Time - Full View Aeration Cycle, 250 ppm Test
— Baseline —Wood -Tile -Steel
— Carpet —Wallboard —30 ppm line —Concrete Cinder Block
0.00
0.50
1.00
1.50 2.00
Time, hours
2.50
3.00
3.50
b) Aeration Time - Zoom View with Approximate Timespan
Aeration Cycle, 250 ppm Test (Zoom View)
— Baseline —Wood —Tile
—Carpet —Wallboard —30 ppm line
Steel
Concrete Cinder Block
0.00
0.50
1.00
1.50 2.00
Time, hours
2.50
3.00
3.50
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MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
6.3 Consequences for Building
Decontamination
This study provides information that may be used to
support the determination of the VHP® concentration
and aeration time requirements for the decontamination
of an interior space containing the building materials
studied. Based on these results, building materials may
impact the ability to maintain the target concentration
by adsorption and/or decomposition of the VHP®. In
addition, some materials may continue to offgas VHP®
after decontamination is completed, resulting in longer
cycle times.
The material demand values reported can be used to
estimate the total hydrogen peroxide capacity required
to maintain the desired peroxide concentration. As an
example of how such an estimate might be generated,
consider two 900 m2 (-10,000 ft2) spaces: one a
warehouse environment and the other an office space.
For this example, the warehouse has a concrete floor,
cinderblock walls, and a steel roof. The office building
has a carpeted floor, painted wallboard walls, and a
dropped ceiling. In both buildings, the walls are 3 meters
from the floor to the ceiling/roof and the building is 30
meters on each side. The buildings will be fumigated at
a concentration of 300 ppmv of hydrogen peroxide for
3.33 hours resulting in a CT of 1000 ppmv-hrs.
Tables 6.3.1 and 6.3.2 give the estimate of required
hydrogen peroxide production capacity by multiplying
the surface area of each material present in the building
by the flux, J, from Table 6.1.2. The requirement
calculated represents the excess capacity that the
hydrogen peroxide generator must supply in addition to
the capacity needed to maintain a concentration of 300
ppmv, or 0.42 g/m3. To illustrate how this information
could be used in practice, consider the STERIS VHP®
100M, which in an open loop configuration has
maximum peroxide and air flow rates of 504 g/hr (24 g/
min of 35% H2O2) and 75 m3/hr, respectively, for a feed
concentration of 6.7 g/m3. Of that capacity, 6.3 g/m3
would be available to overcome the material demand in
the contaminated space. Dividing the material demand
by this excess generation capacity results in the air
exchange rate required to maintain the air concentration
of peroxide and overcome the material demand.
From Tables 6.3.1 and 6.3.2, it is clear that the materials
within a particular building can have a significant impact
on the generation capacity required for decontamination.
The concrete/cinderblock building requires about
twice as much vapor generation capacity as the office
space, mainly due to the high material demand of the
concrete. As a result, the warehouse would require
at a minimum use of eleven STERIS VHP® 100M
units, while the office building would require at least
five. These requirements could be lowered if the air
circulation, temperature and relative humidity within the
buildings were such that the hydrogen peroxide vapor
generators could be configured to output even higher
concentrations.
Table 6.3.1 Material Demand of Warehouse Surfaces
Surface
Concrete floor
Cinderblock walls
Steel ceiling
Total
Surface area
(m2)
929
360
929
J
(g/hr/m2)
3.61
3.61
0.455
HP required
(g/hr)
3354
1300
423
5076
Air exchange
(m3/hr)
532
206
67
805
Table 6.3.2 Material Demand of Office Surfaces
Surface
Carpet
Painted Wallboard
Ceiling tile
Total
Surface area
(m2)
929
360
929
J
(g/hr/m2)
0.338
1.403
1.650
HP required
(g/hr)
314
505
1532
2351
Air Exchange
(m3/hr)
50
80
243
373
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MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
7.0
Quality Assurance Findings
Four technical systems audits were completed. Overall
there were no follow-up corrective actions from testing.
During the first audit two on-the-spot corrections were
made. The first correction occurred during the chamber
shutdown procedure. The operator skipped a step in
the procedure. The auditor caught the mistake and the
operator backed up and completed the shutdown. The
second mistake was misnumbering of one coupon. The
operator identified the error, re-measured the coupon
and matched the coupon to the correct CoC card. The
sample was re-numbered. The corrections during the
first audit were not unexpected since the procedures and
equipment were new and the audit was done during the
first test.
