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BGA Oe GAO

Highlights aa 9401030 een

Why GAO Did This Study Passenger ral systems are vital to Infrastructure, providing

spproximately LÍ mllon passenger tes each weekday Recent

terrorist attacks on these systems ‘round the workd-sich an Moscow, Rama 2010 highlight th vunoraiy ofthese systems ‘The Department of Homeland Securit (IIS) Trataportation

Security Administration TSA) 5 the primary federal ent

Tene for ing Pevener rallspstems

In response tothe Legalative Branch Appropriations Act for ‘sca year 200% GAD conducted a leche sesame! that

reviews 1 the avalabity of txplosies detection technologies ai th ghi to help secure the

Dassongor al eneronment, and 2) ey operational and poly factors atinpact there ot emotes Aletection technologies in the passenger ral eniroumnt GAO aor ent reports on varios txplesves detection technologies fi convened a panelot experts

federal technolo, and passonger rallndsty officals GAO also, interiewed ofa fom DIES and the Deparment of Dense, Energy, Transportation, a Justice thos technologies and thee ppleabll to passenger ral {GAO provide rat of this report tose departnent for comment Four departments prove Eehiieilconteesd Vhich te Incorporated as appropriate err reat Sect Nh ys LS TECHNOLOGY ASSESSMENT Explosives Detection Technologies to Protect Passenger Rai

What GAO Found

Avaroty of explosives detection tochnologes are available or in development that could help secure passenger rail ystems, While these technologies show promise in certain envionment, thet potential talons in the ral

Environment need tobe considered ad hei ise tallored to dvd ril sjstems, The established technologies, such as hantheld, desktop, a ít based trace detection systems, and x-ray imaging systoms, as well as canines, have demonstrated good detection capability with man conventional ‘explosive heats ad some ae in use in pansenge rll today, Newer technologies, such as explosive trace portals, advance imaging technology, find standoff detection systems, while acai, are in varios stages of ‘maturity and more operational experience would be rquired to determine thle Mkely performance if deployed n passenger rll When deploying any of these technologie to secre passenger ral ef important to take into account the inherent linlaions of the underving tetas a Wel a8 bother considerations such as sreoning throughput, mobility aed durability, ‘and physical spac limitations in stations

GAO tance waking recommendations, buts raising various policy considerations For example, in lion to hove well technologies detoct explosives, CAO's wor, in consultation with alan technology experts ‘Mentiied several key operational and policy considerations impacting the role that these technologes ean payin securing the passenger rll environment Specifically, while thee sa shared responsibility forseearing the passenger rileavionment, the federal government, inching TSA, and passenger ail ‘operators have differing roles, which could complicate decisions to fund and Implement explosives detetion technologies For exatple, TSA provides fustance and some funding for passenger rll secunty, but ral operators thomselves provide day-t-tay-seeuity of the systems In akin, risk "management priniples could be used to guide decisionmaking elated fechnology at other security measures and target imited resourees to those areas at greatest isk Moreover, securing passenger rll nvolves multiple security measures, with explosives detection technologie just one of several ‘components th plieymakers ean considers pat of the eral cary environment Furthermore, developing concept of operations for using these technologies and responding to threats that they may Identify Would help Dalance security with the need to maintain te efficient and fee lowing movement of peopl A concept of operations could inehides response plan {or how rail employees shold react an alarm hon a particular technology detects an explosive, Lastly, in determining whether and how to implement those technologies, federal agoncles and ral operators vil kel be

confronted with challenges relate tothe costs and potent privacy and gal Impliations of wing explosives detection echnologies

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Contents Letter i

Background -AVariewy of Explosives Detection Technologies Are Available or in 7 Development That Could Help Secure Passenger Rail Systems—

Tailored to the Needs of Individual Ral Systems—but

Limitations Exist mỹ

Several Overarching Operational and Policy Factors Could pact, the Role of Explosives Detection Technologies in the Passenger

Rall Enviro 48

Concluding Observations mi

Agency Comments and Our Evaluation nơ

‘Appendix I Scope and Methodology w

‘Appendix IT GAO Contacts and Staff Acknowledgments w

Tables

‘Table I: Somme Trace Explosives Detection Methods am ‘Table 2: Description of Advanced Techniques for Cary-on Baggase Explosive Ssstems a ‘Table: Passenger Hall Operators Inerviewed During This Engagement SE Figures

Figure 1: Geographie Distribution of Passenger Rall Systems and ‘Amirali he United Sates „ Eigare 8 Example of Typical Metropolitan Heavy Rail Station w Figure & Typical Large Intermodal Passenger Rall Station

Figure Example af a Typieal Outdoor Commuter of Light Rll Station 2 igure Selected Security Practices in the Passenger Rall Environment tr Figure 6: Explosives Detection Technologies Used 0 Screen People anu Thele Carry-On Bagsage ”

igure 7: Examples of AIT porta images 35

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“Abbrevintione ARP Arr ANEO, APTA, aD ATE ATSA cCTv GÓNGPS cr PHS bop DoE, bow EDC FT FEMA, Fata Fra, ka BNE ND HWX HSIN ep Ns SHEDDO LANL MARC MS NEDCTP NIPP, NPPD NHC NSTS PATH mpiying fluorescent polymer Advanced Imaging Technology ‘ammonium miraleluel ot

“American Public Transportation Association ‘Bureau of Alcohol, Tobacco, Fitears, and Bxplosives Advanced Technology Aviation and Transportation Security Act of 2001 closed ete television concept of operations ‘computed tomography Department of Homeland Seeurity Department of Defense Department of Bnergy Department of Justice explosives devection canine explosive trace porta

Federal Bivergency Management Administration Federal Rsiiroad Administration

Federal Transit Administation ¬

homemade explosives

mm tlahg drlctranioterazine

Homeland Security Information Network Iinprovised explosive device

Ton mobility spectrometry

Joint nprovised Explosive Device Defeat Organization los Alamos National Laboratory Maryland Avea Regional Commuter

ass spectrometry National Explosives Detection Canine Team Programs National Infrastructure Protection Plan

National Protection and Programs Directorate National Research Connell

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SEMTAP Security and Emergency Management Technical Asisiznce

Progra

SNL Sandia National Laboratories TATP Triacelone tiperoside THs TNT, terahertz Ininitrozotuene

