Can Imaging Technologies Save Us From Terrorists?

itwbennett writes "In the aftermath of the failed Christmas Day terrorist attack, full body scanning technologies such as millimeter wave and backscatter are regaining popularity, writes blogger Steven J. Vaughan-Nichols in a recent post. But, he asks, do they really work? The TSA seems to think so. It has just issued a contract to purchase more millimeter wave scanners from L3 Communications. Michael Chertoff, the former homeland security secretary, told the New York Times that if these scanners had been in place, they would have caught the would-be bomber. Ben Wallace, the Conservative Member of Parliament in the United Kingdom, disagrees, saying that the technologies can't detect the kind of low-density explosive that the would-be terrorist tried to use on December 25th."

Comments

wha

[poetmatt]

aren't these the scanners known to have health risks and/or not work?

Re:wha

[ILikeRed]

This is a better link to information on the damage to DNA from Terahertz scanners. It was covered in Slashdot earlier, don't know why it is not a related story.

Quoting the earlier story:
"Now a team led by Los Alamos National Labs thinks it knows why. They say that although the forces that terahertz waves exert on double-stranded DNA are tiny, in certain circumstances resonant effects can unzip the DNA strands, tearing them apart. This creates bubbles in the strands that can significantly interfere with processes such as gene expression and DNA replication. With terahertz scanners already appearing in airports and hospitals, the question that now urgently needs answering is what level of exposure is safe."

Kiddie Porn Laws Defeat Scanners

[scorp1us]

There was an article that mentioned that use of these scanners violated GB laws on child porn. So now you have kids (up to 17) - very impressionable and angsty kids - that will become the target of recruitment by terrorist organizations. Epic FAIL.

What we need to do now is to accept that airline travel is not safe, and can never be safe. Everything in life that has the best rewards also has the greatest risks. Why can't we just factor risk into airline travel for the reward of being a timezone away in an hour? I would still fly. And those who wouldn't would push for a transcontinental high-speed train (Mag-Lev?) which would have a lower risk/reward, but just as cost effective.

   

They are another layer

[Anonymous Coward]

Disclaimer: I am an expert in millimeter-wave and terahertz imaging technology, both passive and active. I have posted here many times before, also as AC, for obvious reasons.

The short answer is a qualified YES. All imaging technologies can (help) save us from (some) terrorists. Specifically, those individuals carrying dangerous/unknown objects or materials outside their body, whether integrated with their clothes or simply bound to their body. The proof is in the images. I will provide examples if asked.

As far as safety concerns, the active millimeter-wave systems are safer than your cell phone or laptop wifi. The x-ray backscatter systems give you a dose of radiation that is far less than what you receive while flying over a few states at 39,000'.

The ultimate issue for most people is privacy. I won't get into that here; I just know the phenomenology and implementation side. I will answer any questions now, so please respond.

Re:They are another layer

[girlintraining]

The ultimate issue for most people is privacy. I won't get into that here; I just know the phenomenology and implementation side. I will answer any questions now, so please respond.

Safety interlock design -- is the operator capable of increasing the radiation dosage, and if so what interlocks are present to prevent the person being scanned from being exposed multiple times or at a higher level than intended? The medical field learned from the therac-25 incident, but this is an airport scanner, not a medical scanner. Are the safety standards and review process comparable? How tamper-evident is the system, and what are the possible failure modes that could endanger the operator or person being scanned? Is there a sound or visual indicator the person being scanned can hear to indicate when it is in-use or when it is being activated multiple times?

I have read these scanners are capable of covertly scanning large crowds in real-time. That implies a steady-state emission -- while a single use of this device may be quite low, what are the risks to continual exposure over, say, a 45 minute timeframe? What about frequent travelers -- at what point are the safety margins compromised?

There are statements that the device will not be enabled for the transmission/storage of images -- but while those devices may be shipped with that disabled by default, it makes no sense from an employee-training perspective not to have records and auditing in place. Is it safe to assume this is just hyperbole to reassure people and the machines can be easily configured to do this?

Why millimeter wave over other frequencies in the RF spectrum? Is this just a shortcut from a computational standpoint, or is there an advantage here that can only be realized by this technology? Why not use IR scanners? They can see through many types of clothing as well: and have the added benefit of being a lot safer.

Re:Just wait...

[fyngyrz]

Only problem is traveling intercontinentally.

Not a problem. Take a cruise ship. Loads of fun, great food, gambling, accommodations from basic to extreme luxury, swimming, tennis, dancing... I haven't been on a plane in decades and I've been to every continent except Antarctica in that time. You'd be surprised how reasonable the prices are, too, presuming you don't absolutely have to get that luxury suite. Though I highly recommend them. :)

Re:yeah, and?

[afxgrin]

Well - sounds better than the magic wand the Iraqis are using.

Even so - the millimeter wave approach would probably identify any wiring or fuses that are secondary to the explosives in the crotch. In the end though, the only real solution is full body X-ray scans.

Maybe they can offer the option to send the scan to your Doctor's office if requested. Probably catch all sorts of undiagnosed medical problems for every person who gets on a plane. You're probably going to get a similar dose on a high altitude flight anyway...

The idea of having a huge database of full body x-ray scans could be a medical researchers dream. I'd start with making a visual recognition system for tumours, pneumonia, spinal issues - the results could be pretty awesome.

X-ray densities just need to be kept really low, and with modern digital detectors, it's likely to be easily achieved.