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How Bad Can Wi-fi Be?

Zonk posted more than 6 years ago | from the good-thing-we-have-real-experts-here dept.

Wireless Networking 434

An anonymous reader writes "Sunday night in the UK, the BBC broadcast an alarmist Panorama news programme that suggested wireless networking might be damaging our health. Their evidence? Well, they admitted there wasn't any, but they made liberal use of the word 'radiation', along with scary graphics of pulsating wifi base stations. They rounded-up a handful of worried scientists, but ignored the majority of those who believe wifi is perfectly harmless. Some quotes from the BBC News website companion piece: 'The radiation Wi-Fi emits is similar to that from mobile phone masts ... children's skulls are thinner and still forming and tests have shown they absorb more radiation than adults'. What's the science here? Can skulls really 'absorb' EM radiation? The wifi signal is in the same part of the EM spectrum as cellphones but it's not 'similar' to mobile phone masts, is it? Isn't a phone mast several hundred/thousand times stronger? Wasn't safety considered when they drew up the 802.11 specs?"

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434 comments

Sounds familiar (-1, Offtopic)

Anonymous Coward | more than 6 years ago | (#19220357)

Pretty much what global warming FUDers have been doing for years.

Re:Sounds familiar (-1, Troll)

Anonymous Coward | more than 6 years ago | (#19220417)

troll

Re:Sounds familiar (3, Funny)

cosmocain (1060326) | more than 6 years ago | (#19220527)

hell, global warming. isn't that that piece of crap those european scientists promote just to anger and disgruntle the whole hummer-driving-air-conditioning-the-whole-place-am erican-folks? yeah, that's FUD at it's best. actually it's all about selling more european, pseudo-eco-friendly products in the states, to ruin the american markets and thus stopping the war against terrorism by an act of countercultural inner corrosion.

Re:Sounds familiar (5, Funny)

asliarun (636603) | more than 6 years ago | (#19220897)

Consequently, all packets transmitted through WiFi will now need to have the text, "WiFi Kills".

Re:Sounds familiar (3, Funny)

mattpalmer1086 (707360) | more than 6 years ago | (#19220541)

Damn that global conspiracy of nearly 100% of the world's climate scientists! Even the politicians are finally getting in on it, after decades of dedicated FUD spreading by those evil scientists. They must be laughing, laughing I say, all the way to the... err...

 

What's the Science in This? (-1, Offtopic)

Vexler (127353) | more than 6 years ago | (#19220375)

Why did the /. editors allow this drivel to go through, admitting in the brief write-up that there isn't any science behind this?

I thought /. != FUD.

Re:What's the Science in This? (2, Insightful)

Anonymous Coward | more than 6 years ago | (#19220403)

this was all over the news and may cause wifi to be stopped in schools - so any feedback is useful

Re:What's the Science in This? (-1, Troll)

Anonymous Coward | more than 6 years ago | (#19220421)

To remind everyone how spectacularly bad the BBC's science reporting is?

If you poke about on their site you can find the Have Your Say section relating to this program. It's good to see that the vast majority of posters are not fooled.

Re:What's the Science in This? (1)

jimstapleton (999106) | more than 6 years ago | (#19220453)

TFS seems to read as a warning to rampant FUD about to be released about wifi.

I agree, Wifi is dangerous, but only in a computer-security, not a biological integrity, sense.

Re:What's the Science in This? (0)

Anonymous Coward | more than 6 years ago | (#19220521)

Exactly. It's just a bunch of "well this could happen and this may happen and bla bla bla."

If I wanted predictions of death and doom I'd ask the crazy guy on the corner.

To quote Lionel Hutz (5, Funny)

DaveCar (189300) | more than 6 years ago | (#19220601)

From TFS: Their evidence? Well, they admitted there wasn't any

Well, Your Honor, we've plenty of hearsay and conjecture. Those are kinds of evidence.

Re:What's the Science in This? (5, Insightful)

nomadic (141991) | more than 6 years ago | (#19220929)

admitting in the brief write-up that there isn't any science behind this?

Maybe they read the article, which points out various scientists who argue that there IS evidence about it.

I've got to say, the ridiculously emotional backlash I see on /. against ANY suggestion that wifi or cell phone signals MAY cause some adverse health effects is sloppy, anti-science thinking.

I personally don't believe cell phone signals or wifi signals are strong enough to cause health problems. But I'm certainly not going to be arrogant enough to proclaim that there absolutely are no health problems and we shouldn't even look at the problem.

I thought /. != FUD.

Please, half of /. is FUD. /. is only anti-FUD in regards to its pet causes.

Won't somebody please... (5, Insightful)

icthus13 (972796) | more than 6 years ago | (#19220395)

Think of the children!!!
Seriously, it's sad that supposed "news" programs air things like this just to get ratings. What's even sadder is that lots of people believe them, so tech-savvy people like us now have to spend time explaining to Aunt Jane that the big evil wifi will not give her cat cancer.

Re:Won't somebody please... (4, Funny)

mario_grgic (515333) | more than 6 years ago | (#19220599)

give her cat cancer

Is that when there's a cat growing out of her chest cancer?