TRÀ TSSS? Transportation Sistems Sector Specific Plan Transportation Security Administration ‘ser Transit Security Grunt Program

TSWG ——Technieal Support Working Group

MPR Viste Incermodal Prevention and Response

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& GAO

Tnieed States Gove vent Accountabiliy Office

July 28,2010

"The Honorable Ben Nelson ¬ "The Honorable Lisa Murkowski Ranking Member Sabcomaitee on Legislative Branch Committe on Appropriations United States Senate

‘The Honorable Debbie Wasserman Schulte Chaieman

‘The Honorable Robert 8, Aderholt Ranking Member

Subeomunltee on Legislaive Braned Committee on Appropriations House of Representatives

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209 fatalities highlight the vulnerability ofthese systems Additionally, {he administration's Transhorder Security Interagency Policy Commitee, Suetace Transportation Subcommutiee's recently sued Surface

"Transportation Security Priority Assessment stated thatthe nation's ‘ansportation network was at-an elevated risk of attack and that reeent plots against passenger eal highlight the lengths terrorists will goto defeat security measures put in place after September 11, 2001” Another theeat

acing passenger rail systems are chemical al biological weapons While there have been no terrorist attacks against S passenger rll system's to date, the systems are vulnerable to aleack in part hecatse they rely on 0,

‘pen atehivectre that is difficult 16 monitor and seevre deta is rAuHip]e access points, nbs serving multiple carers and, in sone eases 0 barren to aceese Further a altack on these systems could potentially Jead to casualties due to the high nunsber of daily passengers, especially using peak commuting hours and result in serious economic disruption ‘and psvehotogial impact

‘Day-to-day responsibility for securing passenger ral systems falls on passenger rail operators, local Iw enforcement, and state and local governments that oxen portions ofthe intastmetate While several entitles Diya role tn heiping to fad an secure U.S passenger Hl s9ierts the Department of Homeland Securiy’s (DHS) Transporcation Security Administration (PSA) isthe primary federal ageney responsible for ‘overseeing security for these ystems and for developing 2 national Srateay and inpleinentig programs to enhance thelr security The Department of Transportation's (DOT) Federal Transit Administation (FEA) and Federal Railroad! Administration (FRA) aso provide support to ‘al operators by providing (echnical assistance in conducting threat and ‘ulnerability assessments and developing and providing taiving coutses {or rail operators Additionally, several other DHS components conduct, threat and vulnerability assessinenis of passenger rail systems, research and develop security teehmologies for these systems, and develop Security training programs for passenger rail employees We have previously reported, most recenty in June 2000, on federal and industry efforts to seeuce passenger ral systems and have made recommendations for

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-arengthening these efforts* DHS generzly agreed with these recommendations and is taking action to implement them,

-Avariety of security measures, including technologial measures, have been and are being considered by federal policymakers and rail operators as par ofa layered approach o strengthening the security of passenger ‘all systems, particularly in the area of protecting against the threat of ‘explosives, Explosives detection technologies have been tested and Implemented for sereening passengers and baggage in aviation and building security, Further, the US military uses some of these

technologies, among other things, detect the presence of improvised ‘explosive deviees (ED) in raq and Afghanistan However, these technologies have been tested and implemented less frequent in

passenger rail systems Ths is due in part to the open nature of passenger all systems, which does not lend ise to people and baggage sereening Also, thete i relatively ess finding available to support the purehase and ‘maintenance of such equipment compared tothe funding available for ‘commercial aviation security in which the federal government plays @ larger role Because ofthe potential impact of implementation of «explosives deteetion technology on the open nature of passenger rll system, weiing all operator needsand technological effectiveness of ‘explosives detection technology against the relative costs and impact on rl operations is important Additionally, because these explosives detection technologies tend tobe expensive, ral operators may Look to ‘other fining sources, sch asthe federal government, 10 assis ln implementing these teehnologies,

Inthe Senate report accompanying the proposed bill for the legislative brane seal year 2008 appropriation, the Senate Committee on Appropriations recommended the establishment of a permanent technology assessment function within GAO In dve 2008 Consolidated

Sori Ky Aetions lave Roos Tako Buhance Masa Trot ating, D.C June 00) al ese Rat Sour

‘i avatip Rent o Pre nt Guhe Sowiy or, GXOSG Wamingon I September 209),

"x BD ina deve fit an proved manne that organi te dein ` tp Ne 100, 81248 00),

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“Appropriations Act, Congress authorized GAO to use up 10425 milion of mounts appropriated for silaries an expenses for technology

‘assessment stiies After consultation with congressional committees, GAO agreed to conduct a technology assessment on the use of explosives detection technologies to secure passenger rail systems Specialy, this report addresses the fllowing question

1 What isthe availailty of explosives detection technologies and what Isthelr ability to help secure the passenger ral environment” 2 What key operational and poli factors could have an impact on the role of explosives detection technologies in the passenger el

"his report public version ofthe restricted report (GAO-10-590SU) that \we provided to fou on May 28, 2010 DHS deemed some of the information inthe restricted report as sensitive security information, which must be protected from public disclosure Thevefore, this report omits this Information Alhiough the information proxided is tis feport is more limited in seope, it addresses te same questions as the restricted report, Also, the overall methodology used for both reports isthe same

‘Ta determine what explosives detection technologies are available and ‘her ability to help secure the passenger rail environment, we met sil, ‘experts an officals on explosives detection research, development, and testing, and reviewed test, evaluation, and pilot reparts and other

documentation fom DAS Sclence and Technology Directorate, including {he Transportation Security Lahoratory; TSA; several Department of Defense (DOD) componens, including the Naval Explosive Ordnance bisposal Technology Division (NAVEODTECHDIV), the Technical Support Working Group (TSWG), and the Joint Improvised Explosive Device Deteat Organization (IEDDO); several Department of Enetss (DOB) National Laboratories involved in explosives detection testing, researc, and development ineluding Los Alamos National Laboratory (AN), ‘Sandia National Laboratories (SNE), andl Oak Ridge National Laboratory (ORNL, and the Department of Justice (DOS) because ofits expertise la ‘explosives detection, We also observed a TSA pilot test ofa standoff ‘explosives deteetion system a a rai tation thin the Port Authority rans-Hudson passenger ral system In addition, we interviewee several

