Note: though the DKL LifeGuard saga is over, I'm leaving these pages up for those who may have to investigate similar quack devices. Click here to go to the latest information. Click below to go to the various sections:
Click for various Sidelines:
The DKL LifeGuard devices were supposed to be able to detect a human heartbeat, by special filtering of the dielectric potential from the human heartbeat, and this filtering was supposed to be good enough to discriminate, at a distance, and through objects, a live human from a dead human, a live ape, or a live dog. Sounds good, doesn't it? And though there is indeed theoretical justification for trying to do this, the engineering obstacles are impressive indeed. I was initially very excited when I heard about the LifeGuard.
Yes, there are theoretical reasons to suspect one could actually detect the "signature" of a human hearbeat at a distance. However, this as soon as you see one, the DKL LifeGuard immediately strains ones' credulity. They said that the tiny, tiny dielectric force from the heart is supposed to be amplified inside the device, and then to make the device actually swivel on its bearings when you hold it balanced on its handle. Somehow this tiny, tiny dielectric force was supposed to be coupled to the earth's magnetic field, or the "aether" or something. (When I asked about this during a demonstration, Mr. Sidman told me there is no servo motor or anything to move the device, and explained that it responds passively to the imposed dielectric force). And this force is supposedly sufficiently strong that it overcomes the force of gravity, which tended to make the device swivel when you tilt it just a bit.
DKL said: DKL's new line of LifeGuard instruments can locate and track any living human being more than 500 yards away in the open and at shorter distances through concrete walls, steel bulkheads, heavy foliage, earthworks, or up to 10 feet of water. All three LifeGuard models can detect and lock onto a person in three to five seconds, and they can distinguish a human from any other animal, even a gorilla or an orangutan. There is indeed evidence that DKL's devices could detect electrostatic fields, showing on an indicator light, at least on the later models. (See below for more on this.) But their electrostatic technology had nothing to do with:
1. detecting the unique dielectric signature of the human heart,
2. causing a handheld device to swivel in response to the dielectric signature of the human heart, or
3. detecting live human beings when they don't have a big electrostatic charge, or over the long distances or through the obstacles that they've claimed.
DKL labs provided no explanation of how this tiny human heart "signature," detected by a dielectric receiver, manages to "grab ahold" of this device and make it swivel against the force of gravity.
And rather than discussing this interesting but unproven technology in scientific forums, DKL was selling these devices and recommending that they be used to save lives. (Controversial claims in a research setting is one thing, in sales of lifesaving equipment, another.)
Well, I was supicious to begin with, as were the other engineers and physicists and just plain good thinkers in our search and rescue organization (the Appalachian Search and Rescue Conference), when we saw a demonstration at one of our meetings in February of 1998. I even tried one of the devices myself, trying to locate a friend standing in front of me, and it did absolutely nothing, unless I tilted it slightly, in which case I could get it to point any way I wanted. DKL says that you need hours and hours of training to make it work. That suggested to us that maybe you need hours and hours to convince yourself that it's working even when it's not; sort of a brainwashing experience.
What if DKL marketed their devices as just electrostatic field detectors, tested them for such applications, renounced their claims to distinguish human from animal hearts, renounced claims that the devices swivel in response to the unique dielectric signature of a human heart, and renounced claims for excessive sensitivity and specificity, claiming only what was shown by double-blind tests including both the Sandia and Advanced Materials Technology? Then we wouldn't have complained.
As long as it's still up, you can reach the DKL Web page and see their statements, and a report of the electrostatic testing by Advanced Materials Technology, here.
Well, we (a group of technically savvy SAR types) finally decided it was a fraud, even if an unconscious one. We were not sure if those marketing the device had been misled, perhaps by the ideomotor effect (what makes Ouija board pendulums and dowsing rods seem to move of their own accord, even though it's just due to minute movements of your hands). I offered to contact the FBI, which I did in April 1998. You can read the original letter to the FBI here.
