www. epa. gov/researc h
technical BRIEF
INNOVATIVE RESEARCH FOR A SUSTAINABLE FUTURE
Decontamination Options for Restoring Subway Systems
following a Bacillus anthracis Contamination Incident
PURPOSE
This technical brief provides deci sion makers with practical information on decontamination methods
that could be deployed during the remediation of rolling stock (railcars) and physical structures (tunnels
and stations) of an underground transit system following a biological contamination incident.
INTRODUCTION
Following a biological incident in a transportation hub such as a subway system, effective remediation
of railcars, subway tunnels, and stations would require the use of various approaches to characterize,
clean-up, and clear the contaminated area for reentry and reuse. The U.S. Department of Homeland
Security initiated the Underground Transport Restoration (UTR) Project in 2013 to improve the
capability of transit systems to recover rapidly from a biological contamination incident. As part of this
UTR Project, the U.S. Environmental Protection Agency (EPA) evaluated multiple methodologies for
decontaminating subway system and rolling stock materials contaminated with spores of Bacillus
anthracis (Ba) Ames, the causative agent for anthrax, and/or a Ba surrogate. Several volumetric
(fogging and fumigating) [1] and surface [2] decontamination methods have formerly been evaluated for
the inactivation of biological agent contamination and operational use; however, the UTR project
selected decontaminants and test parameters specifically to assess operational use, representative
materials, and conditions typical of more challenging subway system environments (e.g., impact on
decontamination efficacy in presence of grimed or dirty surfaces).
This technical brief reviews the bench-, pilot-, and field-scale decontamination research that was
conducted by EPA under the UTR project. It summarizes the findings that are most applicable for
operational use in the following remediation areas:
•	decontamination methods for railcar and related materials
•	decontamination methods for subway tunnels and stations
DECONTAMINATION METHODS FOR RAILCAR AND RELATED MATERIALS
Fogging sporicidal liquids and fumigation with methyl bromide (MB) were tested to assess
decontamination efficacy on railcar contents and related material, including material that contained dirt
and grime. The findings, applicable to material decontamination in the field, from two UTR project
studies are described below.
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Decontamination of Subway Railcar and Related Materials via the Fogging of Peracetic
Acid and Aqueous Hydrogen Peroxide
Type of Research, Reference Number: Pilot-Scale Research Stud}
Research Description: Decontamination efficacy of two sporicidal
liquids, peracetic acid [PAA | at a 4.5% concentration and hydrogen
peroxide [H2O2] at three concentrations (8, 22, and 35%), was
assessed at different temperatures (10 and 20 degrees Celsius [°C])
using two types of fogging equipment on samples of several railcar
materials. Many of the materials used in the study originated from
actual in-use subway railcars, and included carpet, aluminum seat
backs, seat upholstery, rubber flooring, Mylar® coating (from a
glass window), fiberglass interior siding, railcar axle grease, and a
used cabin air filter. Additionally, a new cabin air filter, new carpet,
unpainted concrete (common subway tunnel material) and new
grease in two configurations (spores dried on top of the grease and
dried spores mixed [embedded] into the grease) were included in
the study. The two fogger technologies (Sani-Tizer™ fogger
[Curtis Dyna-Fog Ltd., Jackson, GA] and Mini Dry Fog System
[Mar Cor Purification, Plymouth, MSJJ (Figure 1) were tested for
their ability to disseminate fogged sporicidal liquids throughout the
large test chamber. Flow rate, droplet size, and operational settings
for these foggers are detailed in the report [3 J.
Findings:
•	Efficacious1 conditions (at least one test producing > 6 log reduction [LR]) were achieved for every
material except unpainted concrete, new grease (with spores embedded), and carpet.
•	The type of tested fogger did not have a significant effect on LR.
•	Fog was well-distributed and decontamination efficacy did not vary significantly by location within
the test chamber.
•	Efficacy was diminished somewhat at lower temperatures.
•	The 35% H2O2 fog produced similar results as PAA fog; the 22% H2O2 was somewhat less effective.
, [3]
Figure 1. Sani-Tizer Fogger (A) and
Mini Dry Fog System (B).
