Nobody expects any high-tech solution will erase America's new sense of insecurity. But there are some innovative approaches that could find a place, and particularly promising are recent advances in low-dose X-ray scanning.

A commercial "backscatter X-ray" system capable of seeing what's under a person's clothing -- including plastic weapons or explosives -- was installed in 1997 as an experiment at the Montana State Prison, a 1,300-inmate facility at Deer Lodge, Mont.

Warden Michael Mahoney says the prison is now scanning about 300 inmates twice daily as they move back and forth between work areas and their cellblocks.

"We've been very pleased with it," he said. "In this environment it's something that has worked well. It's another tool of the trade that enhances our ability to detect contraband being brought into the institution."

But it also raises privacy and health issues. At the prison, Mahoney says, inmates have complained about the potential damage of frequent X-rays, even at very low doses, and prison officials were warned to expect a lawsuit on constitutional grounds if they attempted to screen visitors to the prison.

As its name implies, backscatter X-ray technology creates an image from the radiation that is scattered back from whatever is being scanned. Both the source of the X-rays and the detector that is used to generate the image are on the same side, eliminating the need to pass radiation all the way through the object as in standard X-ray imaging.

The display highlights the edges of anything that varies in physical density from the background. In theory, a plastic knife or gun can be picked up as well as metal.

It's also been tried in some countries to thwart drug smugglers, and a version has been designed for use at border stations -- said to be capable of finding people hiding in the trunks of cars or inside trucks.

At the Montana prison, authorities have found the system to be an effective alternative to frisking felons for improvised weapons and other contraband -- including even small tools and ballpoint pens.

The same technology has been examined at the Lawrence Livermore National Laboratory and by safety experts around the country for potential use in protecting against terrorists at public facilities.

Some daunting health and privacy issues have to be worked out before it could ever be used in a domestic airport. But experts say those issues were cast in a whole new light last week.

"The cost-benefit analysis looks a little different now," said C. Kurt Zorn,

who studies aviation safety at Indiana University's School of Public and Environmental Affairs. "We may have to go back and look again at technology that at one time we thought would be too expensive or just impractical to roll out across the country."

Harry Martz, a physicist at the Lawrence Livermore lab, was part of a team of scientists that recently evaluated whether full-body X-ray scans and other high-tech security systems could play a role in domestic airports.

The verdict: Forget it.

"You see under the clothing," Martz said. "People were uncomfortable with that."

Now, he said, attitudes of the traveling public might be somewhat more open to the idea. Martz noted that displays could be rigged so that only suspicious objects -- and not someone's body outline -- is revealed.

Besides the privacy issue, however, there are also health questions that have yet to be answered.

American Science & Engineering Inc., a Massachusetts company that manufactured the "BodySearch" system used in Montana, has claimed that it would take 7,000 scans with that system for someone to be subjected to the equivalent dose of radiation received in a single standard X-ray in a doctor's office.

But radiology experts say that does not mean frequent flyers and airline staff should have nothing to be concerned about if they are facing the prospect of being forced through scanners several times a day every time they enter another airport.

"You have to be worried about the cumulative dose over time," said Robert Gould, a professor of radiology and bioengineering at the University of California at San Francisco. "You also have to be concerned about skin effects.

There is no way you can absolutely say the skin doesn't get anything, and the skin is thought to be radiosensitive."

Other potentially vulnerable body parts include the corneas of the eye and superficial organs, such as the salivary and thyroid glands. Careful studies have not been done, Gould says, and would be difficult and expensive to carry out in a way that would reassure the traveling public.

Scanned images of a man displayed on the American Science & Engineering Web site clearly show hidden weapons. But the outlines of bones in the man's legs are also visible. The model reportedly wore lead underwear for the sake of modesty.

It might be possible to lessen the X-ray exposure, but only at the price of losing some of the resolution and detail of the image, which could allow someone to smuggle a small object. Some types of plastic objects might approach the density of body parts and thus be hard to pick out. And operators would still have to be trained to spot suspicious objects and maintain their alertness through the tedium of scanning hundreds of people.

"Clearly there are going to have to be some answers before this would be acceptable," Gould said. "The physics behind it is fairly straightforward. But the implementation to get this technology to work is another matter."

Then there's the overarching philosophical question: Just how good can any technology be against a dedicated, well-financed terrorist operation?

"We all know that terrorists are smart enough to find out where the weak spots are," Zorn said. ''There are some obvious holes, and we should plug up those quickly. But if we harden one target, they will find another. We see now that people can make weapons out of things we've never thought of as weapons before."

Screening technology and airport security routines seem almost certain to tighten considerably. But safety experts say the only genuine solutions involve identifying terrorists before they strike, and ultimately eliminating the source of the hatreds that fueled last week's attack.

It's unclear whether any technology could be capable of meeting that goal.

Upgrading Airport Security

Tuesday's terrorist attacks with hijacked airliners have prompted a review of security in the nation's airports and skies, particularly of how technology can advance certain security measures. One company, Ancore Inc., is developing a scanner that can look for explosives, narcotics, alcohol or environmentally hazardous materials by detailing the chemical composition of a bag's contents.

1 - Neutron emission The cargo is bombarded by short pulses of fast neutrons that cause the contents of the luggage to emit gamma rays.

2 - Element detection Gamma detectors collect the elemental signals from the cargo and integrate that information into a high-resolution image.

3 - Computer comparison The elemental signals are compared to the material signals of different elements stored in a database. The scanner then displays the image, color-coding the display to indicate the absence or presence of a material. . Source: Ancore Inc. Associated Press Graphic.

Note: X-ray scanning reconsidered, but problematic.

Source: San Francisco Chronicle (CA)
Author: Carl T. Hall, Chronicle Science Writer
Published: Monday, September 17, 2001
Copyright: 2001 San Francisco Chronicle Page A - 11
Contact: letters@sfchronicle.com
Website: http://www.sfgate.com/chronicle/

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X-Ray Vision - Time Magazine
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Can't Scan Without a Warrant
http://cannabisnews.com/news/thread10027.shtml

High-Tech Devices Require a Warrant
http://cannabisnews.com/news/thread10026.shtml

Court Limits Police's High-Tech Search of Homes
http://cannabisnews.com/news/thread10023.shtml

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cheers................dddderanged


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dow is very close to ending down 666.

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dddd

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All we can do about that,is make sure we know God personally.
I'd hate to be the only guy who had the right kind of gas mask.You would have to take it off sooner or later to drink water,or eat.When you realised that everyone else was dead,you might have the strange,lonesome feeling of being left behind?

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This has been standard training in the military since Nam. Maybe before Nam but I do not know first hand what training was available back then. While in the military, I found it hard to believe that the gas mask, the mop suit, the booties, the chemical gloves etc. would protect me from a nuclear strike. I felt more reassured that they would protect me from bio or chemical attacks until I could get to "clean air." I am sure I am not the only nervous citizen that has not located a personal gas mask yet. You can bet congress, the military, and law enforcement have them.

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dddd

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dddd

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here are some links
http://members.tripod.com/~sporkk/
http://oak.cats.ohiou.edu/~jm703496/spork/


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dddd

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dddd

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http://www.cnn.com/2001/US/09/16/gen.hate.crimes/


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And if people think that the new powers sought by the Repression Apparatus will never be abused cause right now everyone is looking in the same direction, well, give it a year or so..

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And they want to use this on people? I'll think I'll take the trains, from now on.

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