Transcript Explosive Detection Technologies

Explosive Detection
Technologies
Usha Kiran Sureddy
Agenda
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Study different types of explosive detection
technologies
– Neutron, Gamma Ray, X-Ray
– Active and Passive
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Analyze commercial applications
– Cargo detection
– Baggage screening
– Vehicle detection
Explosive Detection Technologies
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Gamma Ray Based Systems
– Ionization Chamber
– Pulsed Gamma Ray Analysis
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Neutron Based Systems
– Thermal Neutron Analysis (TNA)
– Fast Neutron Analysis (FNA)
– Pulsed Fast Neutron Analysis (PFNA)
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X-Ray Based Systems
– Transmission
– Backscatter
Ionization Chamber
Passive technology that detects the presence of
radioactivity by measuring electrons and ions
produced by the particle to be detected
 Effective against radioactive materials in small
traces
 Pinpoints the location of the threat by multidimensional detection arrays
 Easy to deploy, high throughput
 Cheaper to install and to maintain
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Pulsed Gamma Ray
Active technology to
detect explosives,
nuclear materials and
chemical agents
 Measures relative
content of nitrogen,
oxygen and carbon
and by identifying
their molecular
weight
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Pulsed Gamma Ray
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Effective against explosives, nuclear materials,
drugs, and chemical agents
Ability to identify the chemical composition of the
materials
Ability to identify the type and location of the
target
Penetration capability
High accuracy
Imaging capability
Multi-functionality
Gamma Ray Technologies:
Applications
Primary application for both these
technologies is the inspection of bulk loads,
such as containers
 Explosive detectors are used at seaports,
airports and borders
 Useful for non-intrusive explosive detection
 Useful to identify the type and the location
of the hazardous materials
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Neutron Based Technologies
These technologies use radioactive sources as
neutron source
 Neutron particles generated by this source
excite the nucleus of the atoms within the
material being inspected, and the resulted
rays are characterized by their intensity and
energy
 Disadvantages
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– System complexity and cost
– System weight
– Radiation hazards
Neutron Based Technologies
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Thermal Neutron Analysis (TNA)
– Slow neutron interaction
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Fast Neutron Analysis (FNA)
– Fast neutron interaction
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Pulsed Fast Neutron Analysis (PFNA)
– Fast neutron pulses interaction
Thermal Neutron Analysis (TNA)
Thermal neutrons are produced by slowing
down fast neutrons generated by sources or
accelerators in specially designed moderators
 Neutron particles generated excite the nucleus
of the atoms within the material being
inspected, and the resulted rays are
characterized by their intensity and energy
 TNA characterizes high explosives by their
nitrogen and hydrogen traces
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Thermal Neutron Analysis
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Advantages
Easiest neutron based
method
High accuracy and
low false alarm rate
Low cost ($1 million)
Detects N, H and Cl
and some metallic
elements
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Disadvantages
Not capable of
detecting ‘O’ or ‘C’
elements
Possible interference
from other elements
Slow throughput
Real time inspection
not possible
Fast Neutron Analysis (FNA)
FNA is based on fast neutron interactions,
mostly inelastic neutron scattering
 Analysis similar to the TNA technique is
employed
 FNA characterizes explosives by their
nitrogen, carbon, oxygen, chlorine traces
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Pulsed Fast Neutron analysis
(PFNA)
Based on pulsed fast neutron interactions with
the nuclei of target
 High energy neutrons help generate spatial
distribution of signal
 Effective in detecting nuclear materials and
metals
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Pulsed Fast Neutron analysis
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Advantages
High accuracy and
low false alarm rate
Detects all kinds of
explosives
Identifies the type of
material
High Sensitivity, 3D
imaging capability
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Disadvantages
High cost
(> $10 million)
Complex system
(more space and labor
requirement)
Requires high energy
accelerator
Shielding requirement
X-Ray Technologies
(Transmission & Backscatter)
Description
Pros
Involve irradiation of a target item
with X-rays, followed by detection
of images created by X-rays that
are either transmitted or
backscattered by the item
2D-3D quality imaging capability
Established in the marketplace
Multi-functionality (contraband,
smuggling, manifest verification)
Effective in Detecting
Cons
Contraband
Weapons
Explosives
(switches, detonators, etc.)
Can not identify the type of
material
Only sensitive to shapes, densities
& absorption patterns of
materials
High false alarm rate (30%)
Low throughput
Transmission Vs. Back-scatter
Transmission Image
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Backscatter Image
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Displays materials
discrimination
Ideal for complex
environments
Reveals fine details
Can’t display materials
discrimination
Penetration of complex
environments
Transmission Vs. Backscatter
Transmission
Backscatter
Summary of Technologies
High
Complexity
PFNA
TNA
X-ray
Pulsed
Gamma
Low
Low
High
Ability to identify specific type of materials
Ideal Technology Features
Operate at various
energy levels
(Less than 1MeV to
50MeV)
Improved imaging
capability
Sensitivity to
different radiation
sources
Ability to integrate
with the legacy
systems
High performance
/price ratio
($10 million per unit)
Successful
Technology
Flexible in size and
shape
Small footprint
(4,000 – 5,000 sq. ft)
Fully automatic
system (no labor
requirement). No
human error, Low
cost
Future Trends
Complexity
High
Traditional X-ray
technologies integrate
with new technologies
to enhance the
detection capabilities
PFNA
TNA
X-ray
Pulsed
Gamma
Low
Low
High
Ability to identify specific type of materials
Market Applications
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Cargo
– Sea cargo
– Air cargo
– Road cargo
Vehicle Screening
 Baggage Inspection
 Other applications
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– People screening
– Medical applications
Summary of Markets
Baggage Screening
Seaport Cargo
Large market size
(Over $4 billion)
Deficiencies of existing
technologies (False alarm rate,
low sensitivity)
Safety and throughput
concerns
Large Market size ($2-$4 billion)
Ineffectiveness of existing tech. in detecting specific
threats
Safety and speed concerns
Border Cargo
Medium market size
($1 billion)
Throughput is important
Imaging quality is crucial to
detect smuggled goods and
narcotics
Market
Potential
Vehicle
Screening
Medium market size
Human Safety
Throughput concern
Air Cargo
Medium market size
($1 billion)
Penetration and multifunctionality
Safety and throughput
concerns
Conclusion
Each technology has its own advantages and
disadvantages
 Speed, precision and safety emerge as
important features of technology
 Combination technologies will prevail
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– Transmission & backscatter, X-rays combined
with other technologies
Thank you!
Q&A?