1 A decontaminant product is considered to be an effective sporicide or sporicidal decontaminant if a 6 log reduction (LR) or
greater is achieved in appropriate laboratory testing [4],
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Decontamination of Subway Railcar via Methyl Bromide Fumigation
Type of Research, Reference Number: Field-Scale Research Study, [5]
Research Description: Operational aspects and the efficacy of MB fumigation were evaluated for
inactivating surrogate Ba spores on a 1980s-era subway railcar (Figure 2) located at Sandia National
Laboratories' campus in Livermore, California.
70' Long, 10' Wide, and 13' High
Including Trailer Below Rail Car
Figure 2. Schematic diagram of subway railcar, with dimensions in feet.
The fumigation test parameters were 212 milligrams per liter (mg/L) MB (with no chloropicrin, an
irritant typically added to MB to aid in the detection of release) at 24 °C and the relative humidity (RH)
greater than 75%, maintained for 36 hours. Four fans (operating at 3,000 cubic feet per minute each [85
nvVmin]). ten 1,500-Watt radiant heaters, and four humidifiers were strategically placed inside the
subway railcar to ensure uniform MB concentration, temperature, and RFT conditions throughout the
railcar. Ba surrogate contaminated coupons (excised samples of test materials) were also placed inside
the fumigation envelope and were extracted at 6, 12, 18, 24, and 30 hours after the start of fumigation to
determine the contact time dependence in efficacy.
The railcar was tented with a 6-
millimeter-thick, high-diffusion-
resistant polyethylene vinyl alcohol
tarpaulin (tarp) (two tarps were joined
together as described in the report [5]).
High-density polyethylene (FLDPE)
tubing was draped over the top and
sides of the railcar, at multiple
locations, to provide air space between
the railcar and the tarp. The skirt of
the tarp was weighed down with
sandbag "snakes" and the timed-series
test coupon holder (polyvinyl chloride
[PVC]-pipe constmction) was sealed
.	Figure 3. Tented railcar with termini of PVC piping used for timed-
at its exterior terminus with a
, ,	series coupon extractions,
threaded PVC cap (Figure 3).
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Two coupons of each railcar material (nylon loop-pile carpet, fiberglass wall paneling, aluminum,
rubber flooring, Mylar® on polycarbonate, and vinyl seating) were placed at 20 locations inside (40 total
for each material) and outside the railcar, including behind closed panels and confined spaces within
mechanical and electrical equipment. An activated carbon scrubber system was used to capture the MB
after the fumigation. The system consisted of two 900 pounds (408 kilograms) vessels of activated
carbon, a blower, flexible ducting, a vent stack, and fittings. At the conclusion of the 36-hour fumigation
period, the railcar was aerated, and the coupons were collected and sent to a laboratory for analysis.
Findings:
•	No viable spores were recovered from the fiberglass and aluminum test coupons after
fumigation.
•	Out of the 40 coupons for each material, two nylon carpet coupons, one rubber flooring coupon,
one Mylar® coupon, and eight vinyl seating coupons tested positive for viable spores after
fumigation.
•	Analysis of the time-series coupons exposed for 30 hours showed that viable spores (10 colony-
forming units [CFU]) were recovered from only one (fiberglass coupon) of the twelve coupons,
resulting in an average recovery of 5 CFUs for fiberglass and zero recovered viable spores for all
other materials. LRs for the quantitative temporal assessment portion at 30 hours after exposure
were greater than or equal to 6 LR for all coupons except for the fiberglass coupon, which had an
LR value of 5.5.
•	At the 24-hour exposure time, efficacy was greater than or equal to 2.5 LR for all coupons, with
all material types having recoverable spores.
•	The activated carbon scrubber was effectively deployed and used to reduce the MB
concentration inside the tented volume from approximately 55,000 parts per million (ppm) to
less than 20 ppm within 5 hours following the completion of fumigation activities.