Re:Won't somebody please... (2)

Applekid (993327) | more than 6 years ago | (#19220979)

I think there was a joke about "women parts" embedded in there somewhere.

(anyone else have visions of the Sarlacc?? *shudder*)

What crap. (5, Insightful)

Mockylock (1087585) | more than 6 years ago | (#19220405)

All day we're around Microwaves, XRays, High voltage lines, lights, televisions and Radio signals. There are TONS, of course... but how much more is actually from outside the atmosphere?

The only thing that's frying our kid's brains are their ideas. I'm not overlooking child safety, but there are WAY more harmful waves out there than WiFi.

In the meantime, their children are outside getting burnt without sunscreen.

Re:What crap. (5, Funny)

cerberusss (660701) | more than 6 years ago | (#19220839)

their children are outside getting burnt without sunscreen.
You think that's bad? The other day, I saw a kid browsing Slashdot in the library.

*shivers*

OMG SOMEBODY THINK OF THE CHIIILDREN

Eek! (5, Funny)

mibalzonya (1072126) | more than 6 years ago | (#19220407)

I suggest aluminum foil hats.

Re:Eek! (2, Informative)

Xest (935314) | more than 6 years ago | (#19220593)

You obviously didn't see the program, one person in it complaining wifi gives her headaches had covered her entire room in tin foil to protect her from it all :p

Re:Eek! (4, Insightful)

CastrTroy (595695) | more than 6 years ago | (#19220735)

I see lots of complaints of this. People who are extra sensitive to electronics and such. I would like to submit these people to a double blind study so that we can prove (or disprove) the effects are real, and not people who just have something else wrong with them that makes them feel more tired, or have headaches, or unable to concentrate, or whatever other symptoms they have. It seems to me like there's a lot of anecdotal evidence, but that there isn't any real studies being done.

Re:Eek! (4, Interesting)

Xest (935314) | more than 6 years ago | (#19220963)

Well again, on the show they said the woman in question was able to tell when wifi was on or off 2/3rds of the time in tests, 66% isn't really a high enough chance for me to believe hers is a real known problem, particularly when they didn't explain her testing methodology, if they only ran 3 tests for example then get 2 out of 3 right is in the correct range of a 50% chance of getting it right by mere guessing should she have got a 4th test wrong.

They did however mention that Sweden recognises electro-sensitivity as an official disability so there is perhaps some credibility in the whole idea, how much is still questionable of course.

FUD (3, Insightful)

Yetihehe (971185) | more than 6 years ago | (#19220415)

Typical wifi - 100mW. 2g Cell tower - 20-100W. In cities they are using micro cells, which typically have about 3W power. There are experiments which show cell phones are a little dangerous, and there are scientist, who tried for years to show there is big danger, but found none and converted to "no harm" camp. So YMMV.

Re:FUD (2, Insightful)

adonoman (624929) | more than 6 years ago | (#19220561)

What kind of scientist goes about trying to "prove" some hypothesis for a year? You don't decide what result you want first and then try and get data to show that you're right. You get the data, and then decide what that data is showing you. At least he was willing to change his opinion when the facts didn't support him (or her).

It's "science" like that that is the source of most of these pseudo-science stories. The flat-earthers, and the circle-squarers, and the perpetual motion people all start out with an idea, and then try and prove they're right -- often with great amusement to others. But in cases like this wi-fi radiation story, bad science can cause big annoyances to us all.

Re:FUD (2, Insightful)

TheRaven64 (641858) | more than 6 years ago | (#19220749)

What kind of scientist goes about trying to "prove" some hypothesis for a year? You don't decide what result you want first and then try and get data to show that you're right. You get the data, and then decide what that data is showing you.
The scientific method is:
  1. Observe.
  2. Hypothesise.
  3. Test.
  4. Repeat.
Presumably this scientist was on phase 3; attempting to test his hypothesis. When they testing indicated that the hypothesis was false, he altered it to conform to the newer observations.

Re:FUD (0)

Red Flayer (890720) | more than 6 years ago | (#19220845)

That's ridiculous. You'd have no way of targeting your research (i.e., figure out what data to collect) without having a hypothesis to test. It's partly semantics, but "looking for evidence in support of" is not the same as "trying to prove" despite how it may be reported sometimes by the Beeb or other networks.

Re:FUD (4, Insightful)

VeriTea (795384) | more than 6 years ago | (#19220751)

Output power doesn't tell the whole story, proximity is much more important. Electromagnetic power density dissipates at the inverse square of the distance from the emitter.

All you have to do is consider the receive power. It is typical to receive a wifi signal at -65dBm, while a cell signal indoors is seldom stronger then -80dBm. Even if you consider multiple channels and multiple carriers on each cell tower, you would seldom get a composite power level greater then -70dBm indoors. -65dBm is approximately 3 times stronger then -70dBm. Of course these are typical levels, but when you consider how many wifi networks you usually pick up in your own home (esp. apartment), you will almost always receive a far greater exposure to electromagnetic radiation from wifi then from cell phone towers.