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_eRhfeeluret of explosives detection technologies and aitended government sponsored demonstrations, a conference, and an academic workshop on explasives detection technologies, We also interviewed dovernment officials involved with securing passenger rail in the United Kingdom, We visited six domestic passenger rail locations, two of which "were involved in testing various types of explasives detection technologies ‘either observe the cesting or discuss the rests of these tests with

‘operutars The specie locations we visited are listed in appesi , In determining which explosives detection technologies were available and able to secnre the passenger ral environraent, we eonsidered these technologies avallable today or deployable within 5 years, technologies ‘whieh could be used to screen ether passengers or their eary-on ites

and technologies which were sao to use when deployed in public ates In ‘determining the eapabiltes and limitations of explosives detection

{echnolagies we evalnaced thelr detection and sereening throught performance, reliably, availabilty, eos, operational specifications and possible use in passenger ral, We also restricted our evaluation to those {echnolozies which have been demonstrated to deteet explosives shen tested against performance parameters a8 established by government and

rltary users of the technologies

We also obtained the views of various experts and stakeholders during ø ‘panel discussion we convened with the assistance ofthe Nasional Research Com (NRC) August 2008 (eveatier referred to 38 the ‘expert pare), Panel attendees included 23 experts ant officials from acalemia, he federal government, domestic and forejzn passenger rail Industry organizations, technology manufacturers, national laboratories, and passenger rll industy stakeholders such as local law enforcement “officials and domestic and foreign passenger rail operators During this reeling, we discussed the aalablity and applicability of explesives detection technologies forthe passenger rail environment and the ‘operational and poly impaeis associated with implementing these technologies in the rll environment While the views expressed during this panel are noc aeneralizable across al fies yenresented hy offs in attendance, they dit provide an overall summary ofthe eurent availability land effectiveness of explosives detection technologies and industry views fn their appicabily to passenger ral

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‘Modal Annex tothe Transportation Systems Sector Specific Plan, and ‘other documentation, including DHS reports summarizing explosives detection technology tests conducted in passenger rail o better

‘understand the role and impact that these technologies have in the passenger rail environment.’ We reviewed relevant laws and regulations szoverning the security ofthe transportation sector asa whole and

passenger rail specifically, including the Implementing Recommendations ‘ofthe 11 Commission Act We also reviewed our prior eports on passenger rail security and studies and reports conducted by outside ‘organizations related to passenger ral or the use of technology to secure passenger rail such a the National Academies, Congressional Research Service, and others to bette undersland the existing Seeurly measures used in passenger rail and operational and poliey issues During our interviews and expert panel mentioned above, we also discussed and ‘dentfed officials views related tothe key operational and policy issues of using explosives detection technologies to secure passenger ral While these views are not generalizable o all industries represented by these officials, they provided a snapshot ofthe key operational and policy views

uring our vis to 6 rll operator locations involved in explosives

detection testing, we interviewed officials regarding operational and policy Issues related to technology and observed passenger selected these locations because they had completed or were currently rail operations We

conducting testing ofthe use of explosives detection technology Inthe ail envionment and to provide the views ofa exoss-ection of heavy rll, ‘commuter ral, and light rail operators While these locations a officials! ‘views are not generalizeable tothe enire passenger rail industy, they provided us with a general understanding of the operational and policy

{sues associated with using such technologies in the rail environment In Addition, we utlized information obtained and presented in our June 2008 report on passenger rail security," For that work, we conducted site visits, or interviewed security and management officials from 30 passenger rail agencies cross the United States and met with ofcials from two regional {ransit authorities and Amtrak The passenger rll operators we visited or Interviewed for our June 2009 report represented 75 percent ofthe "The TanporiatonSptms Soc Spee Pan documenta progamen to bed "No 15, 21 Sa 200 (Aug 9,0

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‘ation’ total passenger tll ridership based on the information we ‘blained tron the FTAs National Transit Database Public Transportation Association, Foradil information on our and the Anterican scope and methodology plesse see appendi L

‘We condueted our work from August 2008 through July 2010 in

accordance with all setions of GAO's Quality Assurance Framework that are relevant to Teetnologs Assessments The framework reguites that we bilan and perform the engagement to obtain sufficient and ayproptiate evidence to meet our stated objectives and to discuss any Linations 10 ‘out work We believe thar the information and data obtained, and the analysis eondueced, provide a reasonable basis for an Sidings ancl ‘comelsions inti produc,

Background

Overview of the US

Passenger Rail System States jn 28." The nation’s passenger ral systems inelite al services ‘designed to transport customers on toca ad regional routes, sich 38 Passenger ral systems provided 10 billion passenger rips in the United heavy ral, commuter ral an light ral services Tleavy rail systers— subway systems lice Nev York City’s transit system and Washinston, DC's Metro—typically operate on fixed rail lines within a metropolitan area and have the capacity fora heasy volume of tafe Cazomnter val ‘systems typically operate on railroad tacks and provide regional service (ea, between « central city and adjacent suburbs), Light rai systems are

‘ypeally characterized by lightweight passenger ral cars that operate on track that isnot separated from vehicular traffe or much of the way All apes of passenger rll systems inthe United Sates are typically owned and operated by public sector entities, soeh a state and regional transportation uuriies,

Amurak, which provided more than 27 milion passenger trips in fiscal year 2008, operates the nation's prinaay imercky’ passenger rll ana serves ‘ore than 500 stations in 46 states andthe Distriet of Columbia.” Arnrak ‘operitesn more than 22,000 mile network, primary aver leased freight

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‘allroad tacks I ation ‘of track, primariy’on the “Northeast Corridor” belseen Boston ad to leased wacks, Amira owns about O50 wiles Washinaton D.C, wich caries about (wo thieds of Amteak’s total

dership Stations are owned by Amtrak, feiht cariers, muniipalites, nd pritate entities Amtrak also operates commuter rail seviees in ‘certain jurisdictions on behalf of state and regional transportation authorities, Figure J identifies the geographic location of passenger rail

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Passenger ral operators that we spoke to and that attended our expert ‘panel hited that rai tations in the United States generally al ho one ‘of thvee categories:

