The Energy of Innovation

NATIONAL AND HOMELAND SECURITY

Continued next page

I

n the United States, 

tens of thousands of 

cargo containers – most 

the size of a rail car – enter 

the country every day through 

one of 93 maritime ports. 

Each container holds a surplus 

of products ranging from 

clothing to plasma televisions 

and medical equipment bound 

for places like superstores and 

hospitals. 

But since Sept. 11, 2001, concerns have been raised about 

how best to prevent dangerous 

materials or contraband items 

from being smuggled into the 

country alongside the millions 

of imported goods. In particularly, homeland security and 

law enforcement professionals are most concerned about 

the potential for illicit radiological materials to make their 

way into the country through 

these shipping ports. 

The traditional counterproliferaton approach has been 

to develop and implement 

a massive cargo-screening 

program with the lofty goal 

of inspecting every cargo 

container being off-loaded on 

the dock. But this approach 

has been problematic, mainly 

due to the limited technical 

advances in screening technology, and the time delay to 

scan each container. 

In addition, new concerns 

about the worldwide availability of nuclear materials 

and technology, combined 

with a rise in global terrorist 

operations, have likely increased the risk of a domestic 

nuclear attack. Nonproliferation experts claim that what is 

needed is a greater emphasis 

on detecting nuclear materials 

before they enter or near the 

95,000-mile maritime border 

of the United States. 

INL’s Solution

To confront this growing challenge, scientists and engineers at the U.S. Department 

of Energy’s Idaho National 

Photonuclear Inspection and

Threat Assessment System

The PITAS system is capable 

of detecting shielded nuclear 

materials in cargo containers 

at distances up to 200 meters. 

An advanced cargo-screening technology for detecting illicit radiological materials 
NATIONAL AND HOMELAND SECURITY

Laboratory are perfecting 

a technology that has the 

capabilities to accurately scan 

cargo containers for smuggled 

nuclear materials at long 

standoff distances. 

Known as the Photonuclear 

Inspection and Threat Assessment System (PITAS), 

this non-intrusive technology 

employs a transportable highenergy linear electron accelerator to channel high-velocity 

atomic photons into a precise 

invisible beam that inspects 

the cargo containers. If nuclear 

materials are present, this process instantly induces fission, 

or divisions, in the atomic 

nucleus of the material. 

Using a series of patented 

cylindrical detectors and a 

standard laptop computer, 

time-dependant gamma and 

neutron signatures emitting 

from the source are analyzed 

for illicit radiological characteristics. And since the PITAS 

technology uses an active 

interrogation process, it can 

detect material that has been 

covertly shielded, radiological 

dangers such as plutonium, 

uranium or thorium can be 

distinguished from simple 

medical or household items, 

which often yield false posiContinued from previous page tive alarms and time delays in 

competing technologies.

In addition, operational factors such as material quantity 

distance to source and the 

accelerator’s electron beam 

energy yields a detection time 

ranging from several seconds 

to two minutes. Any resulting short-lived radioactivity 

around the inspected object is 

either immeasurable or, due to 

the very short time period for 

inspection, has no detrimental 

effects. The PITAS system is 

operated using remote Ethernet transmission, and powered 

by a single gas generator 

which allows it to be operated 

in nearly any environment. 

Parts of the PITAS

The PITAS technology consists of four main components 

including the waveguide, 

klystron, collimator and 

the targeting platform. The 

complete PITAS technology 

Foreign and domestic 

shipping ports will have 

increased protection from the 

PITAS system. 

The PITAS system uses an 

array of neutron and gamma 

detectors to determine the 

presence of nuclear materials. 
NATIONAL AND HOMELAND SECURITY

Finally, the targeting platform 

is a specially designed hydraulic lift and yaw mechanism which raises, lowers and 

directs the side-to-side motion 

of the PITAS system so that 

the energy beam remains on 

target for the desired time 

period. The platform relies on 

laser sighting to appropriately 

align the PITAS system with 

the cargo container. 

Safety

The PITAS technology uses 

many of the same commercial components found in 

today’s modern cancer treatment devices. Even though a 

number of safety features and 

processes are associated with 

operating the PITAS system, 

an object or individual walking through the inspection 

beam would receive about the 

same amount of radiation as 

someone taking several crosscountry roundtrip flights. 

PITAS Benefits

Because the device employs 

transportable technology, it 

is the simultaneous operation 

of these components working 

together in harmony

First, the waveguide creates a 

burst of electron energy and 

injects them into a central 

vacuum tube that runs the entire 

length of the PITAS system. As 

the electrons are being injected 

into the waveguide, a klystron generates a finely-tuned 

radiofrequency that meets the 

electrons. The radiofrequencies 

help direct the electrons into the 

collimator and accelerate them 

to a high rate of speed necessary 

for nuclear materials inspection. 

Once the electrons are inside 

the collimator they are 

converted into high-energy 

x-rays. Excess neutrons 

and absorbed by the collimator which results in a 

bremsstrahlung radiation process similar to a dental x-ray. 

Then, the collimator forces 

the energy beam through a 

small opening in the direction 

of the cargo container. 

The PITAS technology allows 

cargo containers to be 

scanned for nuclear materials 

before ships dock at port.

The complete PITAS system 

includes a linear accelerator, 

collimator, hydraulic platform 

and a series of neutron and 

gamma detectors all operated 

by remote control
NATIONAL AND HOMELAND SECURITY

Dr. James Jones

(208) 526-1730

James.Jones@inl.gov

John Dwight

(208) 526-9590 

John.Dwight@inl.gov

A U.S. Department of Energy

National Laboratory

For more information

08-GA50011-12

Continued from previous page

In 2008, the PITAS system 

will be demonstrated at Fort 

Pickett’s Birchen Lake. 

The PITAS system was developed for the Defense Threat Reduction 

Agency by INL and Idaho State University engineers.

could be stationed at random locations along desired 

shipping routes or onboard 

military vessels in a pointand-shoot configuration. 

Fort Pickett Demonstration

In association with the 

Defense Threat Reduction 

Agency (DTRA), INL scientists and base personnel from 

Fort Pickett near Blackstone, 

Va., will demonstrate the ability of the PITAS technology 

in September 2008. A series 

of tests is currently scheduled 

to determine if the PITAS 

technology can quickly and 

accurately detect shielded and 

unshielded nuclear material at 

a distance up to 200 meters. 

Using Fort Pickett’s Birchin 

Lake, three inspection configurations containing forms 

of nuclear material will be 

stationed afloat in the water 

channel. The PITAS technology will be stationed on the 

west side bank of the lake. 

Under strict environmental and safety guidelines, a 

short high-energy photon 

beam will be directed at each 

floating platform and used to 

positively confirm whether 

the inspected objects contain 

sample nuclear materials.

The PITAS system offers several advantages

over competing technologies. 

•	 Detects at distances up to 		

	 200 meters

•	 Operates remotely from 	 	

	 command center

•	 Detects within seconds or 		

	 minutes	

•	 Offers nonintrusive, 	 	

	 noncontact technology

•	 Uses high-energy 25-30 	 	

	 MeV accelerator

•	 Leaves no lasting impact 	 	 	

	 or residue signature

•	 Controls dose on target 	 	 	

	 with built-in collimator 	 	 	

	 and accelerator operation

•	 Detects shielded materials

•	 Yields superior accuracy 	 	 	

	 with pulsed operation and 		 	

	 laser targeting	

•	 Distinguishes between	

	 plutonium, uranium	

	 and thorium