Full disclosure: I perform power density theoretical studies and measurement levels for the wireless industry, and also design in-building wireless repeater systems so I have a fair bit of experience here.

Re:FUD (2, Informative)

mdsolar (1045926) | more than 6 years ago | (#19220801)

So, your WIFI is 1 meter away and the cell tower is 1 kilometer away, which delivers more power where you are at. Take the cell tower number and divide by a million (1000^2) and you'll see that WIFI yields greater exposure. Doesn't mean there is a problem, but it is not just power level at the antenna that is important.
--
Fusion power from your roof: http://mdsolar.blogspot.com/2007/01/slashdot-users -selling-solar.html [blogspot.com]

WiFi is microwaves (5, Informative)

QuietLagoon (813062) | more than 6 years ago | (#19220423)

Can skulls really 'absorb' EM radiation?

802.11b/g uses 2.4GHz radio waves. That's the same frequency range as microwave ovens. Microwave ovens work because the microwaves are absorbed by the bonds in the water molecules of food (which is why dry food does not cook in microwave ovens).

So yes, human tissue that contains water can absorb WiFi radiation. That is a fact.

What is not known is: how much absorption of that radiation is bad for the kids?

Re:WiFi is microwaves (3, Interesting)

StarfishOne (756076) | more than 6 years ago | (#19220491)

I've always wondered why these networks use 2.4GHz radio waves.

I'm not a physicist, so really: is there an advantage to this frequency? Why not 1.2GHz.. or 3.6GHz, etc.? Why something so close to the frequency range of microwave ovens?

If this is a really dumb question, I already ask for forgiveness. :)

Re:WiFi is microwaves (4, Informative)

QuietLagoon (813062) | more than 6 years ago | (#19220577)

802.11a uses the 5GHz range, out of the way of microwave ovens.

2.4GHz was used because it was available for use, i.e., it would not interfere with frequencies already allocated to other services in the microwave area.

In other words, the thought process (if you can call it that) was not, "let's find a frequency for 802.11b that is free of interference from other sources". It was more along the lines of, "let's find a frequency for 802.11b so that 802.11b won't mess up anything of import, i.e., microwave ovens don't really care about interference from your wireless router.

By the way, the same "thought" process was used to pick a frequency for the 2.4GHx wireless phones.

Re:WiFi is microwaves (1)

Shakrai (717556) | more than 6 years ago | (#19220623)

n other words, the thought process (if you can call it that) was not, "let's find a frequency for 802.11b that is free of interference from other sources". It was more along the lines of, "let's find a frequency for 802.11b so that 802.11b won't mess up anything of impor

I'm pretty sure that "Let's find a frequency that's unlicensed so we can legally use it" was part of the thought process too.......

Re:WiFi is microwaves (0)

Anonymous Coward | more than 6 years ago | (#19220727)

It was more along the lines of, "let's find a frequency for 802.11b so that 802.11b won't mess up anything of import, i.e., microwave ovens don't really care about interference from your wireless router.

Well that's just fucking retarded; where was the thought process of "wireless routers -will- really care about interference from a microwave oven"?

Re:WiFi is microwaves (0)

Anonymous Coward | more than 6 years ago | (#19220981)

In the intereste of making cheap devices, microwave ovens are very well shielded to keep the microwaves inside the oven, dipshit. Microwaves that leak out don't cook the food and in turn require a bigger microwave transmitter to cook the food. It's cheaper to build a well sealed oven then it is to build a bigger microwave generator.

Re:WiFi is microwaves (3, Informative)

Shakrai (717556) | more than 6 years ago | (#19220585)

I've always wondered why these networks use 2.4GHz radio waves.

I think it mainly had to do with the fact that the same part of 2.4GHz is open for unlicensed use globally. The other unlicensed ISM (industrial-scientific-medical) bands in the United States are used for other stuff in other nations. The easiest example is 900mhz. Part of it is available for unlicensed use in the United States. But as anybody with a quad-band GSM phone knows, that's a cellular band in most of the rest of the world.

Re:WiFi is microwaves (1)

yaroze32 (689185) | more than 6 years ago | (#19220611)

2.4 Ghz is unlicensed spectrum, so that means they can produce tons of things for this spectrum, and and not bother with you haveing to get a license to operate it.

Re:WiFi is microwaves (1)

jasen666 (88727) | more than 6 years ago | (#19220649)

I don't believe there is a scientific reason for it. I think this was just the range that the FCC allocated as usable for this purpose (and other purposes).
This band, plus the ISM 5Ghz band.

Re:WiFi is microwaves (1)

LarsG (31008) | more than 6 years ago | (#19220807)

Why 2.4GHz? Because it one of very few frequency bands that are internationally available for unlicensed use. Which is also the reason why microwave ovens, some cordless phones, bluetooth and lots of other stuff use it.

http://en.wikipedia.org/wiki/ISM_band [wikipedia.org]

Re:WiFi is microwaves (1)

jasen666 (88727) | more than 6 years ago | (#19220915)

Cross microwave ovens off that list, and you're right. :)
They a specific frequency for a very specific reason.