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MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
8.0
Challenges and Lessons Learned
8.1 VHP® Relative Humidity Sensors
The Vaisala HUMICAP humidity sensor (model
HMT333) read slightly high in the presence of VHP®
at approximately 300 ppmv, but when removed from
air containing VHP® the sensors responded normally
with no change in response. The relative response of
the sensor to VHP® and humidified air was checked by
separately injecting distilled water or 35% hydrogen
peroxide at identical rates into the VHP® generator
and observing the resultant %RH in the chamber after
equilibration. The injection rate was similar to that used
during most of the exposure runs. When distilled water
or 35% hydrogen peroxide was injected, the sensor
read 32.2 %RH and 34.3 %RH, respectively, indicating
that the sensor reads the %RR high by approximately 2
%RH units in the presence of VHP®. Even though the
VHP® effect on %RH was small, VHP® did not have
any impact on the maximum 30% RH SOR requirement
since the sensor was not exposed to VHP® at the SOR.
The %RH probe response was verified after completing
approximately 3/4 of the runs by exposure to humidified
air above saturated salt slurries. Slurries of potassium
acetate, potassium carbonate and sodium chloride were
used to yield standard humidities of 23, 44, and 76 %
relative humidity, respectively. The variations between
the standard % relative humidities and the sensor %RH
readings (23.4, 42.6, and 77.9 %RH, respectively)
were < 3.5%. During the test runs the %RH generally
mimicked the VHP® concentration in the enclosure,
showing that the change in %RH was related generally
to the changes in VHP® concentration (Figure 8.1).
Figure 8.1: Comparison of VHP Concentration and %RH
a) Aeration Time - Full View
Concentration, Enclosure —% RH
10
34567
Time (hour)
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MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
8.2 Calibration of Drager Hydrogen
Peroxide Electrochemical Sensors
Initial calibration attempts for the hydrogen peroxide
sensors using sulfur dioxide in nitrogen gas revealed that
the sensors were highly sensitive to changes in pressure.
The calibration procedure with sulfur dioxide required
that the sensors be removed from their test enclosures
and placed in a low volume calibration adaptor through
which the calibration gas could be passed. This
procedure allowed for conservation of the calibration
gas and also for the quick equilibration of the calibration
gas concentration. The calibration procedure was quick
and straightforward, but when the sensors were placed in
their test enclosures, the inlet sensor read higher than the
enclosure sensor, due to the inlet enclosure experiencing
slightly more pressure than the exit enclosure.
Switching the sensors revealed that the variation was
due to their placement and not the specific sensor. The
sensors could be calibrated with the sulfur dioxide
gas procedure, but the verification agreement with the
peroxide concentration from the iodometric titration was
typically in error by approximately 15% due to the slight
variation in enclosure pressures. Attempts to refine the
sulfur dioxide calibration procedure and successfully
validate were exhausted.
The hydrogen peroxide sensors were recalibrated in
place using VHP® concentration values determined by
chemical titration of VHP® captured in bubbler solutions.
The inlet hydrogen peroxide detector was calibrated
to measure from 0 to 800 ppmv H2O2, and the outlet
hydrogen peroxide detector was calibrated to measure
from 0 to 340 ppmv H2O2IAWIOP DS04001. The
outlet sensor was expected to experience concentrations
no greater than 300 ppmv and was therefore calibrated
slightly higher at 340 ppmv. The inlet sensor was
calibrated from 0 to 800 ppmv H2O2 to accommodate
anticipated higher VHP® concentrations in the feed
air. Verification of both sensors was conducted during
each run using the average value from three iodometric
titrations on the VHP® stream entering and exiting the
glove box (IOP DS04019).
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MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
9.0
References
(1) Jahnke, M. and Lauth, G., "Biodecontamination
of a Large Volume Filling Room with Hydrogen
Peroxide," Pharm. Eng. 1997, 2-12.
(2) McDonnell, G. G.; Gringol, G.; Antloga,
K. "Vapour-Phase Hydrogen Peroxide
Decontamination of Food Contact Surfaces," Dairy
Food Environ. Sanit. 2002, 868-873.
(3) Brickhouse, M. D.; Turetsky, A.; McVey, I.
"Decontamination of CBW Agents by mVHP:
Demonstration of the CBW Decontamination of
a Building using mVHP," Edgewood Chemical
Biological Center, 2005.
(4) Brickhouse, M. D.; Turetsky, A.; Maclver, B.;
Pfarr, I; Dutt, D.; McVey, I.; Alter, W.; Lloyd,
J. P.; Mark A. Fonti, J. "Vaporous Hydrogen
Peroxide Decontamination of a C-141B Starlifter
Aircraft: Validation of VHP and mVHP Fumigation
Decontamination Process Via VHP-Sensor,
Biological Indicator, and HD Simulant in a
Large-Scale Environment," Edgewood Chemical
Biological Center, 2005.