Originally, I'd been quiet about our suspicions. We were even talking about running our own test of the devices, and I had discussed this with FBI. But then, I found out about the Department of Energy Sandia Labs tests, which I investigated in detail. These were indeed rigorous scientific tests, carried out with the prior approval of DKL labs, and the information is in the public domain. A press release from Sandia is available at http://www.sandia.gov/media/hudet.htm and the detailed test report is available at http://infoserve.sandia.gov/sand_doc/1998/980977.pdf. People can make their own judgment of the scientific validity and conclusive nature of this Sandia test. Based on this information, and the risk of death to members of the public, as a physician and search and rescue volunteer with some small reputation in the field, I felt morally and ethically obligated to inform the SAR community about my suspicions and conclusions, regardless of the legal risk to myself.
A U.S. Army Research Lab researcher had also investigated the DKL Lifeguard devices -- and in May 1998, tried to complete an even more comprehensive test of the devices at Ft. Benning, GA -- but DKL backed out at the last minute. I'd also heard of tests by other government agencies, though not available publicly, which confirmed the Sandia tests -- these other tests suggested that DKL had devices (not the LifeGuards that we were shown and that are being marketed) that could detect the electrostatic charge of a body (but not the unique varying dieletric potential of the human heart). But such electrostatic devices don't have very good range, and can't distinguish between a human and another large animal.
On an earlier version of this page, I had other things to say such as that the DKL devices "which are an expensive fraud perpetrated, (wittingly, unwittingly, or a combination thereof), on the SAR, EMS, fire-rescue, and law-enforcement communities. I originally was quiet about my suspicions, but now that the LifeGuard devices have "flunked" a double-blind test at the Department of Energy's Sandia Labs, priority goes to protecting the public from attempts to use these devices instead of proven technologies such as air-scenting dogs and listening devices. I am still very concerned about the risk to public from devices like these (there have been multiple attempts to market similar "techno-dowsers" over the years), but the more I heard from "true believers" of the DKL LifeGuards the more I suspected that much of their support was unwitting, and not a simple attempt to bilk the SAR and law enforcement communities. Nonetheless, "true believers" in treatments such as Laetrile, and devices such as the LifeGuards, can cause public harm (see the quote at the head of this page). Even though I have no personal animus against them, my moral beliefs and ethical considerations mandated that I speak out.
A friend forwarded this to me to post: a great instructive fable in Carl Sagan's The Demon-Haunted World. It's from The Ethics of Belief by William Clifford, written in 1874:
"A shipowner was about to send to sea an emigrant ship. He knew that she was old, and not overwell built at first; that she had seen many seas and climes, and often needed repairs. Doubts had been suggested to him that possibly she was not seaworthy. These doubts preyed upon his mind, and made him unhappy; he thought that perhaps he ought to have her thoroughly overhauled and refitted, even though this should put him to great expense. Before the ship sailed, however, he succeeded in overcoming these melancholy reflections. He said to himself that she had gone safely through so many voyages and weathered so many storms, that it was idle to suppose that she would not come safely home from this trip also. He would put his trust in Providence, which could hardly fail to protect all these unhappy families that were leaving their fatherland to seek for better times elsewhere. He would dismiss from his mind all ungenerous suspicions about the honesty of builders and contractors. In such ways he acquired a sincere and comfortable conviction that his vessel was thoroughly safe and seaworthy; he watched her departure with a light heart, and benevolent wishes for the success of the exiles in their strange new home that was to be; and he got his insurance money when she went down in mid-ocean and told no tales.
"What shall we say of him? Surely this, that he was verily guilty of the death of those men. It is admitted that he did sincerely believe in the soundness of his ship; but the sincerity of his conviction can in nowise help him, because he had no right to believe on such evidence as was before him. He had acquired his belief not by honestly earning it in patient investigation, but by stifling his doubts."
Sagan's book is a touchstone for those who believe in critical thinking. Highly recommended.