Based on several positive test coupon results from this study, it is suggested that the fumigation of a
railcar for Ba be extended from 36 to 48 hours and that the temperature, RH, and MB concentration be
maintained above the set points of 24 °C, 75% RH, and 212 mg/L, respectively, during the 48-hour
fumigation period. In addition, based on the result of eight positive results for the vinyl seat covering
coupons, it is suggested that railcar seating material be removed or sprayed down with pH-adjusted
bleach before fumigation to aid in the inactivation of Ba spores.
DECONTAMINATION METHODS FOR SUBWAY TUNNELS AND STATIONS
Several decontamination technologies were tested to access decontamination efficacy on subway system
building materials and contents. Fumigation technologies using chlorine dioxide (CIO2) and MB were
evaluated in bench-scale studies. Fogging and spraying technologies were evaluated via field-scale tests
in a mock subway system located at Fort A. P. Hill in Bowling Green, Virginia. Additionally,
commercially-available equipment was evaluated for the spraying of sporicidal liquids on subway tunnel
materials and was operationally demonstrated (with water) in the Fort A. P. Hill mock subway system.
The findings, applicable to subway infrastructure decontamination in the field, from four UTR Project
studies are described below.
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Decontamination of Subway Building Materials via Chlorine Dioxide Fumigation
Type of Research, Reference Number: Bench-Scale Research Study, [6]
Research Description: The study evaluated decontamination efficacy of CIO2 on grimed subway
building materials (concrete, painted steel, and ceramic tile) with various fumigation conditions. The
impact of CIO2 concentration, lower temperatures (11 °C), RH (75%), and presence of dirt and grime
were assessed. The CIO2 was generated by a ClorDiSys-GMP (ClorDiSys, Inc., Lebanon, NJ) system.
The system configuration used for the test can be found in the report [6],
Findings:
•	Fumigation conditions (temperature, RH, CIO2 concentration, and fumigation time) all have a
marked effect on the efficacy of the CIO2 fumigant. Substantially lower efficacies were observed at
11 °C compared to 24 °C (see Figure 4).
•	Furthermore, a 6 LR in viable spores can be obtained for the subway infrastructure materials by
CIO2 fumigation if the temperature is at or above 24 °C combined with RH greater than 75%. These
conditions occur both for 12 hours (h) fumigation at 230 parts per million volume (ppmv) CIO2 or 4
h at 3500 ppmv CIO2.
CI02 Fumigation Efficacy at 200 ppmv CI02 and 75% RH
24 C - 12h
11°C-12h
Grimed Concrete Washed Concrete Grimed Painted Washed Painted Grimed Tile Washed Tile
Steel
Steel
Figure 4. Summary of log reductions results for CIO2 fumigation at 200 ppmv on three types of
subway building material. Note: Non-grimed ("washed") painted steel and washed tile were not
included in test at 11°C /24 hours.
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•	No tests achieved 6 LR in viable spores at cold temperatures in a subway environment (11-13 °C
and 70-80% RH) for periods of fumigation that are otherwise efficacious at 24 °C and 75% RH.
Extending the fumigation time at this low temperature to 24 h at approximately 200 ppmv CIO2 or 9
h at 3300 ppmv CIO2 did not improve efficacy.
•	Further research is recommended to identify whether efficacious CIO2 fumigation conditions could
occur at low temperatures under other conditions, e.g., a pre-wetting of building surfaces prior to
fumigation
•	Impact of dirt and grime on decontamination efficacy was less noticeable than that of temperature
and was dependent on the material.
Decontamination of Subway Building Materials via Methyl Bromide Fumigation
Type of Research, Reference Number: Bench-Scale Research Study, [7]
Research Description: The decontamination efficacy of
MB was assessed on four types of common subway
building materials (ceramic tile, painted carbon steel,
weathered concrete, and granite) with and without
simulated subway grime application as shown in Figure 5.
Ten tests were conducted at a target concentration of 212
mg/L MB, target temperatures of 4.5 or 10 °C, target RH
of 50% or 75%, and contact times ranging from 2 to 9 days
to assess the effect of these operational parameters on
decontamination efficacy.
Findings:
•	Fumigation conditions (temperature, RH, and
fumigation time) affected the efficacy of the MB
fumigant.
•	The presence of grime increased the time required to
achieve 6 LR. The time require to achieve >6 LR at
212 mg/L MB concentration and 10°C was four days for non-grimed material and five days for
grimed materials (Table 1).
