Cell Phone Radiation Detectors Proposed to Protect Against Nukes

crosshatch brings us news out of Purdue University, where researchers are developing a radiation detection system that would rely on sensors within cell phones to locate and track potentially hazardous material. From the Purdue news service: "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. '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. 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.'"

Re:Bad Idea

[El Yanqui]

You weren't paying attention. Many cities have already placed a network of microphones that can detect gunfire. Through triangulation police are able to determine where the shots came from.

Here's one link of many you can find through Google. http://www.wired.com/science/discoveries/news/2004/11/65802 [wired.com]

Re:And for those with Prostrate/thyroid cancer?

[RDW]

This kind of thing is already happening with existing anti-terrorist radiation detectors, e.g.:

http://www.schneier.com/blog/archives/2005/03/nuclear_terrori.html [schneier.com]

http://findarticles.com/p/articles/mi_qn4176/is_20041221/ai_n14588366 [findarticles.com]

http://environment.newscientist.com/article/dn3150 [newscientist.com]

Hate to nitpick, but ...

[Ihlosi]

MRI machines (and for that matter healthcare in general)

While there are lots of diagnostic and therapeutic procedures that involve radioactivity of some sort, MRI is not one of them.

Tracking politicians

[TooTechy]

Bush: Would someone please design a device to be able to track Senator Clinton's whereabouts in the forthcoming campaign?

Politicians have been followed for ever to find out who they are seeing before an election. This is just another way of being able to follow th right people at the right time. Does it have anything to do with us? No. Not until you become the right person.

A little revolution now and again is a good thing. Not possible if everyone knows where you are.

Paranoia, certainly. But not whithout good cause.

"Nothing to fear folks, we just want to turn up the sensitivity in the devices for a few weeks for an experiment. No reason to be alarmed"

False triggers deliver sensor number and location. We found Clinton!

Re:False Positives

[mpe]

Not necessarily... Radiation isn't a single monolithic thing. A massive dirty bomb made out of an alpha emitted wrapped in lead to stop secondaries will be almost undetectable by a device buried inside the nice plastic case of a mobile phone.

You only need lead if whatever you are using is a gamma emitter. Both alpha and beta radiation is stopped by "tinfoil". A phone case painted with metal paint would probably be all the shielding you'd need.

If you have a system like this running, the hypothetical bad guys will know about it and will take action to prevent detection.

Or set off something fairly harmless which will trigger the detectors and cause a panic.

Re:Hate to nitpick again, but ...

[ttapper04]

1. Thank you for the correcting the spelling mistake.

2. I'm glad you brought this up, radioactive materials do not release Sieverts. They do release Beta partials, Alpha partials, Gamma radiation and other fission fragments.

You are also correct in pointing out that a Sievert usually refers to the amount of damage done to a single gram of your body by these partials. If evey gram in your body is exposed to 1 Sievert, then it is correct to say you received a "whole body dose" of 1 Sievert. Furthermore if 25 people each receive 1 Sievert (whole body) then the population is said to have received 25 Sieverts. The linear Hypothesis states that for every 25 Sieverts in a population there will be one cancer death (in addition to the 20% given mortality rate of cancer). Forgive me for not clarifying at first.
Your numbers are a little off but you have the right idea, a 25 Sievert dose will kill one man in less then an hour; in fact 25 Sieverts is more then sufficient to kill several people. Exposure to 3 Sieverts is commonly referred to as "LD50", giving the person a 50% chance of dieing. People rarely survive a whole body dose of 10 Sieverts. The linear hypothesis does not apply when the dose is large enough to kill from radiation sickness.