I have recently been contacted by a proponent of this device, with offers of information that would change my mind-- but except for anecdotal testimonials about being able to "feel" the tug on these devices when they operate, and pointers to the research on the DKL web site (see above). I have received nothing in the way of either theoretical justification for how such a tiny force can be used to generate a torque on these devices, nor any valid scientific evidence that the devices can be empirically demonstrated to function as claimed. Because I won't believe anecdotal evidence, or try the device myself in an uncontrolled fashion so I, too, will "feel the force" and become a convert, our correspondence has stopped. I will state that these contacts have fairly strongly convinced me of the following. Some proponents of the DKL devices may have been misled, but are not deliberately trying to convince others of something that they know is false. (Whether even "true believers" should be absolved from taking others' money for devices that in truth don't work, is another matter, and a difficult one with no clear answer.)
In view of the letter from the DKL lawyers, (see below), I thought that my email correspondence with one of the DKL proponents would best be aired in public. I must state that the correspondent seems to be an honorable person, acting according to his best understanding about the devices. But he just doesn't seem to understand my objections to uncontrolled testing and anecdotal evidence, and my insistence on scientific evidence seems to him to be unreasonable stubbornness. Whereas to me, I'm just trying to be scientific, as it's the best way to resolve such differences of opinion. Click here for the email exchange.
Letter from DKL's lawyers.
My reply from January 1999 is found below; click here to go down to that section.
August 24: Special Agent Denise Conrad of the FBI Washington Field Office tells me that Assistant U.S. Attorney Blanche Bruce has recommended that the FBI refer the case to the Federal Trade Commission; Michael Dershowitz is handling this for the FTC.
August 25: James Randi is a noted skeptic and debunker of fraudulent claims of paranormal abilities (such as "spoon bending" by psychic force), and in recent years emerged as a mostly self-taught but scienfically-respected skeptical spokesman. (There is a good parallel with Martin Gardner of Scientific American fame.) His James Randi Educational Foundation has a standing offer of $1,000,000 to anybody who can demonstrate scienfic proof of a paranormal occurrence. As a stage magician, Randi has the expertise (lacked by many less-worldly scientific researchers) to control strongly against ingenious means of cheating. I hear that Mr. Bryant, who is a proponent of the DKL devices and is convinced that it works not just as an electrostatic detector, but will swivel in reponse to human hearts at a distance, and only to human hearts, plans to apply for this prize using the DKL detector. My email correspondence with Mr. Bryant can be found here.
August 26: A researcher who is familiar with the DKL
devices, but who prefers to remain anonymous, says the following:
That circuit that performs the electrostatic charge perturbation sensing has always been part of the devices. On the earlier models this has performed the function of driving the red LED on the back of the unit. The indicator light was supposed to help the user discriminate between real and imagined detections of the DEP (dielectrophoresis) part of the device. The two distinctly different parts of the device are connected at only one point, they are both connected to the same anetnna. DKL has often presented this as "proof" that the device works as a whole using inductive reasoning that because this part of the device works, the entire device works. This aspect of the device was demonstrated during testing but was dismissed as not being part of the testing because even DKL boasts that the electrostatic charge perturbation (ECP) sensor need not be active (not even powered) for the so called DEP portion to function. They have never claimed that the ECP sensor was responsible for the swing-and-point function. Even Joseph Dougherty (the Penn State resercher) was careful to state that his tests were related ONLY to the ECP functionality.
The LA Times had an excellent article about the devices in the September 24, 1998 issue. Although it has expired from their Web pages, here is the title and first and last sections to give you the flavor and aid you in finding it; you can get a copy from your local library, or check the LA Times archives (though for a small fee) to get an electronic copy.
Thursday, September 24, 1998
A Detector With Detractors Manufacturer of device, which has been used by an L.A. police group, says it can help locate fugitives or victims buried in rubble. But some scientists call it a fake. By THOMAS H. M AUGH II, Times Medical Writer
What do techno-novelist Tom Clancy and some segments of the Los Angeles police
have in common? Both have praised the merits of a "human-detecting" device that critics charge is an outright fake. Clancy used it in his newest novel, and a Los Angeles narcotics task force says it has been 100% successful in using the device.