Re:WiFi is microwaves (5, Informative)

Andy Dodd (701) | more than 6 years ago | (#19220951)

I believe there is a scientific reason for the ISM band being there - I think water has a bit of an absorption peak in the 2.4 GHz region.

For this reason, 2.4 GHz wasn't too hot for long-haul communications due to water vapor in the air, so no one was in a rush to license spectrum for it, and no one fought designating it as an "Industrial, Scientific, Medical" band. (with the primary use in all three of those categories being to take advantage of that water absorption peak for heating.) Now, because the band is such a cesspool, no one minded allowing low-power unlicensed communications in that band.

Now, as to the health effects of this - Yes, the water in your body is more likely to absorb 2.4 GHz RF. No, that absorption will not do any cumulative damage. Absorbing 2.4 GHz RF will make the water molecules in your body vibrate a little more (i.e. it will heat you up.) At high powers, this does become dangerous as the heat basically cooks you from the inside (just like a microwave oven). At low powers (with 802.11 being a great example), the body is able to safely dissipate the heat rapidly enough so that not only is no damage done, the change in temperature at any point in the body is negligible. You're more likely to get burned by touching the heatsink of the RF amp than you are by touching a circuit trace carrying RF at those power levels.

RF radiation is nothing like nuclear radiation - the critical difference is that nuclear radiation is ionizing, that is to say that it can not only vibrate molecules a bit, but it has enough energy to alter them. This has the effect of "flipping bits" in your DNA and other such nasty stuff. Since "bit flipping" can have cumulative effects, low levels of ionizing radiation can be dangerous in the long term, because the damage accumulates. With RF, it doesn't unless power levels are so high as to induce temperatures that cause thermal damage.

Prior to graduate school, I worked at a company that built RF power amplifiers for cell towers (30-45W average power output), and many of my coworkers had been working with microwave RF amps since the very first cell system Motorola deployed. (Yes, we had some ex-Motorola old hands there, who had interesting stories from the early days when the system designers were also heavily involved with the installation process of new base stations.) No health problems whatsoever.

Since graduate school, one of the tasks of my department is taking equipment through EMI testing. We're frequently right at OSHA RF exposure limits - no health problems with any of us (Well, at least no new ones that weren't preexisting conditions), even our mentor who has been doing this for 20-30 years.

Re:WiFi is microwaves (1)

CastrTroy (595695) | more than 6 years ago | (#19220583)

That's the same frequency as many cordless phones. How many people spend hours with one of those things right up against the side of their head. Why isn't anybody complaining about those. As far as I remember from my physics classes electromagnetic waves lose power as a square of the distance. And since my cordless phone and wifi network have similar range, they must use the waves of the same strength. So, I must say that if we're going to be worried about wifi, that we should all throw out our cordless phones right now.

Re:WiFi is microwaves (1)

D-Cypell (446534) | more than 6 years ago | (#19220905)

That's the same frequency as many cordless phones. How many people spend hours with one of those things right up against the side of their head. Why isn't anybody complaining about those?

You have got to be kidding!!

Re:WiFi is microwaves (1)

Idbar (1034346) | more than 6 years ago | (#19220653)

In fact, isn't that frequency also used in cordless phones? That means that girls talking on the phone for hours will have their brains toasted already!

Oh wait...

Re:WiFi is microwaves (3, Informative)

morgan_greywolf (835522) | more than 6 years ago | (#19220787)

Typical 802.11b/g = 1 mW - 100mW
Typical microwave oven = 750W-1500W (750,000 - 1,500,000 mW)

Big difference.

Re:WiFi is microwaves (1, Funny)

Anonymous Coward | more than 6 years ago | (#19220805)

OMG! Now I got it! So THAT IS the real reason of global warming! We filled this planet (75% of water) with ovens, cordless phones, cellular phones, WiFi and we have made it a huge microwave oven! No wonder why there is "global warming".

Re:WiFi is microwaves (1)

CryogenicKeen (1088911) | more than 6 years ago | (#19220817)

So if its a fact that 2.4 GHz radiation is harmful what is the risk then? What I don't understand is that if what other posters say is true and its basically the same as the cellphone hasn't the research been done on this for years? I mean we've had cellphones for what 20 years and people are still screaming my cellphone COULD give me cancer? I have panic attacks about stupid things and I just realized our wireless hub is right underneath this desk and I've been sitting here 5 out of 7 days of the week for the past 9 months should I be worried that I'm going to get testicular cancer or that the Wireless Router will fry my testes like 2 eggs in a frying pan? I still try to keep all my cellphone calls short and even sometimes keep the thing aw away from my head as I can without looking like a total dork and hearing the person. I know statistically that I have a better chance of dieing millions of other ways but how can I trust technology's like these if supposed expert scientists keep coming out every couple of months and saying: Wait we got it all wrong you ARE kill yourselves with cellphones and Wifi! I mean every conspiracy theory has a grain of truth in it how do you separate the irrational fear, from the media hype, from the die hard conspiracy theorist that KNOWS they are right, from supposed "solid" scientific research? I mean not ALL conspiracy's are wrong every one in a blue moon turns out to be right doesn't it?