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‘metropolitan areas They are usually space constrained and lorated either ‘underground or on an elevated platform and serviced by heavy ral Entry {othe stations s usally controlled by turnstiles and ater ehokepoints Many of the subway sations in New York Cay and elevated stations in Chicago are examples of these types of stations See figure 2 far an ‘example ofa typieal heavy rail station

Figure Exanpe ot Types Hevopotian Hen Bal Staton

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space constalned and access is usually restricted either by tastes or naturally apeuring chokepoints sich as escalators oF doorways leading {cal platforms Examples ofthese (pes of stations include Union Station in Washington, D.C See figure 3 for an example of ypIeal 1a sternal tation Figures yen Passenger Ran Sion

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‘Virgina and the Maryland Area Regional Commuter GHAR) tations in Maryland See figure 4 for an example ofa commuter or light rail station Piguet Bony oe TP rOutdoor conmuterer ight el Staten

Passenger Rail Systems Are Inherently Difficult to Secure and Vulnerable to Terrorist Attacks,

Particularly Against the ‘Threat From Explosives

"To date, US passenger rail ystems have not been altacked by terorsis However, according to DHS, terrorists effective use of IEDs in rll attacks elsewhere in the world suggests that IEDs pose the greatest threat to US ‘al systems: Rail ystems in the United States have also received heightened attention as several alleged terrorists’ plots have been

uncovered, including mie plots against systems in the New York City area Worldwide, passenger rll systems have been the frequent target of terrorist attacks According to the Worldwide Ineldents Tracking System ‘maitained by the National Counter Terrorism Center, from January 2001 ‘through July 008 there were 520 terrorist attacks worldwide asain passenger railtarges, resulting in more than 2,000 deaths and more than £9,000 juries Terrorist attacks include a 2007 attack on a passenger train in India (68 fatalities and more than 13 injuries); 2008 ataek on London's underground rail and bus systems (62 fatalities and more than 700 {juries}, and 2004 attack on commer rail rains in Madrid, Spain (191

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Multiple Stakeholders Share Responsibility for Securing Passenger Rail Systems

Tatalities and more than 1,800 injures) More recently, in January 2008, Spanish authoriies arrested 1 suspected terrorists who were allegedly ‘connected to a plot to coneit terrorist attacks in Spain, Portugal, Germany, and the United Kingdom, ineluding an attack on the Barcelona retro, The most common means of atlack against passenger ral targets thas been through the use of IEDs including attacks delivered by suiide omens

According (o passenger sail operators, the openness of passenger ral systems can leave them vulnerable to terrorist attack Further, other ‘characteristics of passenger ral systems—high ridership, expensive Infrastructure, eonomie importance, andl location in large metropolitan arcas of tourist destinations make them sttretive targets for terrorists Dbecause ofthe potential for mass casualties, economie damage, and disruption Moreover, these characteristies make passenger rail ystems Re to secure Iv adaition, the multiple access points along extended routes make the costs of securing each location prohibitive Balancing the potential economic impacts of security enhancements with the benefits of Such measures isa difficult challenge

‘Securing te nation’s passenger ral systems isa shared responsibly requiring coordinated action on the part of federal, state, an local sovernments; the private sector and passengers who nde these systems Since the September 11, 2001, cerzorist atacks, the role of she federal szovernment in secuing the nation’s transportation systems has evolved In response to atacks, Congress passed the Aviation and Transperation Security Act (APSA), which ereated TSA within DOT and conferred tothe agency broad responsibility for overseeing the security af all modes of ‘wansportation, mneluding passenger rai." Congress passed the Homeland Security Act of 2002, which established DIS, transferred DHS, and assigned DIS responsibility for proteting the nation Fem TSA from DOT to terrorism, including securing the nation's transportation systems“ TSA is supported in ts effons to secure passenger rail by other DHS entities such as the Naslonal Protection snd Prograns Directorate (NPPD) and Federal Emergency Management Adiinistation's (FEMA) Grant Programe Directorate and Planning and Assistance Branch, NPPD is responsible for ‘coordinating efforts to protect the nation’s most critical assets across all,

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Is industy sectors, including transportation” FEMA'S Grant Programs Directorate is responsible for maaging DBS grants for mass transit PEML’s Planning and Assistance Branch is responsible for assisting ernst ‘agencies with conducting risk assessments,

‘While TSA isthe lead federal sgeney for overseeing the secuty ofall {ranspertation modes, DOT continues o play a supporting role in securing passenger rail estems, In 82004 Memorundun of Understanding al a 108 anmex to the Memoranda, SA, and FTA agreed thatthe te agencies wonld coordinate thei programs and services, sith FTA

providing technical asistaice and assisting DHS with iplenientation of ltssecurity policies, ineluding collaborating in developing regulations affecting transportation security In adtion to PTA, Fedora Railroad Administration (FEA) also has regulatory authority aver commuster ral ‘operators and Ainrak and employs over 100 inspectors who period.ally onitar the implementation of safety and security plans a these syste FRA regulations requise rairoauls tha operate intereity or commer ‘passenger train service or that host the operation of that service adopt and ‘comply witha written emergency preparedness plan approved by FRA"

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DDHS to carry out ä reSearch an đevelopnt€nt pT0Sram to sectre passenger rail ystems

‘State and local governments, passenger rail operators and private industry are also stakeholdersin the aaton's passenger eal security efforts State ‘nd loeal governments might own or operate prtions of passenger rail systems Consequeatly he responsiblity for responding to emergencies involving systems tha run through their jurisetions often flis to siete And local governments though al levels of government are valved in Dassenger rail security, the primary responsiblity for securing the systems test with the passenger tal operators These operators, which ean be buble or private enities, are responsible for adminiscering and managing ‘ster activities and services, including security Operators can directly ‘operate the security service provided or contract fr all or part of he total service For example, the Washington Metropolan Atea Transit Authority ‘operates its vn police force

Federal and Industry Stakeholders Have Taken Actions to Seenre Passenger Rail Systems

Federal stakeholders have taken actions to help secure passenger rail For ‘example, in November 2008, TSA published a fiat rule that requires passenger rail ystems to appoint a securly coordinator al report potential Ureats and sigificane security concems to TSA." Inaiton, TSA developed the Transportation System'sSector Specific Plan (TS-SSP) ân 2007 Lo document the process to be used in carrying out the national Strategie pririties ouiined in the National Infasitctaze Protection Pian (NIPP) and the National Siatexy fr Transportation Security (NSTS) "The