LifeGuard, manufactured by DielectroKinetic Laboratories, LLC, of Washington, is marketed as a device to detect the faint electrical signal of a human heartbeat--at distances of up to 500 feet, and through metal, concrete and water. The company says the device, which comes in three models costing $6,000 to $14,000, can pinpoint victims in the rubble of a demolished building or locate criminals eluding police. "People can be localized through concrete and steel walls, earthen barriers, inside stationary or moving vehicles and underwater," the company's literature says. "There are no known electronic or other countermeasures." A federal laboratory that tested the device to determine if the government should purchase it, however, found that its success rate in locating hidden individuals was little better than would be predicted by chance. The company says its own tests are much more successful and that the government tests were flawed.
. . .
Police Group Backs Claims One person who agrees with the company about the value of LifeGuard is Lt. John Montanio of the Los Angeles Interagency Metropolitan Police Apprehension Crime Task Force, or LA IMPACT, a low-profile police group focusing on major narcotics traffickers. Montanio says the group has four of the devices and is the only police agency in the country to use them tactically. "It's been 100% effective for us," he said, although its use has been appropriate only in a small number of cases. In one case, a month ago, LifeGuard helped find a suspect in a large warehouse, he said. In a second, involving a hostage situation in Industry, LifeGuard showed where hostages were being held inside a house, but also indicated a human presence at another corner of the building. "I thought it was a mistake, but we later found out there was a baby there," he said. Montanio is aware of the criticisms, but says the device has proved itself. "One positive hit I can understand as a coincidence, but we are seeing too many 'coincidences' " for it to be a fake, he said. The National Institute of Justice may organize further tests of the device. But until such tests are conducted, Shermer said, potential purchasers should heed the advice of skeptics: "If something appears to be too good to be true, it probably is." Product information about LifeGuard can be found at the company's Web site: http://www.dklabs.com
* * *
Does It Work? LifeGuard's makers say it can be used to locate humans in collapsedbuildings or to detect fugitives who have evaded police pursuit. TomClancy featured it in his new book, 1/2Rainbow Six. Serves as visual guide for operator. Frictionless bearing: mount allows device to point at subject. Dielectric field: company scientists say it can detect a faint dielectric field producedby a human heart, even through concrete, steel or water. Some scientists question this claim. LifeGuard Model 2 Eye-safelaser pointer Telescoping antenna sections Data port LightPower switch for amplification circuitry Frictionless bearing mount BatterySource: Dielectro Kinetic Laboratories
Copyright 1998 Los Angeles Times. All Rights Reserved
Search the archives of the Los Angeles Times for similar stories about: DIELECTROKINETIC LABORATORIES LLC, DETECTION DEVICES, POLICE EQUIPMENT, TECHNOLOGY, FRAUD. You will not be charged to look for stories, only to retrieve one.
I have heard from some who have tested the DKL devices that they may have some sort of electrostatic detector in them -- and on the DKL web page is a statement of a test, run by Advanced Materials Technologies of State College, PA, which seems to show that they can detect a human body behind a wall -- but this test is clearly different than how the devices are supposed to be used to locate live human bodies (see the letter to the FBI for an explanation of how the devices are supposed to work). Therefore, even if this test did have results as stated (and the author of this study is reputable, and I have no reason to doubt him), it is in no way support for the claims for the device, made to me and to others, about how it will swivel with a torque from an amplified dielectric potential from a nearby live human heart.
It does seem, from my conversations with various researchers, that DKL's devices function well as a detector of moving static charges, such as a person walking across a carpet -- and can detect such a person through walls. But, does this mean it can detect a bruised and bleeding body beneath a collapsed building? No. Does this mean that it can discriminate a human heartbeat from a cat that you've rubbed, or even a comb that's been run through your hair? No. Does it mean that it can discriminate a human heartbeat from a dog's? No. Does it mean that there is enough force from the dielectrophoretic force to swivel a heavy device held in your hand? No.