Without Grime Application
With Grime Application
Figure 5. Coupons without (top) and with
(bottom) grime application. From left to right:
ceramic tile, painted carbon steel, weathered
concrete, and granite.
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•	No tests resulted in >6 LR of B.a. Table 1. Time Required for >6 Log Reduction for Bacillus
Ames on all materials when	anthracis (B.a.) on All Materials
fumigating at 50% RH. More
specifically, increasing MB
concentration, temperature, or
contact time at 50% RH did not
improve decontamination efficacy.
In contrast, when fumigating at
75% RH, increasing the
temperature and contact time
improved efficacy.
•	No impacts to subway building
materials were observed. Only chloropicrin [not included in this test] would have resulted in
corrosion, not the MB itself.
Operational Decontamination Using Fogging and Spraying Techniques in a Mock
Subway System
Type of Research, Reference Number: Field-Scale Research Study, [8]
Research Description: This operational field test focused on obtaining sampling, decontamination,
waste management, cost analysis, and operational information for the remediation of a subway system
after contamination with a Ba surrogate. Testing consisted of two separate rounds for decontamination
of the mock subway system including two simulated news- and food stands (Figure 6). Both rounds
included a decontamination efficacy assessment, composite sampling, a grimed and non-grimed material
coupon study, a waste management assessment, and an overall cost analysis of the approaches. Plastic
barriers in both stairways and across the track-exit section were installed to contain the study area and
reduce the spread of contamination.
MB Concentration
(mg/L)
Grimed
Temperature
(° c)

Time (days)
Required to
Achieve >6 LR on
All Materials
212
No
10
75
4
212
Yes
10
75
5
212
Yes
4.5
75
7
Stairs
Stairs
Barrier
Platform
Zone 2
Zone 3
Volume = 160.000 ft3
Length = 275 ft
length 370 ft
End of Tunnel
Figure 6. Schematic of mock subway tunnel and station located at Fort A. P. Hill.
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Figure 7. Six-person team in level A personal
protective equipment spraying pAB on celling,
side walls, and ballast of tunnel.
During Round 1, four L-30 foggers (Curtis Dyna-Fog,
Ltd., Westfield, IN) were used to produce a fog from a
diluted bleach solution (1-part bleach to 3 parts water).
During Round 2, subway surfaces were sprayed with a pH
amended bleach (pAB) solution (1-part bleach, 1-part
white vinegar, and 8-parts water) using a skid sprayer
(Northstar Model 268170, Northern Tool and Equipment,
Burnsville, MN) with a 200-gal. [757 liters] tank (Figure
7). The sprayer was modified to allow the use of four
hoses equipped with spray nozzles.
Dissemination of the surrogate organism (Bg) was
performed using an aerosol generator, so the
contamination was approximately uniform with regards to
CFUs (viable spores) per square foot (ft2) of sample area
across the study area.
Samples were collected pre- and post-decontamination for
comparison of recovery and assessment of
decontamination efficacy in the tunnel and platform areas
as well as in difficult-to-reach areas such as the railroad ballast, news and food stand kiosks.
Findings:
• In both rounds, a minimal number of spores were detected post-decontamination ("decon").
W Round 1 (fogging with diluted bleach):
•	Average surface concentration of surrogate (determined from pre-decon samples) was
1.3	x 10' 5.4 105 CFU/ft2
•	Temperature was -24° C and RH measurements
ranged from ~ 60 to 100%, the latter value
occurring during fogging, as expected.
•	~ 370 gal. [1434 liters] of bleach solution was
fogged over 13 hours.
•	Eleven out of a total of 132 post-decon samples
were positive. Of these, seven were kiosk-associated Figure 8. Round 1 sampling results,
surfaces and materials (miscellaneous items
including T-shirts, wax paper, hot dog bun, wooden stand, plexiglass poster) (Figure 8).
•	All grimed and non-grimed coupons were zero except for one painted steel coupon (3 CFU).