TS-88P contains supporting modal implementation plas for each

transportation mode, incding mass transit and passener ral The Mass ‘Transit Modal Amex prosides TSA's overall strategy and goals for

securing passenger rai and ass transi, and idenifes specific efforts ‘TSA is taking to siren security in chisarea,”

DHS also provides fusing to passenger rail operators for security, Including purchasing and insaling seeurity technologies, through the

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‘Transit Security Grant Program (TSGP) We reported in June 2000 thạc {rom fiscal years 2006 through 2008, DHS provided about $755 milion dollars to mass trast and passenger rail operators through the TSGP Co protect these systems and the public from terrorist attacks.” Passenger ‘all operators with hom we spoke and that attended our expert panel Said that they used these funds co acquire security assets including ‘explosives deteetion canines, handheld explosives detectors, closed reuit television (CCTV) systems, and other security measures

Passenger ril operators have also taken actions to secure their systems In September 2005, we reported that all 32 U.S rail operators that we interviewed or visited had taken actions to improve the security and safety of their ral systems by, among other things, conducting customer

Awareness campaigns; inereasing the number and visibility of seeurity personnel; increasing the use ofeanine teams, employee taining,

passenger and baggage sereening practices, and CCTV and video analytes; and strengthening rll system design and configuration, Passenger rall ‘operators stated that security-related spending by rail operators was based, Inpart on budgetary considerations as well as other practices used by ‘other rail operators that were dentiied through direct contact or during industry association meetings According to the American Public

‘Transportation Association (APTA), in 005, 54 percent of passenger rail ‘operators faced increasing deficits, and no operator cavered expenses ‘with fare revenue; thus, halaneing operational and capital improvements ‘with seeuriy-relaced investments has heen sn ongoing challenge for these ‘operators, Figure 5 provides a composite of selected security practices used inthe passenger rail environment,

Tố.” LÊN 00 0I (aeiesee,DC duc A10) "

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‘Types and Characteristi

of Explosives and IEDs

‘Countering ihe explosives teat to passenger rall sa difieult challenge as here are many types many different igpes of explosives ave loosely categorized as it of explosives ad afferent forms of bors, The commercial, and third category ealled homemade explosives (HME) ‘hecaise they can he constricted with unsophisticated technioues frm everyday materials The military explosives nchule, among others, the

high explosives PETN and DX, and the plastic explosives C-t and Semtex.” The military ses these materials fora variety of purposes sch asthe explosive component of land mines, shells, or warheads They also Ihave commercial uses such as fr demoliion, ll well perforation, ands the explosive filler of detonation cords Miltary explosives ean only be purchased domestically by leiimate buyers” throug explosives

isrtbutors and typically terrorists have to resort to stealing or smugeling toacquire them RDX was used in the Muni passenger ral borings of July 2005, PETN was used by Richard Rei, the "shoe bomber” in his 2001 Attempt to blow up an aircraft over the Atle Ocean, ad wa a80 a ‘component involved in the attempted bombing incident on board Northwest Airtine Flight 258 over Detroit on Christmas Day 2002

Commercial explosives, withthe exception of black asd smokeless powders also ean only he purchased domestealy by legitimate buyers through explosives distributors These are often used in construction oF mining 2etiites and inclu, among others, trinitrotaluene (TN),

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‘The common commercial and military explosives contain varions forms of nitrogen The presence of nitrogen is often exploced by detection {technologies some of whieh look specifically for nitrogen (neo o nitrate ‘roups) in determning fa threat objet san explosive,

HIMES, on the other hand, can be created using houseliold equipment and ingredients readily available at common stores and do nat necessarily ‘contain the fanliarcansponents of eanventinal explosives: On Febrvary 2, 2010, Najbullah Zaz: plead guilty to, among other things, planning to tise TATP™ to attack the New York City sibway system Also, HME sing TTATP and concentrated ydzogen peroxide, for esanpe, were ase inthe

July 2005 London raleay bomnbing, TATP ean be synthesized from hnydrogen peroxide, a strong acid such as sulfuric acd, and aeetone,& hemical available fn hardware stores and found inna polish eraover,

And HMITD ean be syathesized from hydrogen peroxide, a weak acid such ‘a8 citi aed, and examine sold Mel tablets such as those sed to fe Soine types of camp stoves an thal can be purchased in many outdoor recteational stores, ANFO is sometimes misrepresented as 4 homemade ‘explosive sine both ofits constinent parts ammonium nitrate, Fertiiaer, and fuel oll—are commonly avallable

When nsed, for example n terrorist bombings, explosives are only one component of an IED Explosive sters are pieally composed of ‘control systemn a detonator, a booster, and a main eharge The contr system is usally ore moeehantes or electcal in nate The detonator ‘usually contains a sivall quantity ofa primary or extremely sensitive ‘explosive The booster and main chargesare usually secondary explosives ‘which will mot detonate without a strong shock, for example from 8 {detonator IEDs will also have some type of packaging or, n the case of

Suicide bombers, some type of harness or bet co asta the IED 19 the "body Olen, an IED wil also contain packs of metel—sucl as nail, bolts ‘orserews—or nonmetalie material which are intended ta get as shrapnel fr fragmentation, increasing the IED's Italy The varions components ‘fan IED-—and no just the explosive tsel™ean sso he the object of detection

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A Variety of Explosives Detection ‘Technologies Are Available or in Development That Could Help Secure Passenger Rail Systems—If Tailored to the Needs of Individual Rail Systers—but Limitations Exist

‘provides the shock necessary to detonate the main charge The primary ‘charge and the main charge are often diferent types ad categories of ‘explosives, For example, n te atiempred shoe bombing indent in 2004

the detonator was a common fuse and paper-rrapped TATP, while PETN ‘was ihe main charge While inthe pas the initiation hardware TEDs eantained power supplies, switches, and detonators, certain ofthe of many newer HIMES do not require an electieal detonator but can be initiated by an open fame