But, since a quasi-static electrostatic near-field can be detected with a short field probe, the short "antenna" on the LifeGuards can really function as an electrostatic field probe, and should be adequate for detecting a slowly-moving electrostatic charge. Thus, the objection (that I had voiced in my letter to the FBI) that the antenna is too short doesn't hold water -- as long as the device is used as an electrostatic field detector, not a dielectrophoretic heartbeat detector where a human hearbeat, and only a human hearbeat, will make a handheld device swivel and point to the person.
It sounds as though DKL may have developed a good static-field detector, though that's
not not what they're claiming. Static-field detection is a fascinating field, and if DKL
has developed good filtering, as some of the researchers with whom I've talked believe,
they may have a good technology that is saleable. If you're interested in such
matters, here is a link to a study on the topic:
Another paper on the topic is Hull, David M., and Steven Vinci. Passive Detection and Noncooperative Target Identification of Helicopters Using Extremely Low Frequency (ELF) Electric Field Sensor. 1998 Army Science Conference Proceedings, June 15-17, 1998. I'm afraid this one is not available on the Web yet.
The DKL page also has a posting of an "executive summary" of a test by the LAW Group, but it provides no technical details of the test, and therefore until they post details, it's really just a piece of marketing fluff. In correspondence with proponents I have suggested that they post the details of the test so the public can compare with the Sandia test.
On August 23, 1998, I received a threatening letter from the DKL lawyers. (Interestingly, they didn't send the letter registered or certified -- seems unusual if you're really considering a civil suit.) Well, they haven't sued me yet, as threatened, and I still maintain the truth of the analysis posted here. Indeed, I consulted with my lawyer and on January 16, 1999, sent a detailed reply to the points of their lawyer's letter. It is available in Adobe Acrobat PDF format, or in HTML. I have received no communication from DKL since then. Important points from discussions with my lawyer:
The threat of defamation actions is often used as a threat to silence public debate. Indeed, such suits are called "SLAPP" suits (Strategic Litigation against Public Participation), and you can find more information about SLAPP suits here.
There are defenses against defamation: "truth is an absolute defense against defamation" is the standard legal saying, but there are limits on this, so don't depend solely on truth as protection if you decide to speak out. And if you can, point to the objective aspects of the truth you claim. In the case of DKL, we have excellent tests by Sandia Labs -- and you'll note my letter is careful to reference these as the source of this truth.
And be careful of what you say -- for instance, one potential critique of the DKL LifeGuard is that the antenna is too short to "work" at the radio frequencies of the human heart. But if it's not working as an antenna but as an electrical field probe -- it's plenty long enough.
Publications such as newspapers have a certain amount of protection against defamation, and so a Web page such as this may have some protection, protection that might not apply to letters, email messages, or public statements. But it'll take a while for the courts to rule on this and let us know for sure whether this press protection applies to Web pages.
There is also protection against defamation when speaking about well-known public figures -- and these can be well-known only in a specific community, and there is a good argument that DKL, by dint of its many public pronouncements and demonstrations, has made itself a public figure in the SAR community.
Finally, there is protection against defamation for those involved in scientific debate. If you look carefully at my letter, you'll see where I've crafted my reply in light of this -- talking in particular about "sound theoretical basis" in particular.
Sigh. I truly would prefer to ignore most quackery -- but I think that physicians, SAR people, and for that matter, the educated public in general, have an obligation to speak out when the public is in danger from either fraudulent or simply misguided technology. I hope the above helps you if you decide to speak out.
The National Institute of Justice's National Law Enforcement and Corrections Technology Center commissioned a detailed study of the DKL Lifeguard devices in October 1998, and the results are now (February 1999) available on the Web. The scope of the examination leaves no doubt as to the conclusions, and the details are fascinating.