Re:WiFi is microwaves (1)

Reality Master 101 (179095) | more than 6 years ago | (#19220961)

So yes, human tissue that contains water can absorb WiFi radiation. That is a fact.

Well, for loose definitions of "absorb", I suppose, which makes it sound like it makes human tissue radioactive, which it does not. Microwave ovens work by vibrating water molecules with the EM radiation. The worst a WiFi station will do is make your skin heat up a tiny amount (compare 750 watt microwave oven blasting into an enclosed chamber to 100 MW radiating in all directions).

What is not known is: how much absorption of that radiation is bad for the kids?

Actually, that is known: exactly none.

so... (2, Funny)

cosmocain (1060326) | more than 6 years ago | (#19220429)

'The radiation Wi-Fi emits is similar to that from mobile phone masts ... children's skulls are thinner and still forming and tests have shown they absorb more radiation than adults'.
it absorbs? wowy! so i gotta keep children away to avoid serious wifi-connection-troubles. damned, those little buggers seem to interfere with almost anything!

Won't someone think of the children? (2, Funny)

kannibal_klown (531544) | more than 6 years ago | (#19220435)

Gah! Won't someone think of the children!?

If we use 802.11, the terrorists win.

I'm sure it's worth study, and I personally think WiFi is used too much. I'm not saying we shouldn't use it a lot, but I know some homes and businesses that might just be better off with some CAT cables. I mean, if all of your computers in your 1 bed apartment are desktops, why go WiFi?

switch of the sun, NOW! (1)

Down_in_the_Park (721993) | more than 6 years ago | (#19220441)

all this deadly EM radiation will kill our children, and than there is this bad, bad, bad radiation from the stars, gamma ray burst anybody? So let's destroy all this stars, maybe with a, a ...star destroyer, uh wait, never mind.

"Can skulls really 'absorb' EM radiation?" (2, Funny)

2008 (900939) | more than 6 years ago | (#19220445)

Of course they can. Everything does. Notice how when you put your head near a source of radiant heat it feels warm?

"Do not look into laser with remaining eye" is also appropriate here...

Researchers. On. Drugs. (4, Informative)

swschrad (312009) | more than 6 years ago | (#19220455)

not a pretty sight, is it?

the FCC has specifications of radiation density versus frequency that are limits in their rulebooks, limits used to isolate access to radio facilities from microwaves to commercial broadcasters... to ham radio operators burning electrons in the basement. these have been codified by medical research. if you're going for an advanced ham license, you have to study the milliwatts per meter limits, the question occasionally comes up on the test.

so there are 3/4 million americans who know this, not just ten academics in the tower.

where the hell did this whining of Luddites come from, and why wasn't it left there?

Who believes BBC (-1, Troll)

Anonymous Coward | more than 6 years ago | (#19220459)

Isn't this the same socialist government owned TV station that accused Scientology of being a cult?

Re:Who believes BBC (0)

Anonymous Coward | more than 6 years ago | (#19220573)

Isn't this the same socialist government owned TV station that accused Scientology of being a cult?
Yesterday, I met Tom cruiseing in the park. Boy, is that boy hot!

Re:Who believes BBC (1)

MLease (652529) | more than 6 years ago | (#19220689)

They said that???!?! Hmmm.... I guess I'll have to take them a bit more seriously, then....

-Mike

Good analisys at El Reg (2, Informative)

supersnail (106701) | more than 6 years ago | (#19220473)

Here [theregister.co.uk]

Basicaly in the old country they have a government official who is unprepared to admit radio waves, mobile phones etc, are safe; no matter what the evidence.

 

Re:Good analisys at El Reg (1)

Goffee71 (628501) | more than 6 years ago | (#19220705)

Next week on Panorama - Laptops burn your legs. Next week on Panorama - Smashing a monitor on someone's head will hurt them Next week on Panorama - Nothing scary left to report Next on BBC1 - A new sitcom about people complaining about the weather

Re:Good analisys at El Reg (0)

Anonymous Coward | more than 6 years ago | (#19220967)

If it's just one bureaucrat, then why just kill the motherfucker?

radiation buzz buzz (3, Insightful)

quibbler (175041) | more than 6 years ago | (#19220479)

Mobile phone towers are many, many times more total output. Yes, both transmit in the microwave spectrum, but the 'notch' in the microwave spectrum that resonates water (and thereby heats your food, cooks your brain) is extremely tight (2.45 Ghz). If you're above it or below it, the water molecules in your body (or food) simply won't vibrate/resonate and there's no heating. And yeah, people use 'radiation' all the time to invoke the panic of ionizing nuclear radiation (bad) with electromagnetic radiation (mostly harmless). (Meanwhile these same people go suntan in the name of health, basking in the glow of an unshielded fusion reactor. Yay humanity.) ...People who live by the sword get shot by those who dont.