‘Several different types of explosives devecton technologies could be anlied to help seeure passenger rai, although opcrational eonstrants of ‘all exist that would be important considerations, For example, handheld esltop, and kit explosives detection systems are posable and already in tse in the passenger rail environment Carty-on item explosives detection {echnologies are roatnre snd ean be effective in detecting some explosive devices, Explosive Trace Porals generally use the sume underlying {ecinology as handheld and desktop systems, and have been deployed in aviation with lnited suecess Advanced Imaging Technology (AIT) portals fare becoming avallable but as with race portals, will ikely have only Iinited applieabity i passenger ral Standoff detection technologies promise 2 deveetion eapahilty without impeding the Mov of passengers,

that have several imitations, Canines are eurreily nse in passenger rail systems, generally accepted by the public, and effective at detecting many {pes of explosives: Limiatins in these technologies reset their nore ‘Widespread or more efective use in passenger rail and include finite Sereening throughpit and mobility, potential issues with environmental conitions, and the openness and physical space restrietions of many ral

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Various Explosives Detection Technologies Could be Applied to Help Secure Passenger Rail Systems If Operational Constraints of Rail are Effectively Considered

Tn the passenger rail environment detection of explosives involves the sereening of people and their carry on baggage The different pes of ‘explosives deteetion technology available vo adress these sereening needs ean be divided into twa basic categories There are those based on maging methods, sometimes called bulk detection, and those that are ‘based on tee detection methovs The gosl in bulk detection iso identify ang suspicious indication —anr anomaly-ina bag oF on a person tat ‘night potently ea bomb, These systens, while they ny be wsed ta {detect explosive material are also often sed t detect other arts of &

Domb Although some automated detection zssistance is usualy included, ‘maging based detection systems currently depend heavily on Haed ‘operas in eniying he anomalies licative of a hor

‘Trace detection technologies, onthe exher hand, involve taking plysical sample from a likely source and then analyzing it with ay one of sever ‘fezent techniaues forthe presence of trace particles af explosive raterial.” Importantly, a posiive detection des not neceseiHly indicate the presence ofa bomb hecase the trace particles may just be

contamination from someone having handed or having been wear

‘explosives material Explosices trace detection systems ean often identity the tndivial typeof explosives trace particles present

Bland race detection technology generally serve differen functions and an sometines be paired o peovide a more complete sereening of person sd thei belongings Type tht sereening aecirs h 80 stages First, an inital sereening is done to separate suspicious persons or cry ‘on b8ggag from the rest ofthe passeader flow quickly In almost al cases, fy snonvales detected in inital sereening wil rigger the need for person or bageage to undergo a secondary inspection, va dffezeat ‘ncthods, and typically aside from dhe main sereening Now co confiem oF dismiss the anomaly a8 threat.” Tectmology need not be used in ether Inspection stage For example, behavioral assessment is sometimes used to provide an intial sereening In alditin, Secondary inspection can be a physical pat-dovn ofa person ar hand inspection of earry-on baggage Although explosives detection technology can also be used Seveniag can

5 fac tices ae bone parle yo ilo th aed ee Bing expos

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‘be done on 100 percent of passengers oF om a subset of passengers chosen at random of by sonie selection niethod

Ditferent types of balk: an race explosives detection technology have ‘heen developed over the years to fsdlle both the screening of people and the Sereening of eary-on baggage Generals, equipment falls into eestain ‘ypiealcontiguraions-—laavheld, desktop, hitbased ssiemS, eaey-on Dbaquage inspection systems, explosive trace portals, AIT portals, standoff detection systems, and explosives detection canines.” Cerin equipment thas been designed fr the screening of people, some forthe sereening of cau on baggage, and some equipreent can be use for both (See figure 8)

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Figures commune Contiguration Soom b3 mm ⁄ re

‘Tobe effective, equipment in each ofthese configurations is generally ‘evaluated across several different technical characteristics The first important technical characteristic of an explosives detection system is hhow good iis at detecting a threat Several different parameters are ‘considered to fully express used Co express how often the system gets the detection right, and how a system's ability to detect a threat They are ‘often—and in which ways—it gets the detection wrong, The system cam, ‘et the detection right when it alarms in the presence ofa threat and the percentage of times it does under a given set of conditions scaled the probability of detection

However, other important parameters measure the percentage of times the system gets the detection wrong This can occur in two ways Fist, the

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Handheld, Desktop, and Kit Explosives Detection Systems

‘system can alate even though athvea is not present This scaled a false positive and the percentage of ines it acest a gen unnber of cals is called te false postive rate Tess so cle the false alarm rate or

probmbiliy of fase alarm Second, the system can fil alarm even though a threat is present This ealled a false negative and the

percentage of mes i oceurs in given numberof tials i called the false negative rate

A second key technical eharacterstc for explosives detection systems is screening throughpat, which isa measure of how fasta person a item can be processed throigh the system before the system is ready to accept another person orem, Sereening theoughpst isan important

‘haracteristie to know because it directly impacts passenger delay, an Important consideration when using teefnology in passenger ra The higher the throughput, che less delay is imposed on passenger flow

‘other important cechnieal characteristics fo consider when assessing anpliesbility of explosives detection systems for use in passenger rail re the system's size and weight, which will impact its mobility, the phystal space needed to operate the system, and the system's susceptibility 10 ‘rsh environmental conditions, Understanding the system's east is aso

Handheld, desktop, and kit explosives detection systems are portable systenis that ae designed co deteet traces of explosive particles They have been shown to deteet many explosive substances and are already

"sein passenger ral environments today, generally in support of secondary servening or ina confirmatory tole when the presence of ‘explosives or their rae parteles are suspected

Ina typical usage with handheld and desktop systems, a sample of trace particles eollected by wipins a surface with 2 swab or her collection ‘evice designed for use with the system,” The simple is transfered ate the system and typically heated to vaporize the wace particle, which are ‘hen atau into the detector where they are aalv2ed for the presence of

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‘substances inaeative of explosives: The results of sample analysis are ‘opieally displayed ona readout sereen

Usnsdheld and desktop systems encompass a variety of detection

‘eciniques to analyze the sample and determine iit contains particles of ‘explosive compounds The various underlying techniques include ion mobility spectrometry IMS), amplifying Nuorescent polymer (AFP), chensluineseenee, and colorimestic Many handheld and desktop ‘stents are generally based on IBIS technology a mature and wel ‘understood method of chemical analysis This echnigue consists of Jonigng the sample vapors and then measuring the mobili of the fons as they deft ina electric eld, Bach sample ion possesses unique

iobility-—based on is mass, size, and shape—wehich allows forits ‘eificaton.”