The "circuitry" of the supposed dielectric detector is a sham -- it is a simple electronic LRC (inductor-resistor-capacitor) circuit on a breadboard. However, it can't even function as an electronic circuit -- it's an open circuit! And if anyone says that it's just there for window-dressing in case someone who buys one looks inside and expects to see some electronic circuitry, I beg to differ -- look at the pictures in the DOJ report, it's an ugly piece of work! And any ham (radio amateur) could look at it and see it couldn't work. Interestingly, although there are a couple of pieces of dielectric material sandwiched into this nonfunctional LRC circuit, the LRC is not a dielectric circuit or detector, even in terms of all the fluff and references DKL puts out! But some have suggested that the DOJ report misses the whole point: in between the two little pieces of dielectric material, guess what DKL put in there, sandwiched between two pieces of dielectric material, to (supposedly) make the device sensitive to the human heart but not other species or dead humans:
a hank of human hair! (See the DOJ report for details of where in the circuit this was found.)
These people say (and I tend to agree with them, though of course it's never possible to truly know what other people really think when they're building) that the LCR circuit doesn't need to work as an electronic or dielectric circuit -- it's all just part of the structure needed to support what is really a sympathetic magic spell (similar to sticking pins in a doll of someone, with bits of hair and nail clippings in it, to hurt them). But as the previous Sandia report proved, this particular spell works no better than random guessing. Maybe the incantation was off. Or maybe it needs to be a piece of human heart between the two pieces of dielectric material? <eg> Or, as my wife observed, they simply didn't understand sympathetic magic -- you need a piece of that particular person's hair to make it work.
My hats off to the others, particularly those at a particular Board meeting of the Appalachian Search and Rescue Conference, who were able to arrive at the same conclusions independently. It bespeaks the value of a broad liberal arts education, I think. Thanks also to all the various researchers who networked (mostly via the Internet!) to expose this. I won't mention any names here unless you (and you know who you are) send me an email and let me know that it's now OK to do so.
In addition to the DKL web page, there are several other pages with information about the devices:
1. Bob Caroll's well-known Skeptic's pages have an excellent section devoted to the LifeGuards.
2. An anonymous author who had some close encounters with the devices has put up a set of pages with some detailed information about the DKL LifeGuards and similar devices. Great background. Although I'm against anonymous publications on general principles, after the threatening letter from DKL, I can see why the author chooses to remain anonymous for now.
3. Robert Park, a spokesman for the American Physical Society, has posted a brief comment on the devices on the APS Web page.
Actually, the best end to this sentence I've heard is ". . . are condemned to repeat fourth grade history class" but seriously, devices like the LifeGuard have been popping up and disappearing on a regular basis. The Quadro was a device that looked almost the same, and worked (or rather, didn't work) almost the same, as the DKL LifeGuard. It was marketed for a while, until the principals ended up in court. Here are some links that tell the story of the Quadro:
I don't think there is 100% certainty about anything (except perhaps for religous convictions). We may be "99 with a thousand 9's after the decimal point" certain about many things, and that's what we have to use in order to go on with our lives. At this point, I'm bout 99.99% sure that the DKL LifeGuard devices don't work as DKL labs claims. [Sideline -- Some skeptics use ad hominem attacks, personal denigration, and try to make fun of those they don't believe. I think such attacks are a form of hubris, demean those who employ them, and intend to avoid such statements. I'll try to be as objective as I can.]