2.45GHz is NOT the resonant frequency of water... (3, Informative)

Ellis D. Tripp (755736) | more than 6 years ago | (#19220813)

The operating frequency of microwave ovens was chosen to be in an unlicensed (ISM) frequency band, that would provide good penetration into foods, and lent itself to the mass production of inexpensive magnetron tubes.

The lowest resonant frequency for a water molecule is 22.235 GHz, or nearly 10X the operating frequency of a microwave oven.

2.45 GHz isn't maximum absorbance (3, Informative)

littleghoti (637230) | more than 6 years ago | (#19220931)

Actually, 2.45 GHz isn't the maximum of the absorbance for microwaves. If it was, all the energy would be dumped at the surface of food, and there would be virtually no penetration. Water absorbs over a broad spectral range, at least in the liquid phase, where quantised rotational bands can be ignored.

And what you say about the different energies of radiation is mostly true, although EM radiation covers a range that includes UV, x-rays and gamma radiation, which are not very good for you.

Website story (3, Insightful)

dylan_- (1661) | more than 6 years ago | (#19220485)

The BBC website has a Wi-fi health fears are 'unproven' [bbc.co.uk] story which addresses this. My favourite quote, from Professor Will J Stewart:

"This is not to say that all electromagnetic radiation is necessarily harmless - sunlight, for example, poses a significant cancer risk; so if you are using your laptop on the beach make sure and get some shade."

Re:Website story (1)

Zelos (1050172) | more than 6 years ago | (#19220537)

Even that story seems to have a fairly loose grip on what radiation is: "The type of radiation emitted by radio waves (wi-fi), visible light, microwaves and mobile phones has been shown to raise the temperature of tissue at very high levels of exposure...

The BBC should know better... (4, Insightful)

Xest (935314) | more than 6 years ago | (#19220523)

Frankly the BBC was irresponsible in showing this episode of Panorama. I'm against censorship, but informational programs produced by a tax-payer funded media outlet should not be spouting such paranoid, biased crap as Panorama did last night.

This is arguably the worst case of the BBC scrambling for ratings I've ever witnessed. Never before have I seen them stoop so low to try and raise viewing figures. I was sat watching it waiting for the part where they offer the opposing view of the situation to allow people to make their own minds up, unfortunately however, that never came - it was one sided anti-wifi propaganda all the way through, from start to finish.

About the only attempt at offering an opposing view was the brief mention that the WHO states that there is no known risk of wifi at this time, this brief mentioning was followed by a couple of minutes of slagging off the credibility of the WHO.

I'm no expert when it comes to wifi, radiation and so forth and I'm not claiming that wifi is 100% safe - it may well pose risks. The problem with the program however seemed to be that it's entire argument is based on the premise that there is some other danger to human health from radiation other than the heating effect, and from what I've read elsewhere, there is absolutely no evidence that there is any effect other than the heating effect. I'm sure those with better scientific knowledge may be able to correct me on this if I'm wrong, but if it's true as has been reported by other news outlets (and in fact even by the BBC themselves online) then the majority of the program was fundamentally flawed in it's arguments.

What bothers me most is that we've gone from one lazy teacher looking for an excuse to get time off work claiming that wifi gives him headaches to a national wifi scandal. The worst part is that most reports that refer to the teacher in question who sparked this row ignore the fact that in scientific tests the teacher could neither a) tell whether wifi was on or off and b) now claims he gets these headaches wherever he is, even when not around wifi!

If Wifi does indeed pose a threat then I agree we need to do something, but thus far this seems equivalent to the whole terrorism/think of the children/drugs/computer games make people kill FUD.

Re:The BBC should know better... (2, Insightful)

jrumney (197329) | more than 6 years ago | (#19220657)

Frankly the BBC was irresponsible in showing this episode of Panorama. I'm against censorship, but informational programs produced by a tax-payer funded media outlet should not be spouting such paranoid, biased crap as Panorama did last night.

What I find most disturbing, is that they are probably helping the Scientologists make their case against last week's Panorama by following it up with this tripe.

Leukaemia (5, Interesting)

weliwarmer (569280) | more than 6 years ago | (#19220525)

My son was diagnosed with leukaemia (AML15 for those interested) on his 1st birthday. My first trip home from the hospital I turned of the wireless router, cordless phones and my mobile/cell. He's now 3, built like an ox and hopefully fixed for good.

My neighbours all have wireless, cordless and mobiles so I eventually turned all mine back on. Two years on and no-one else in the house, including my 2 other boys, have cancer.

Who knows what caused it. Live life to the full, make the kids smile and if low power wireless gadgets worry you, please get out more.

Re:Leukaemia (0)

Anonymous Coward | more than 6 years ago | (#19220655)

Anecdotal evidence is great. My son is almost 2 and lives in a house with 2 wireless phones, 2 cell phones, a WiFi router and a microwave. We also have an old tube TV which probably does more harm than all the other items combined. So far, no sign of any cancer or leukemia.

While I am glad that your son is fine now, there is simply no evidence that radio waves caused his initial condition.

