www.battelle.org

Richter WR1, Sunderman MM1, Rogers JV1, Calfee MW2, Oudejans L2, Lee SD2, Mickelsen L2, Nalipinski M2, Serre S21Battelle Memorial Institute, Columbus, OH, USA 2U.S. EPA, Office of Research and Development, National Homeland Security Research Center, Research Triangle Park, NC, USA

Evaluation of Commercially-available Equipment for the Decontamination of Bacillus anthracis Spores in an Urban Subway System

ABSTRACTThe Underground Transport Restoration (UTR) project was aninter-agency effort aimed to improve the capability for transitsystems to rapidly and safely recover from a wide area biologicalcontamination incident by refining existing methods, tools, andprotocols for characterization, clean-up, and clearance ofcontamination in physical structures. The U.S. EPA, in partnershipwith Battelle, investigated the potential use and durability ofcommercially-available equipment and associated efficacy for theuse in dispensing liquid chemicals at a large scale todecontaminate subway surfaces following a biologicalcontamination incident.

TECHNICAL APPROACH RESULTS

Air-O-Fan D-40R radial sprayerDust Boss DB-30 sprayerMM Sprayers USA MM LG 400

Dust Boss nozzle failure

Air-O-Fan nozzle failure

Durability Test Fixture MM sprayer pump failure

0

20

40

60

80

100

120

10:5

110

:51

10:5

210

:53

10:5

310

:54

10:5

510

:55

10:5

610

:57

10:5

710

:58

10:5

910

:59

11:0

011

:01

11:0

111

:02

11:0

311

:03

% w

etne

ss

Time

AOF FAPH % Wetness

railing

tunnel wall

column back

ceiling

tracks 0

20

40

60

80

100

120

11:1

911

:19

11:2

011

:21

11:2

111

:22

11:2

311

:23

11:2

411

:25

11:2

511

:26

11:2

711

:27

11:2

811

:29

11:2

911

:30

11:3

111

:31

% W

etne

ss

Time

Dust Boss FAPH % Wetness

railing

wall

column back

ceiling

tracks

Durability Testing

Fort A.P. Hill Field Scale Demonstration

System Scale Efficacy Testing (10°C)

Ambient breeze tunnel test facility AOF sprayer and test cart configuration

Liquid inoculation of test coupon Test cart fixture with test materials

Liquid extraction in phosphate buffered saline + 0.1% Triton X100 at 200 rpm for 15 min

Quantitative Enumeration

0123456789

Column Floor Column Floor

Ceramic Tile Ceramic Tile UnpaintedConcrete

UnpaintedConcrete

Log

Red

uctio

n ±

95%

CI

Contact Time Comparison

30 Min Contact

Overnight Contact

012345678

Column Floor Column Floor

Ceramic Tile Ceramic Tile UnpaintedConcrete

UnpaintedConcrete

Log

Red

uctio

n ±

95%

CI

Operational Speed Comparison

1.2 mph

2.4 mph

0

1

2

3

4

5

6

7

Column Floor

Log

Red

uctio

n ±

95%

CI

Repeat Application (Concrete Only)

1 Application

2 Applications

3 Applications

0123456789

10

Column Floor

% R

ecov

ery

1.2 mph Mechanical Removal on Concrete

1 Application

2 Applications

3 Applications

4 Applications

• Dust Boss and AOF tests identified replacement nozzles that mayresult in increased durability.

• Demonstration resulted in 100% coverage at all locations for AOF.• All efficacy testing conducted with ceramic tile resulted in >6 LR,

while no conditions resulted in >6 LR of B.g on unpainted concrete.• Using AOF and application speed of 2.4 mph, 30 min contact time,

151 liters per minute (~40 gal/min) liquid delivery rate, and 3 repeatapplications, each mile of subway tunnel could be decontaminated in2 hours and 45 min using 11,325 L (~3000 gal) of decontaminant.

• Based on findings this would result in >6 LR for ceramic tile and ~ 4LR for unpainted concrete.

TEST OBJECTIVES

Survey of commercially available equipment was conductedresulting in identification of three pieces of priority sprayequipment [MM Sprayers, Air-O-Fan® (AOF), and Dust Boss®].Durability assessment conducted by subjecting selectedequipment to 100 hours of operation with pH-amended bleach(pAB) using smaller proxy equipment to test for materialcompatibilityField scale demonstration conducted using two pieces ofequipment (AOF and Dust Boss sprayers) at a subwayplatform/tunnel at Fort A.P. Hill (FAPH, Bowling Green, VA).Decontamination efficacy testing was conducted withoperationally sprayed pAB against surrogate B.g. was evaluatedat target delivery speeds of 1.2 and 2.4 mph on vertical andhorizontal coupon orientations, and contact times ranging from 30minutes (min) to 12 hours (overnight) for a total of 4 tests.DisclaimerThis study was funded through the Underground Transport Restoration Program by the U.S.Department of Homeland Security Science and Technology Directorate under interagencyagreement (No. 7095866901). The U.S. EPA directed and managed this work through ContractNumber EP-C-15-002, Task Order 007, with Battelle. This report has been peer andadministratively reviewed and has been approved for publication as an EPA document. The viewsexpressed in this report do not necessarily reflect the views or policies of the Agency. Mention oftrade names or commercial products does not constitute endorsement or recommendation for useof a specific product.

KEY FINDINGS

01000200030004000500060007000

0 5 9 15 18 22 28 34 40 47 54 61 67 74 81 88 95 100

Flow

ml/m

in

Hours

Durability Flow Rate DB ControlDB-1DB-2DB-3MM ControlMM-1MM-2MM-3AOF ControlAOF-1AOF-2AOF-3

AOF Nozzle 1 FailureAOF Nozzle 2 Failure

AOF Nozzle 3 FailureDust Boss Nozzle Failure 1-3

MM Sprayer Pump Failure 1-3

EPA Report