(5) "EPA Guidance on Environmental Data Verification
and Data Validation, EPA QA/G-8," U.S.
Environmental Protection Agency, 2002.
(6) Wagner, G. W; Sorrick, D. C; Procell, L. R.; Hess,
Z. A.; Brickhouse, M. D.; McVey, I. K; Schwartz, L.
I. In CB Defense: Timonium, 2003.
(7) Brickhouse, M. D. "Quality Assurance Project
Plan and Work Plan for Effects of Vaporized
Decontamination Systems on Selected Building
Interior Materials, Doc. No. DSQAPP2004MC,"
2004.
(8) "Quality Management Plan (QMP) for the National
Homeland Security Research Center (NHSRC)
Office of Research and Development (ORD)," U.S.
Environmental Protection Agency (U.S. EPA), 2003.
(9) "Quality Management Plan for Environmental
Programs," Edgewood Chemical Biological Center
Research, Development and Engineering Command,
2003.
(10) "EPA Guidance for Data Quality Assessment,
Practical Methods for Data Analysis, EPA QA/G-9,"
U.S. Environmental Protection Agency, 2000.
(11) "EPA Requirements for Quality Assurance
Project Plans, EPAQA/R-5," U.S. Environmental
Protection Agency, 2001.
(12) "EPA Guidance for Quality Assurance Project Plans.
EPAQA/G-5," U.S. Environmental Protection
Agency, 2002.
13) Lalain, T. "Effects Of Vaporized Hydrogen Peroxide
On Selected Building Interior Materials," ECBC
Technical Report, In Progress.
(14)Procell, L. "Material Exposure to Vaporized
Hydrogen Peroxide, RNG-107," 2005.
(15)Procell, L. "Procedure forthe Operation of the
Hydrogen Peroxide Glove Box and Exposure of
Materials, DS04015," 2005.
(16) Lalain, T. "Placement of Coupons in Chambers for
Deposition Velocity / Material Compatibility Testing
forthe EPA Program, DS04016," 2005.
(17)Brickhouse, M. D. "Quality Assurance Project Plan
and Work Plan for Deposition Velocity Studies:
Materials Sorption of Vaporized Hydrogen Peroxide
or Chlorine Dioxide, Doc. No. DSQAPP2004DV,"
2004.
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MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
-------
MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
Appendix A:
Detailed Coupon Preparation and Inspection Procedures
Appendix A: Detailed Coupon Preparation and Inspection Procedures
COUPON PREPARATION PROCEDURE
The coupon preparation, unless otherwise noted, will be conducted at the Edgewood Chemical
Biological Center Experimental Fabrication Shop.
Mechanically Graded Lumber (Bare Wood)
- The machined ends of the stock will be discarded by removing > % in. of the
machined end. Coupons will be cut from stock using a table saw equipped with
an 80 tooth crosscut blade.
Latex-Painted G VPS urn Wai I board
• Stock Item Description: 1/4 in. 4 ft. x 8 ft. Drywall
• Supplier/Source: Home Depot, Edgewood Maryland
• Coupon Dimensions: 6 in. x6 in. x 1/4 in.
• Preparation of Coupon:
- The ASTM method requires that the samples be taken from the interior of material
rather than from the edge (machined edge). The machined ends of the stock will
be discarded by cutting away > 4 inches from each side.
Coupons will be cut from stock using a table saw equipped with an 80 tooth
crosscut blade.
- The 6 in. x 6 in. coupons will be painted with 1-mil of Glidden PVA Primer and
followed by 1-2-mils of Glidden latex topcoat. The primed coupons will be allowed
to stand for > 24 hours prior to the application of the topcoat.
- All six sides of the 6 in. x 6 in. coupon will be painted.
Concrete Cinder Block
Stock Item Description: 8 in. x 16 in. x 1.5 in. concrete block cap
Supplier/Source: York Supply, Aberdeen Maryland
Original Coupon Dimensions: 4 in. x 8 in. x 1.5 in.
Modified Coupon Dimensions: 4 in. x 8 in. x 0.5 in.
Preparation of Coupon:
Coupons will be cut from stock using a water-jet.
Four coupons will be cut from each stock piece.
Original dimensions too large for material testing
o Each coupon cut into three sections.
o Two sections measured at modified coupon dimensions
o Third section discarded
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MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
Appendix A:
Detailed Coupon Preparation and Inspection Procedures
Stock Item Description: 12 ft. Powerhouse 20 Tradewind
Supplier/Source: Home Depot, Edgewood, Maryland
Coupon Dimensions: 6 in. x 8 in.
Preparation of Coupon:
Coupons will be cut from the stock using a utility knife.