Trade one for the other (4, Funny)

Applekid (993327) | more than 6 years ago | (#19220529)

So if WiFi can give you cancer, what can a bunch of loose network cables strewn on the floor give you?

It's not the flight I'm afraid of, it's the notebook's landing that's the dealbreaker.

The next ADHD (1)

faloi (738831) | more than 6 years ago | (#19220535)

It's odd how the blame essentially everything on Wi-Fi. If only someone would invent a pill that helps the body cope with radiation (like potassium iodide, but for wi-fi) and then sell it to the UK health service at a tremendous markup! Then the children would be safe.

We can even make scary sounding slogans to remind people to take their pills. "Why die for wi-fi? Take PlaceboXL and live!"

all a matter of degree (1)

r00t (33219) | more than 6 years ago | (#19220631)

Come on, this is obvious.

Radio waves are harmful. We know this. There is no cut-off point at which they suddenly go from harmless to harmful.

However...

We've been living with this stuff for years, and we're not noticably dropping dead in any way related to it. It's in the noise compared to all the other bad things in our lives.

This is approximately item #6589726 on our list of killers. Relax. Have a cigarette.

Microwave Radiation (1)

dlhm (739554) | more than 6 years ago | (#19220685)

I would be more worried about The long term exposure to X-Ray and other Radiation coming from CRT TV's that our fat little kids sit infront of all day eating potato chips, rather than Wifi Radiation. Maybe we shoudl do another dory on that.. the TV or the Potato Chips.

remember dihydrogen monoxide? (0)

circletimessquare (444983) | more than 6 years ago | (#19220697)

i think it was some kid whose science fair experiment consisted of showing how stupid most people were about basic science by scaring them about "facts" about dihydrogen monoxide. here is a good spoof site [dhmo.org]:

Some of the known perils of Dihydrogen Monoxide are:
-Death due to accidental inhalation of DHMO, even in small quantities.
-Prolonged exposure to solid DHMO causes severe tissue damage.
-Excessive ingestion produces a number of unpleasant though not typically life-threatening side-effects.
-DHMO is a major component of acid rain.
-Gaseous DHMO can cause severe burns.
-Contributes to soil erosion.
-Leads to corrosion and oxidation of many metals.
-Contamination of electrical systems often causes short-circuits.
-Exposure decreases effectiveness of automobile brakes.
-Found in biopsies of pre-cancerous tumors and lesions.
-Given to vicious dogs involved in recent deadly attacks.
-Often associated with killer cyclones in the U.S. Midwest and elsewhere, and in hurricanes including deadly storms in Florida, New Orleans and other areas of the southeastern U.S.
-Thermal variations in DHMO are a suspected contributor to the El Nino weather effect.

the point is, i suggest someone with more time than me put up a "dangers of 450-750 terahertz radiation [wikipedia.org]"

did you know the following about 450-750 terahertz radiation:

-excessive exposure can cause blindness
-longterm exposure can damage the skin
-used in advanced military equipment
-children are bombarded by it on a daily basis and yet no government agency regulates our exposure

someone wittier than me can probably think up some better ones

FRAUD ALERT -- Slashdot sucked in again! (0, Flamebait)

Futurepower(R) (558542) | more than 6 years ago | (#19220725)

FRAUD ALERT -- FRAUD ALERT -- FRAUD ALERT

Slashdot editors apparently don't read the comments on the stories they post. Also, Slashdot editors apparently didn't listen in Physics class. This is the fifth time in 3 years that they have fallen for the same fraud, if I count correctly. Some of my other comments:

Max Planck would be very sad about this. [slashdot.org]

Distinguish between real science and junk science. [slashdot.org]

Planck's constant [wolfram.com] is so small that interactions between electromagnetic waves and molecules cannot be chemically specific. The 2,000 MHz radiation from WiFi is felt as heat, a very, very small amount of heat, almost certainly not measurable.

Anyone may have theories. Someone could say, for example, that pigs have started flying and they have been eating the bees. (The bees are dying because of bad [informatio...ration.com] management [bushfarms.com]; the organic beekeepers aren't having problems.) The only real science, however, is based on what is already known through experimentation. That requires an understanding of what is known.

Re:FRAUD ALERT -- Slashdot sucked in again! (1)

ambrosen (176977) | more than 6 years ago | (#19220867)

The story here is that a should-be-reliable investigative news documentary programme is being Fox-ish and grubbing up hysteria, not that it's likely wifi is harmful. At least, that's the way I see it.

Voodoo Science and health scares (0)

Anonymous Coward | more than 6 years ago | (#19220739)

"Voodoo Science", by physicist Robert Park, predates the recent health scares about wireless networking (effective radiated power: 100 milliwatts of non-ionising radiation), but talks about a similar health scare about cancer caused by high voltage power lines. In that case, no evidence was ever found to link power lines to leukemia, despite expenditure of billions of dollars on research due to public outcry. (Worth reading this book if you have not already - it's an accessible well-written science book).