As T.S. Kuhn writes so convincingly in The Structure of Scientific Revolutions, the most interesting scientific questions are those that lie outside the current paradigm of a given field, as they are most likely to produce a new paradigm. On the other hand, there are so many crank claims out there that one can't possibly investigate them all -- as someone once said "You need an open mind, but not so open your brains fall out." Since there are zillions of extraordinary claims that may clamor for ones' attention, how do you figure out which ones are worth investigating more deeply? Theory and current paradigms are a good first test. If a device seems to defy current scientific and engineering knowledge, it's probably not worth investigating unless there is adequate empirical evidence for it working. Anecdotes are not scientific evidence. Those who have experienced something that seems to work for them (that's anecdote), before telling others that the device works, should do some objective testing to make sure they haven't fooled themselves. They need to use controls to make sure their results aren't being swayed by unconscious bias. And, they should make sure that these tests are conducted in a way that others are assured there is no fraud involved. (Remember, we're trying to convince people of an extraordinary claim, the proof needs to be bombproof.) There are several ways to design testing controls to avoid bias, and to assure others there has been no fraud. Since nowhere else in research are we so likely to fool ourselves as in medical research, medical researchers have come up with something called a "randomized, double-blind placebo-controlled trial." This model is a great starting place for extraordinary claims in other fields as well, because it is so carefully controlled for bias. Here are a few links to Web resources about the principles of research:
And, for a guide to evaluating research papers, and tests of equipment, check out the following series. Though designed for medical readers, the type of research techniques needed for devices such as the DKL devices are similar. And this series includes wonderful topics such as "Statistics for the non-statistician. II: "Significant" relations and their pitfalls."
For articles about the difficulties of formally comparing tests with different results, and how to do this scientifically (called meta-analysis-- what one will have to do for the DKL devices if there are conflicting test results), see:
I surely wouldn't spend all this time and effort trying to debunk "therapeutic touch" or theosophy. Why pick on DKL? Well, with the DKL claims, they directly bear on one of my areas of interest and some expertise -- search and rescue. And, there appears to be a signficant danger to the public safety. The combination of these two factors got the attention of me and some of my friends.
What would it take to convince me that I'm wrong about the LifeGuards? Well, I'd consider DKL's claims extraordinary, so I'd want to see extraordinary proof to overcome the solid scientific negative results of the Sandia tests.
First, I'd like to have some theoretical justification that a dielectrokinetic force can swivel a half-pound device that you hold in your hands. All I've heard or seen so far is handwaving about the dielectric equations. But hey, this is an engineering question -- how do you get the force to make the thing to swivel in your hand?
Second would be empirical tests, preferably paid for by someone else other than DKL labs, and controlled for possible fraud by someone with expertise in this area (James Randi, for example), using the roughly the same test scenario as used by Sandia. Neither of the tests posted on the DKL site comes close. Reportedly, DKL labs has accused Sandia labs of bias (or fraud) against DKL labs because Martin Marietta both runs Sandia labs for the Department of Energy and has developed a "competing" device using listening technology to detect the sound of a human heartbeat through lots of noise. For example, you can reportedly attach it to cars or trucks leaving a prison and tell if there's someone hidden inside. It's called AVIAN and I don't know much more about it than that. However, even if AVIAN works as described -- and at this point I have no reason to doubt it as I have strong reasons to doubt the DKL lifeguard devices -- it will be, as far as I can tell, of no use to wilderness search and rescue, so I'm not particularly interested. I guess I should also say that I have no connection with Martin Marietta, Sandia Labs, the Army, or anyone marketing any device that is "competition" for the DKL. And, as you can tell from these pages, I'm no technological Luddite -- I like high-tech devices. I just don't think that the DKL lifeguard devices have adequate theoretical basis for their operation, nor any empirical evidence for their effectiveness in the claimed settings (telling live humans from dogs from an inanimate object with a big static charge). And my interest in the skeptical movement (see the Links page for more) led me to understand how anecdotal evidence isn't really evidence, how we and maybe the purveyors of devices such as the DKL LifeGuard devices can be misled by what skeptical investigator James Randi terms the ideomotor effect (see the letter linked at the beginning of this paragraph for details).
Now, a definitive study shows that the LifeGuard devices cannot possibly work as claimed. And, since there can be no more scientific controversy about it not functioning as claimed, and the danger to the SAR community is averted, I think I'm starting to lose interest (yawn). There will probably be more to the story -- exposÚs in the press, maybe criminal trials. But I'll leave that to others like Bob Carroll and James Randi to tell.