‘The AFP technique ubiizes compounds ultraviolet light However, the fuarescence intensity’ decreases in the that fuoresce when exposed to presence of vapors of certain ntrogen-containing explosives, such as TNT Detection methods based on this principle look for a decrease in intensity ‘ha is indicative of specie explasizes AFP has been shown to havea high level of sensitiity to TNT The chennlluninseence principle is based ‘on the detection of ight emissions coming fran witha" groups La are ound in mang eonventional military and commercial explosives such as

TNT, RDX, PETN, black ponder, and smokeless powder However, chemalutinlscetce by Itself eannot identify any speci explosives because these nitro compounds are present not only ina number of commerval and military explosives, but also in many nonexplesive substances such as fertilizers and some perfunes Therefor, this

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Kirbased explosives deteetion systems generally use colorimetric ‘echniques this metho, the detections based on the Tact that a specie compound, when treated by an appropriate color reagent, Produces a color it is characterise of this compound, The sample i faen by swing the target objec, typieally with a paper, and then the colorimetric reagents are applied by spraying or dropping them on the paper: The operator deposits chemical reagents ina series and observes ‘olor change’ with cach reagent added This process of adling reagents is Stopped wien a ssible color ehange is observed bythe operator The ‘opezztor decides whether there are any trace explosives preseat by ‘visually marching the color ehange observed toa slandaedlzed sheet of colors Table 1 describes some ofthe trace explosives detection methods described above ‘Tibte 1 Some Trace Explosives Detection Netiode

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In comparative Sudies aver dhe lat 8 years, the Naval Explosive

Onlinasce Disposal Techwology Division showed that IMSbased handheld and desktop systems are capable of detecting many conventional military and commercial explosives that are nltoget-hased, such a8 TNT, PETN, and RDX NonIMS based ceehniques such as aplifying luoreseent polymer and ehemuluminescence based technigits are able to additionally

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.đetect ANPD, smokeloss po/đet and ta nittae However, a report sponsored by DOD's Techical Support Working Group shows that most ‘of dese syscems explosives had! diffiuity in detecting cestan other types of

Preliminary results from an ongoing comparative study of kitbased erection systems sponsored by the Transportation Securlty Laboratory have shown that these systems can detect the presence of nisogen when there is suficent quantity of explosive sample (im sinall-bll” or visible amounts) avalable for analysis For example, ki-based systems were able tocorreety ideniy the presence of nitrogen in a variety of diffecent threat aerials,” Additnaly, kicbased systems have been shown to be

susceptible to false lars when challenged with substances such as soaps and perfumes, among others

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Canyon Baggage Explosive Detection Systems

Ivan open environment over a range of external emperature, prESSUE, And hulnidity conditions.”

A survey by the Transportation Security Laboratory in 2008 showed a large ‘number of manufacturers of haadheld, desktop, and portable kit-based devices available on the commercial market © Although costs are & consideration—for example in addition intial evst, there are routine risitenaince casts and the eos! of consumables sich asthe swabs use {or sampling—for determining whether to make future deployments of handheld, deskiop, and kit explosives detection systems, these

technologies are already being used inthe passenger rll environment and are expected to continue to play arole there,

CCarry-on baggage explosive detection systems are based on x-ray imaging, ‘technology that has been in use for more than a century Screening Systens incorporating the technology have been 0seđ In comercial Aviation for more than 39 years, n pat, heeause they serve a dul purpose Jaye ate analyzed for guns and other weapons the sume tne they are analyzed forthe presence of materials that may be explosives Beeause these images do not uniquely Menity explosive material, secondary sereening is requlted 9 positively Wdentiy the materials as explosives Sinale-energy xray systems are useful for detecting some bomb components They are, however, not as nsehil for the detection of ‘explosive material iisell Advanced techniques add youltple views, đua x: ray energies, backseaiter, Table 2} to provide the sereener with ational formation La he, and computed tomography (CT) features (see Identity IEDs, Systems with one or more advanced techniques, mike ‘views: dual energies, and backseaiter, bit not CT are called advanced {echnology (AT) systems o distinguish them from CT AT systems erable more accurate identification of explosives without the additional expense ‘of CT Bure, the additonal ssformation can be used to asstomatcally detect explosive materials Carry-on bageage explosive detection

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“Ttanspotisglon Sectmly 14borstary tao qualified" several diferent models ‘of earty-on baggage explosive detection systems manitfacsured by several ehdore fur use in commercial aviation Many of these systems are in use very day a airports inthe United States

‘inte Deserpton ot Asvanced Techniques or Con vn Gaggnge explore Systems

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Carry-on baggage explosive deteetion systems are eective in detecting IEDs that use conventional explosives when sereeners interpret the |mayes as was demonstrated ina Transportation Security Laboratory ai

‘cargo screening experiment where five different models of currently fielded AT bagaage explosives detection aystens were used ta sereen al sight categories of TSA defined cargo,

In addition, DES Science and Technology (S&T) Directorate provided another comparison of sereener performance to antomatie detection performance ina 26 pilot progran atthe EXchange Place Station i the Por Authority Trans tfudson (PATH heasy ral system Phase [ofthis hilt evalsted the effectiveness of offthe-shelf explosives detection ‘capabilities that were adapted rom current aisport checkpoint screening {echnologies and pracedves The carry-on baggage explosive detection

‘equipment was operated in the sstommated Yeas detection mode to

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Tlnhglze aSSenget del SgsIeh effectiveness was tested by the wse ofa red teat, an adversary tean that aitenpted to eireunivent the seeanty reasures Whe the results were highly sensitive and not diseussed in the pilot program repor, the false alarm rate was found to below

‘carry-on bagsage explosive deteetion technologies have operational issues ‘hat limit thee usefulness in passenger rail security These systems are used in checkpoinss and thelr acceptability will depend upon the tolerance for passenger delay At checkpoints, 100 percent screenings possible up tothe throughput capaciy ofthe screening equipment; heyond tha rate,

ditional sereening equipment aad personnel or setective (ess than 100 percent) sereching is required During SAT's severing in the PATHE ‘ster passenger ral plot, 2 maxinnin snelesystersthroushpat of 400 ‘bags per hour was ineasured with eary-on baggage explosive detection systems operating in automatic explosive detection mode at threst levels Aanpropriate Yo passenger ral, as deseribed above The 400 hags pee hour Single ssstem throughput hada corresponding passenger teoughput of 2025 passengers per hot, With this throng, the pilot was able to

perform 100 percent screening of large bags and computer bags (see below) during the peak rush houeusingrwa carry-on baagage explosive detection systems,

