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. 1 U.S. Environmental Protection Agency Office of Research and Development EPA/600/S-18/286 October 2018 ------- 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], EPA/600/S-18/286 October 2018 U.S. Environmental Protection Agency Office of Research and Development 2 ------- 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). 3 U.S. Environmental Protection Agency Office of Research and Development EPA/600/S-18/286 October 2018 ------- 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. U.S. Environmental Protection Agency Office of Research and Development EPA/600/S-18/286 October 2018 ------- 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. 5 U.S. Environmental Protection Agency Office of Research and Development EPA/600/S-18/286 October 2018 ------- • 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. 6 U.S. Environmental Protection Agency Office of Research and Development EPA/600/S-18/286 October 2018 ------- • 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. U.S. Environmental Protection Agency Office of Research and Development EPA/600/S-18/286 October 2018 ------- 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 8 U.S. Environmental Protection Agency Office of Research and Development EPA/600/S-18/286 October 2018 ------- • 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. 9 U.S. Environmental Protection Agency Office of Research and Development EPA/600/S-18/286 October 2018 ------- 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). 10 U.S. Environmental Protection Agency Office of Research and Development EPA/600/S-18/286 October 2018 ------- • 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. 11 U.S. Environmental Protection Agency Office of Research and Development EPA/600/S-18/286 October 2018 ------- 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. 12 U.S. Environmental Protection Agency Office of Research and Development EPA/600/S-18/286 October 2018 ------- 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. 13 U.S. Environmental Protection Agency Office of Research and Development EPA/600/S-18/286 October 2018 ------- |