> Round 2 (spraying pH amended bleach):
•	Average surface concentration of the surrogate (determined from pre-decon samples) was
5.4	H 10 ' 5.0 - 104 CFU/ft2
Sampling Results Post Fogging
7	4_
Non-detects
Detects-Kiosk
Detects-Other
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•	Equipment used to monitor temperature and RH
was destroyed during pAB spraying—no data
were recorded.
•	575 gal. pAB solution was applied (-42 hours of
manpower in Level A personal protective
equipment).
•	Five out of a total of 138 post-decon samples
were positive for contamination. Of these, four
were kiosk-associated surfaces and materials
(cash, hot dog, T-shirt, and newspaper) (Figure 9).
•	All grimed and non-grimed coupons produced zero CFUs except for one ceramic tile coupon
(3 CFU).
There was no practical difference observed in the decon efficacy between the two decontamination
rounds (fogging with diluted bleach vs. spraying with pH amended bleach).
There were no adverse impacts to the Fort A. P. Hill facility; only a slight additional oxidation was
observed on the subway rail track.
Removal of porous materials for ex situ waste treatment was a more consistently effective approach
for ensuring that waste materials do not contain residual spores.
Overall, the remediation cost of this operational demonstration was largely driven by sampling and
analysis, both in terms of labor costs associated with laboratory analysis as well as the significant
contribution of personal protective equipment from the sampling teams to the overall waste streams
(Figure 10).
Overall Remediation Cost
$450,000
$400,000
$350,000
$300,000
$250,000
$200,000
$150,000
$100,000
$50,000
$-
Round 1 - Fogging	Round 2 - Spraying
¦ IC Cost ¦ Sampling and Analysis Cost ¦ Decon Cost ¦ Waste Management Cost
Figure 10. Breakdown of overall remediation costs.
Sampling Results Post pAB Spraying
4__ 1
Non-detects
Detects-Kiosk
Detects-Other
Figure 9. Round 2 sampling results.
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A direct extrapolation of these cost elements to an actual large-scale or wide-area incident should be
done with caution considering the research nature of this field study. For example, the implementation
of a different sampling strategy that covers a multi-station incident may lead to a different IC and
sampling and analysis cost contribution to the overall remediation cost. The cost of the demonstrated
decontamination approaches was comparable within this study based on a high upfront cost for
equipment for Round 1 (fogging) and a high labor cost for execution of Round 2 (spraying).
Extrapolation to multiple stations and large sections of track in between stations will magnify the cost
difference for decontamination and waste management.
Evaluation of Commercially-Available Equipment for the Decontamination of a
Subway System
Type of Research, Reference Number: Bench-, Pilot-, and Field-Scale Research Studies and
Demonstration, [9]
Research Description: Commercially-available
equipment capable of rapidly spraying sporicidal liquids in
a subway system was identified and ranked according to
three metrics: commercial readiness/availability, ease of
deployment, and decontamination application rate. Based
on these criteria, three equipment types were selected for
bench-scale durability testing to determine material
compatibility of each equipment's wetted components.
Two of the three technologies (Figure 11) were selected for
a field-scale demonstration at the Fort A. P. Hill mock subway system in which water was sprayed onto
the platform and tunnel. The two demonstrated technologies included: (1) an orchard sprayer (Air-O-Fan
Products Corporation, Reedley CA) and (2) a dust suppression technology (DustBoss DB30, Dust
Control Technology, Peoria, IL). Additionally, the Air-O-Fan sprayer was selected to perform pilot-
scale decontamination efficacy tests to operationally evaluate sprayed pAB against a Ba surrogate in an
ambient breeze tunnel testing facility. Testing was conducted at target delivery speeds of 1.2 and 2.4
mph, target temperature of 10 °C, uncontrolled RH ranging from 59 to 98 percent (%), vertical and
horizontal coupon orientations, and contact times ranging from 30 minutes (min) to 12 hours (overnight)
for a total of 4 tests.
Findings:
Compatibility Tests with pAB
• Nozzle and pump diaphragm failures were observed. Most failures appear to be preventable
by altering part materials (i.e., use stainless nozzles rather than brass).
Figure 11. Orchard sprayer (A) Dust
suppressor (B).
