[ RadSafe ] Cell phone automatic radiation detection.

Louie Cueva louie at tgainc.com
Thu Jan 31 18:18:42 CST 2008


Cell phone sensors detect radiation to thwart nuclear terrorism

WEST LAFAYETTE, Ind. - Researchers at Purdue University are working with the
state of Indiana to develop a system that would use a network of cell phones
to detect and track radiation to help prevent terrorist attacks with
radiological "dirty bombs" and nuclear weapons.

Such a system could blanket the nation with millions of cell phones equipped
with radiation sensors able to detect even light residues of radioactive
material. Because cell phones already contain global positioning locators,
the network of phones would serve as a tracking system, said physics
professor Ephraim Fischbach. Fischbach is working with Jere Jenkins,
director of Purdue's radiation laboratories within the School of Nuclear

"It's the ubiquitous nature of cell phones and other portable electronic
devices that give this system its power," Fischbach said. "It's meant to be
small, cheap and eventually built into laptops, personal digital assistants
and cell phones."

The system was developed by Andrew Longman, a consulting instrumentation
scientist. Longman developed the software for the system and then worked
with Purdue researchers to integrate the software with radiation detectors
and cell phones. Cellular data air time was provided by AT&T.

The research has been funded by the Indiana Department of Transportation
through the Joint Transportation Research Program and School of Civil
Engineering at Purdue.

"The likely targets of a potential terrorist attack would be big cities with
concentrated populations, and a system like this would make it very
difficult for someone to go undetected with a radiological dirty bomb in
such an area," said Longman, who also is Purdue alumnus. "The more people
are walking around with cell phones and PDAs, the easier it would be to
detect and catch the perpetrator. We are asking the public to push for

Tiny solid-state radiation sensors are commercially available. The detection
system would require additional circuitry and would not add significant bulk
to portable electronic products, Fischbach said.

The technology is unlike any other system, particularly because the software
can work with a variety of sensor types, he said.

"Cell phones today also function as Internet computers that can report their
locations and data to their towers in real time," Fischbach said. "So this
system would use the same process to send an extra signal to a home station.
The software can uncover information from this data and evaluate the levels
of radiation."

The researchers tested the system in November, demonstrating that it is
capable of detecting a weak radiation source 15 feet from the sensors.

"We set up a test source on campus, and people randomly walked around
carrying these detectors," Jenkins said. "The test was extremely safe
because we used a very weak, sealed radiation source, and we went through
all of the necessary approval processes required for radiological safety.
This was a source much weaker than you would see with a radiological dirty

Officials from the Indiana Department of Transportation participated in the

"The threat from a radiological dirty bomb is significant, especially in
metropolitan areas that have dense populations," said Barry Partridge,
director of INDOT's Division of Research and Development.

Long before the sensors would detect significant radiation, the system would
send data to a receiving center.

"The sensors don't really perform the detection task individually,"
Fischbach said. "The collective action of the sensors, combined with the
software analysis, detects the source. The system would transmit signals to
a data center, and the data center would transmit information to authorities
without alerting the person carrying the phone. Say a car is transporting
radioactive material for a bomb, and that car is driving down Meridian
Street in Indianapolis or Fifth Avenue in New York. As the car passes
people, their cell phones individually would send signals to a command
center, allowing authorities to track the source."

The signal grows weaker with increasing distance from the source, and the
software is able to use the data from many cell phones to pinpoint the
location of the radiation source.

"So the system would know that you were getting closer or farther from
something hot," Jenkins said. "If I had handled radioactive material and you
were sitting near me at a restaurant, this system would be sensitive enough
to detect the residue. "

The Purdue Research Foundation owns patents associated with the technology
licensed through the Office of Technology Commercialization.

In addition to detecting radiological dirty bombs designed to scatter
hazardous radioactive materials over an area, the system also could be used
to detect nuclear weapons, which create a nuclear chain reaction that causes
a powerful explosion. The system also could be used to detect spills of
radioactive materials.

"It's impossible to completely shield a weapon's radioactive material
without making the device too heavy to transport," Jenkins said.

The system could be trained to ignore known radiation sources, such as
hospitals, and radiation from certain common items, such as bananas, which
contain a radioactive isotope of potassium.

"The radiological dirty bomb or a suitcase nuclear weapon is going to give
off higher levels of radiation than those background sources," Fischbach
said. "The system would be sensitive enough to detect these tiny levels of
radiation, but it would be smart enough to discern which sources posed
potential threats and which are harmless."

The team is working with Karen White, senior technology manager at the
Purdue Research Foundation, to commercialize the system. For more
information on licensing the cell phone sensor technology, contact White at
(765) 494-2609, kfwhite at prf.org.

Louie Cueva

Thomas Gray & Associates, Inc.
1205 West Barkley Avenue, Orange, CA 92868
P: 714.997.8090
F: 714.997.3561
E: louie at tgainc.com

-----Original Message-----
From: radsafe-bounces at radlab.nl [mailto:radsafe-bounces at radlab.nl] On Behalf
Of Franz Schönhofer
Sent: Thursday, January 31, 2008 3:43 PM
To: 'Doug Aitken'; 'Brennan, Mike (DOH)'; radsafe at radlab.nl
Subject: AW: [ RadSafe ] Cell phone automatic radiation detection.

Doug and RADSAFErs,

I am happy that the word "paranoia" which I was the first to use on this
thread and which I expected to arouse protests, shows up quite frequently,
used by US citizens.....

Anybody among RADSAFErs, who can enlighten me, how radiation is measured by
a cellular phone? I have not read anything about it in the manual of my
(old) mobile phone - is it a secret code which has to be keyed in? Hopefully
the units can be changed from rem to Sv?

Best regards,


Franz Schoenhofer, PhD
MinRat i.R.
Habicherg. 31/7
A-1160 Wien/Vienna

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