Another closely related challenge associated with checkpoint servening is passenger delas- The S€7 pilot inthe PATH system measated median passenger delass of 17 seconds aul 17.5 seconds respectively depending ‘on wheter or nota passenger's bags set off automated explosive

detection alarms, These delays can be compared tothe 13 second median {ime for tn unscreened passenger to walls through the sereening area The longer delay, when bags set off alarms, was caused by secondary

screening required to confit or deny De presence of explesives Maximum passenger chroughp was achieved when sereening only bags large enorgh anv heavy enon to contain safficient explosives ta damage ‘passenger rai infrastricture When 100 percent screening exceeded the ‘capacity ofthe ssstem, the pilot nsed quene-based selection (o maximize {hroughpnt In quene-ased selection, a eaife director selets passengers for sereenins a long es there is room inthe quene for Une screening process: Using this procedure, the pilot was able ta necommodate PATH's Aesite to Keep queue lengths Below fve passengers

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Explosive Trace Portals

‘carry-on baggage explosive detection 3yem, and provide instructions as required), secondary Seveener, and-# maintenance person, Structures would be needed to protect existing eary-on haggoge explosive detection systems from the challenging passenger ral emsironments, "whieh include outdoor stations that aze exposed to dust and precipitation ‘This is because typieal earry-on baggage explosive detection systems lave gzartious pats tat are not protected from foreign objects up to Linch ix diameter and have no proteetion from water intrusion

Explosive trace portals (HTP) ae used in sereening for access to buildings and, to limited extent, airport checkpoint sereening, The operation of these systems genevally involves ETP and the ETP sensing is presence and, when ready, instructing the a sereener directing an individual to the Individual to enter The pon thea blows shoe puis of air onto the vidual being screened to help dispae particles and atenapts to collect, ‘hese patices witha vacuum system, The particle sample is then

preconcentrated and fed into the detector for analysis The results are Eisplaye 10 the operator as either postive or negative for he detection of ‘explosives Positive ests can display the deceeted explosives and wigger an audible alana

‘Currently teste and deployed ETP use IMS analytical techniques for ‘chemical analysis to detect traces of explosives, similar to those used for Ingndhed aad desktop detectors These techniques are relatively manure ‘hut the operation of IS based RTP in an ojeh ae entonent, sich #8 ‘hat of passenger ral is subject to interference from arabient agents, suc as moisture and contamizants that ean impact a detectors performance dy inectering with is internal analysis process resulting in false readings

Regaress ofthe detection technique used, suampling is major issue for trace detection Generally fetors suchas the explosives’ vapor pressure and packaging, as well as how much contamination is present on an Individual from handing the explosive, affect the amonne of material available for sampling Particular to race paral, factors seh a8 the ‘systems puffer jets and timing, clothing, the location of explosive

contamination onthe body, and human variability impact the effectiveness ‘of sampling, For example, the puffer jets produce to litle pressure,

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‘hey hace ile pact ia improving the trace explosive sana, while too neh pressive resuls in trace explosive particles becoming lost large volume of air that is tfeul to sample effectively In aditon, clothing material and layering ean reduce the available trace explesive signal The location of the explosive trae on the body also impacts the amount of face explosives thatthe aystem will collect

In eboratory testing of BPs in 200, the Naval Explosive Ordnance Disposal Technology Division ested thrve ETP systems’ basie ability to detect trace amounts of certain explosives within the required detection {threshold when deposited on the systems collection ives” While the systems consistently detected sore af these explosives, they were unable todetect others.”

In addition, during laboratory testing on systems from three manufacturers perfornned by the Naval Explosive Ordnance Disposal Technology Disislon in 2004 and the Transporation Security Laboratory foun 2004 through 2007, the systenns dia not meet corrent Naval Explosive Ordnance

Disposal Technology Division or TSA requirements,

In 10 laboratory and aleport pilot tests of FTPs from three manafacnarers| from 204 theongh 2005, the Naval Explosive Ordvance Disposal Technology Diision and TSA also meastted the systems’ throughput laborarory testing, the average throughput without slarns ranged Irom 25605 peaple per minite Diving plot testing in alrpons, the operational ean tlvonghput, whiel nelded alarms, ranged from 0.3 co 1 people er minute aol the operational mean sereeting Hine ranged fro I54 ‘seconds to 222 seconds Although, they may have some applicability for checkpoint seeeening in lower volume ral environments that require passengers ro quene wp, the Unrousht and screening tine of BTS make ‘em impraetical to use for 100 pereent sereening in hah volume ral

‘An ETP system using a differen analytieal technique, mass spectrometry “AIS) for chemial seals has the potential of sigaiieantlylnproving the

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Advanced Lmaging Technology Portals

ahiiy to distinguish explosives from environmental contaminants altho is use na portal configuration is not een tested ithe rail ‘ensironment.” DHS has, however, performed laboratory testing of 80 versions ofan MS-based ETP."

‘other operational issues may binit tele spplicabity le the ral environment GAO found that during te pilot esting in airports, for examnplc the systems didnt meet TSA's elablty requirements dae to “environmental conditions," This resulted in higher than expected "iainlenance costs ad lower than expected operational readiness tne EETPs may have some applicability for eheckpoint sereening in lower volume rl environments cat require passengers to queue up such as Amtrak, ht the Tow thrips and long screening time of ETP male them impraetial to use for 100 percent sereening in high volume rail stations In addition, the large size ad weight of ETPs make them difficult fosranspore and deploy n sists with limited space and also practical for use in any random was)

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‘Currently deployed ATF portals in the aviation environment use ether rillimeter wave" or backscatter x-ray techniques to generate an image of ‘person through their clothing While bth systems generate images of similar quality, millimeter wave has the advantage that it does not produce fonizing radiation Although, aecording o one manufacturer, is

backscatter x-ray system meets al applicable federal regulations and standards for public exposure to ionizing radiation, ystems that don't use fonizng radiation will kely raise fewer concerns

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