Handhelds let first responders detect radiation

Los Alamos Lab firefighter Tracy Stidham consults a radiation spectrometer with home-grown analysis software running on a Palm i705 handheld.

When Mike Dunning, a Lawrence Livermore National Laboratory physicist, heads out to confirm reports of high radiation levels, he plugs his detector into an unlikely power source'his car's cigarette lighter.

Taking science on the road wasn't always so easy. Dunning's portable gamma ray detector prototype is a far cry from the 55-pound spectrometers and 30-liter liquid nitrogen tanks that his predecessors lugged in the field.

Equally portable is the RadScout handheld computer that accompanies the detector. The RadScout, whose five-year development cost more than $3 million, consists of a Hewlett-Packard iPaq Pocket PC H3600 handheld computer running Microsoft Windows CE and analysis software written by the lab's own programmers.

Energy Department labs had experimented with shrinking portable radiation detectors long before the Sept. 11, 2001, terrorist attacks, but since then the labs have been making the detectors and their IT components smaller, faster and simpler for first responders to use.

And if uncertainties still linger, the handheld detectors can double as communication devices for first responders to consult with far-off experts via wireless e-mail.

'It's been easier to get funding and support recently because more people recognize the issue,' Dunning said. 'Before, it wasn't much of a priority.'

On the spot

Their algorithms narrow down the search area second by second, pinpoint the isotopes emitted by a radioactive object and process the gamma ray and neutron readings. They can tell, for example, whether the object is indeed a threat or, say, merely medical isotopes used to detect cancerous cells.

The software constantly displays its algorithmic conclusions on the iPaq's screen in real time. Another piece of software manages wireless information flow between the handheld and a desktop of a distant expert, who can engage in a quick e-mail consultation that's displayed on both screens.

'It doesn't take a scientist to run this,' Dunning said, 'but there's built-in ability to send data back to us.'

Like older spectrometers, its detector crystals require low temperatures'280 degrees below zero Fahrenheit'for good detection. Unlike its predecessors, it needs only an attached 25-pound refrigerated chest, an eighth the size of bygone detectors.

That portability means answers in minutes instead of hours. 'Unless you know where [radiation] is, you're going to be walking up and down halls looking for it,' Dunning said. 'You want something you can carry with you.'

The RadScout prototype technology was licensed in June to Ortec Products, a business unit of instrument maker Ametek Inc. of Paoli, Pa., which plans to begin selling the portable detectors commercially next year. The next prototype, now under development, could slice another eight pounds from the total weight with lighter, lithium-polymer batteries.

Another device the size of a paperback book has a handheld computer attached to the front. A Los Alamos group built the first-generation prototype in 1995. By the end of this summer, 42 units will be delivered to Energy's radiation detection teams across the country.

They'll incorporate a Palm Inc. i705 handheld with a sodium iodide-based spectrometer that uses a cadmium-zinc telluride crystal. LuckyII, the in-house spectrometer software, does the same job as RadScout's: locating and deciphering radioactive isotopes. LuckyII shares its judgments with RedEye, an in-house Palm software application that displays results on the screen.

But LuckyII has a somewhat different modus operandus. Its search function sets alarms indicating certain radiation levels. In Scan mode, the software graphs the radiation levels over a period of time. In Confirm mode, the software tries to match the radioactive energy against reference levels stored in a minilibrary. The Palm screen displays that match, which can be uploaded to another computer for further scrutiny.

'You would like to filter the threatening from the innocuous' radiation levels, said William Murray, a Los Alamos project leader for the nuclear instrument. 'We do realize there are a lot of false alarms.'

The State Department's counter-nuclear proliferation efforts provided slightly more than $1 million to develop the LuckyII and RedEye systems. Murray said in the next five years, he hopes to chop in half the $20,000 manufacturing cost of each device, so that more first responders can afford the units.

Projects to minimize the detectors to more mobile levels'including another joint development project on a 10-pound Cryo3 device at Livermore, Los Alamos and Lawrence Berkeley national labs'has enabled a new kind of instant detection and correction that could save tens of millions of dollars, and ultimately lives.

'Whenever you get the wrong answer,' Murray said, 'it always costs you.'

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