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•	Ambient Breeze Tunnel Decontamination Tests
with p.AB
•	Achieved high efficacy (>6LR) on tile
(horizontal and vertical).
Concrete was more difficult to
decontaminate.
•	Repeated applications on concrete increased
efficacy.
1	application - ~1 LR
2	applications - ~3 LR
3	applications - ~4 LR
Figure 12. Air-O-Fan operating on railcar at the
•	Demonstration at Mock Subway System (Figure mock subway system (spraying water in
12)	demonstration).
The commercial equipment sprayed the mock subway system 400 times faster than fogging
or manual spraying.
CONCLUSIONS
Several candidate technologies were evaluated under the UTR project for operational use and
inactivation of Ba surrogate spores under conditions representative of a subway system environment.
During a response to a biological incident, users of this document might need to extrapolate
experimental findings from the bench-scale studies to the field, then field-prove and modify the
decontamination techniques as necessary to help establish the process-knowledge required for the
subway environmental- and site-specific conditions.
For decontamination of railcar materials, volumetric decontamination options were evaluated including
fogging with sporicidal liquids (PAA and H2O2) and fumigating with MB. The results of the pilot-scale
fogging study showed that the fog produced from a 35% aqueous H2O2 solution had similar results as
the 4.5% PAA fog and that a 6 LR was possible for most of the tested materials, however efficacy
diminished somewhat at lower temperatures. The field-scale fumigation of a railcar with MB resulted in
several positive samples, therefore it is suggested to extend the fumigation to 48 hours. Additionally, the
temperature, RH, and MB concentration should be maintained above the set points of 24 °C, 75% RH,
and 212 mg/L, respectively, during the 48-hour fumigation period. Both studies indicated that effective
decontamination of railcar material may require surface treatment or removal of porous items such as
carpet and upholstery prior to volumetric decontamination of the railcar.
For decontamination of subway system infrastructure and contents found within the station and tunnel,
several decontamination options were evaluated. General findings from the bench-scale fumigation
studies conducted on building materials with CIO2 and MB include (1) increasing temperature, RH, and
contact time (and concentration for CIO2) will improve efficacy, and (2) the presence of grime may
require increased fumigation times or another decontamination approach such as surface treatment. CIO2
fumigation at 12 h at 230 ppmv or 4 h at 3500 ppmv showed a 6 LR at temperatures at or above 24 °C
combined with RH greater than 75%. For MB, the time required to achieve a >6 LR at 212 mg/L
concentration, 10°C, and 75% RH was four days for non-grimed material and five days for grimed
materials.
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The decontamination field tests conducted at the Fort A. P. Hill mock subway system resulted in a
minimal number of positive samples post-decon for both decontamination technologies (fogging with
diluted bleach and spraying with pH amended bleach). Most of the positive samples were from kiosk
items that would be considered waste and it was determined that removal of these porous materials for
ex situ waste treatment is a more consistently effective approach for ensuring that waste materials do not
contain residual spores. Additionally, there were no major adverse impacts to the Fort A. P. Hill facility
caused by either decontamination approaches.
The commercially-available equipment tested and demonstrated may be an effective option for
deployment of sporicidal liquid after a release of B.a. spores in a subway environment assuming some of
the sprayer components can be replaced with more rugged materials. While the pilot-scale study
conducted with the Air-O-Fan did not show 6 LR on concrete (3 applications achieved a 4 LR), the
equipment (Air-O-Fan and Dust Boss) sprayed the mock subway system 400 times faster than fogging
or manual spraying, demonstrating that this technology could be applicable to contamination reduction
in a wide-area response.
Extrapolation of the remediation cost for the field study to a large-scale or wide area incident should be
considered with caution. This should, for example, consider the use of large-scale decontamination
solution application methods which, as demonstrated, would significantly speed up the decontamination
process with significantly reduced personnel requirements, and, therefore, reduce the relative cost
contribution of the decontamination cost element in the overall remediation cost.
DISCLAIMER
The U.S. Environmental Protection Agency through its Office of Research and Development directed
and managed the research described herein under several contractual agreements listed in the references.