- The longer direction (8 in.) will be cut parallel to the machine edge.
- The machined edge will be discarded by removing > 1/4 in.
Painted Structural Steel
• Stock Item Description: A572 Grade 50, 4 ft. x 8 ft. x % in.
• Supplier/Source: Specialized Metals
• Coupon Dimensions: 1/4 inches x 12 inches total, dog bone shaped with 2 inches
wide at ends, %" wide inch center
• Preparation of Coupon:
Coupons will be cut from stock using a water-jet.
- A visual observation will be conducted on each coupon to determine if size and
shape have deviated from dimension. If deviation has occurred, the coupon will
be discarded.
Coupons will be cleaned and degreased following procedures outlined in TTC-
490.
Coupons will be prepared for painting per TT-P-645 with red oxide primer.
The Edgewood Chemical Biological Center Experimental Fabrication Shop prepared
the materials lAWthe standards used for the preparation and painting of steel. TTC-
490 is a Federal Standard providing cleaning methods and pretreatment for iron
surfaces for application of organic coatings. The pretreatment is the application of a
zinc phosphate corrosion inhibitor. TT-P-645 is a Federal Standard for the application
of alkyd paint. These standards were not obtained through this program but were
purchased by the Shop for their work.
Ceiling Suspension Tile
• Stock Item Description: Armstrong 954, Classic Fine Textured, 24 in.x 24 in.x 9/16 in.
• Supplier/Source: Home Depot, Edgewood, Maryland
• Coupon Dimensions: 12 in. x 3 in. x 9/16 in.
• Preparation of Coupon:
Coupons will be cut from stock using a table saw equipped with an 80-tooth
crosscut blade.
Sixteen samples will be removed from each stock item.
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MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
Appendix A:
Detailed Coupon Preparation and Inspection Procedures
COUPON INSPECTION PROCEDURE
All coupons will be inspected prior to testing to ensure that the material being used is in suitable
condition. Coupons will be rejected if there are cracks, breaks, dents or defects beyond what
are typical for the type of material. In addition, coupons will be measured to verify the coupon
dimensions. Coupons deviating from the dimension ranges listed below will be discarded.
Mechanically Graded Lumber (Bare Wood) 10 in. ± 1/16 in. x 1.5 in. ± 1/16 in. x 0.5 in. ±
1/32 in.
Latex-Painted Gypsum Wallboard
6 in. ± 1/16 in. x6 in. ± 1/16 in. x 0.5 in. ± 1/16
in.
Concrete cinder Block
Carpet
Painted Structural Steel
Ceiling Suspension Tile
4 in. ± 1/4 in. x 8 in. ± 1/4 in. x 0.5 in. ± 1/8 in.
6 in. ± 1/8 in. x8 in. ± 1/8 in.
1/4 in. ± 1/128 in. x 12 in. ± 1/16 in. with 2 in. ±
1/16 in. wide at ends, % in. ± 1/16 in. wide inch
center
Lot SS: same but with 0.27 in. ± 0.02 in.
thickness
12 in. ± 1/8 in. x 3 in. ± 1/16 in. x 9/16 in. ±
1/16 in.
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MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
Appendix B:
Coupon IndentifierCode
Appendix B: Coupon Identifier Code
All coupons will be marked with an ID number that will consist of a nine character
alphanumeric code. A description of the identifier pattern and an example code are shown
below.
Code Pattern
Character
1
Explanation
Material
W
G
S
T
C
R
B
=
=
=
=
=
= acoustic ceiling tile
= concrete cinder block
= carpet
= circuit breakers
3
4,5
6,7
Fumigant:
V = VHP
N = no fumigant
Test start date
year for example: 4 = 2004
month for example: 06 = June
day for example: 10 = the 10th of a month
8,9
Chamber position (see IOP DS04016 figure 1)
Example
GV4101104
Gypsum Wallboard with test start date of October 11th, 2004.
Chamber position number 4.
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MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
Appendix B:
Coupon Indentifier Code (Cont.)
IOf* DS4J4Q1B ftattrm t, "Coupon f*tacarnant
I ,1
r—ta&-
i— T1W
d> Steel
jL-ti. ^Jd-iSlb jat
*} WMMmon]
-iSa,^. al&cstofc'i^flaDjJtl
coupon
on racJt sti^ws fnam
fee leriBBh acid wtttti 1v
of gtave t»aj( transfer cKarr»tier
2 *
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MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE
-------
United States
Environmental Protection
Agency
PRESORTED STANDARD
POSTAGES FEES PAID
EPA
PERMIT NO. G-35
Office of Research and Development (8101R)
Washington, DC 20460
Official Business
Penalty for Private Use
$300
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