This study was partially funded through the Underground Transport Restoration Project by the U.S.
Department of Homeland Security Science and Technology Directorate under interagency agreement
No. RW-7095866901. Compilation of this technical information was conducted by Booz Allen
Hamilton under contract EP-G13C-00404. This summary has been subjected to the Agency's review and
has been approved for publication. Note that approval does not signify that the contents reflect the views
of the Agency. Mention of trade names, products, or services does not convey EPA approval,
endorsement, or recommendation.
REFERENCES
1.	U.S. EPA (U.S. Environmental Protection Agency). 2015. "Summary of the Effectiveness of
Volumetric Decontamination Methods as a Function of Operational Conditions." (Technical Brief.)
EPA/600/S-15/190. Washington, DC: U.S. Environmental Protection Agency.
2.	U.S. EPA. 2015. "Surface Decontamination Methodologies for a Wide-Area Bacillus cmthracis
Incident." (Technical Brief.) EPA/600/S-15/172. Washington, DC: U.S. Environmental Protection
Agency.
3.	U.S. EPA. 2016. "Decontamination of Subway Railcar and Related Materials Contaminated with
Bacillus anthracis Spores via the Fogging of Peracetic Acid and Aqueous Hydrogen Peroxide."
EPA/600/R-16/321. Research Triangle Park, NC: U.S. Environmental Protection Agency.
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4.	U.S. EPA. 2007. "Guidance on Test Methods for Demonstrating the Efficacy of Antimicrobial
Products for Inactivating Bacillus Anthracis Spores on Environmental Surfaces." Federal Insecticide,
Fungicide, and Rodenticide Act (FIFRA) Scientific Advisory Panel (SAP) Meeting Minutes No.
2007-05. Arlington, VA.
5.	U.S. EPA. 2017. "Subway Railcar Decontamination with Methyl Bromide: Decontamination of a
Subway Railcar using Methyl Bromide Fumigant on Bacillus anthracis Sterne Strain Spores."
Consequence Management Advisory Team Report. Available at https://www.epa.gov/emergencv-
response/subwav-railcar-decontamination-methyl-bromide. Last accessed August 31, 2018.
6.	U.S. EPA. 2016 "Chlorine Dioxide Fumigation of Subway Materials Contaminated with B.
anthracis Surrogate Spores: Impact of Environmental Conditions and Presence of Dirt and Grime on
Decontamination Efficacy." EPA/600/R-16/038. Research Triangle Park, NC: U.S. Environmental
Protection Agency.
7.	U.S. EPA. 2017. "Decontamination of Subway Infrastructure Materials Contaminated with
Biological Spores Using Methyl Bromide." EPA/600/R-17/187. Research Triangle Park, NC: U.S.
Environmental Protection Agency.
8.	U.S. EPA. 2017. "Underground Transport Restoration (UTR) Operational Technology
Demonstration (OTD)." EPA/600/R-17/272. Washington, DC: U.S. Environmental Protection
Agency.
9.	U.S. EPA. 2017. "Evaluation of Commercially-Available Equipment for the Decontamination of
Bacillus anthracis Spores in an Urban Subway System." EPA/600/R-17/156. Research Triangle
Park, NC: U.S. Environmental Protection Agency.
CONTACT INFORMATION
For more information, visit the EPA Web site at http://www2.epa.gov/homeland-security-research.
Technical Contact: Lukas Oudejans (Oudejans.lukas@epa.gov)
General Feedback/Questions: Amelia McCall (mccall.amelia@epa.gov )
U.S. EPA's Homeland Security Research Program (HSRP) develops products based on
scientific research and technology evaluations. Our products and expertise are widely used in
preventing, preparing for and recovering from public health and environmental emergencies
that arise from terrorist attacks or natural disasters. Our research and products address
biological, radiological, or chemical contaminants that could affect indoor areas, outdoor areas,
or water infrastructure. HSRP provides these products, technical assistance, and expertise to
support EPA's roles and responsibilities under the National Response Framework, statutory
requirements, and Homeland Security Presidential Directives.
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U.S. Environmental Protection Agency
Office of Research and Development
EPA/600/S-18/286
October 2018

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