Boo hiss to the BBC for encouraging hypochondriacs who think that radiation always means "causes cancer". Perhaps the BBC should turn off it's television transmitters to reduce the "risk" (typical ERP of a UHF TV transmitter: 1 megawatt)? At least that would stop the scare stories reaching Britain's hypochondriacs.

Radiation is bad, but not our worst problem (1)

Theovon (109752) | more than 6 years ago | (#19220741)

Of course, it doesn't seem overly healthy to me to put any kind of artificial radiation source near your body. But frankly, I think our health is being heart a great deal more by pollution, GMO foods, and the excess of allergens in our diet from things like soy, corn, dairy, and wheat.

Crap (probably) (1)

Moby Cock (771358) | more than 6 years ago | (#19220761)

This is garbage (probaly...see below). Wi-Fi frequencies are in thr non-ionizing range, and as such will not cause any tissue mutations or changes. The radiation is absorbed by tissues (usually by the water therein) and creates heat -- this is how a microwave oven works. However, unlike an oven, the world is not a resonant cavity so the energy dissipates very quickly and poses no threat other than a heating/cooling cycle.

In the ionizing range the high energy radiation actually punches out nuclear particles and cause aplha or beta decay. This is the cancer causing bad sort of radiation. However, there are no communication technologies that use such high frequencies.

Having said all that, there is still a small collection of researchers who believe that long term exposure to non-ionising radiation is an issue. It is a very difficult thing to study because of the prevalence of EM radiation in the world (try and find a control!). Further, modeling a complex system like a human head -- having dozens of different dielectric and conductive tissues and substances -- is extraodiarily complex.

Most RF scientist have come to a consensus that non-ionising radiation is safe, but there is still some research to be done. But hey, that is just responsible science, no?

correlation != cause (1)

david_bonn (259998) | more than 6 years ago | (#19220793)

  • 1970's: hysteria about radiation from microwave ovens
  • 1980's: hysteria about radiation from power lines (well, really the late 80's)
  • 1990's: hysteria about radiation from cell phones
  • 2000's: hysteria about radiation from wi-fi
I know of no imaginable mechanism that allows gigahertz-frequency radiation at low power levels to break chemical bonds. That's what you'd need in order to have microwave be harmful. End of story. The problem is that if you are dealing with a relatively rare disease (like a childhood cancer) it is extremely easy to produce a spurious correlation with almost anything. Since you're dealing with an effect right on the edge of statistical noise, and since a lot of researchers are less than diligent about making sure they aren't fooling themselves (they often "know" there is an effect and so they'll keep poking at the data until they get one). Top it all off with the sad fact that most people (many scientists, nearly all journalists) assume that correlation == cause.

Re:correlation != cause (1)

aicrules (819392) | more than 6 years ago | (#19220945)

unfortunately it all started from:
  • 1940's: hysteria about radiation from nuclear weapons

Re:correlation != cause (1)

Ihlosi (895663) | more than 6 years ago | (#19220991)

I know of no imaginable mechanism that allows gigahertz-frequency radiation at low power levels to break chemical bonds.



What about intra-molecular bonds (those that influence protein folding) ?

scientists (1)

mapkinase (958129) | more than 6 years ago | (#19220819)

Real scientists pose scientific hypotheses, then propose studies to test those hypotheses, then publish it and only then the media raises alarm.

Some scientists do not do that. Instead they go straight to the media. I have seen some in my field. They were ridiculed privately.

Lawyers that disbehave are disbarred. I wish something like that could be done to scientists.

Think of the Sunshine (1)

Ilex (261136) | more than 6 years ago | (#19220821)

I wonder how many of these soccer mom's who are worried about wifi "radiation" think nothing of taking their kids on Holiday and exposing them to a far more powerful form of radiation otherwise known as "Sunlight" and unlike wifi prolonged exposure to UV radiation has "proved" to be harmful.

Panorama is broadcast on Mondays..... (1)

stiggle (649614) | more than 6 years ago | (#19220833)

But then it is mentioned on the BBC page about the program, and we know people don't read the articles :-)

But It's the BBC! (-1, Flamebait)

AC5398 (651967) | more than 6 years ago | (#19220871)

C'mon, this is the BBC that spouted this drivel. This is the same BBC that attempted to eviscerate the IKEA guy because he wasn't having IKEA immediately follow/obey the latest politically-correct fad of the week. Oh, and his politely repeated refusal to take the company public had the interviewer just hysterical at the injustice of it all.

It must be a slow news day in p.c. land or something.

I changed my sig today [on-topic] (3, Informative)

Flying pig (925874) | more than 6 years ago | (#19220903)

After re-reading Richard Feynman's lecture on Cargo Cult Science. With its demolition of "experiments" without controls, and how people kept on doing pointless lab rat experiments after the methodology was debunked, it's a sad saga - which is just as true today after so much "progress".

Unfortunately, in the UK at least, the number of scientifically trained journalists can probably be counted on one of Ben Goldacre's fingers.

Interesting that none of the phone mast posts seem to have remembered the inverse square law - sorry if you did and I missed you - which mean that radiation levels at the ground are a tiny fraction of what you get from the phone. And that nobody has mentioned all the radiation we used to get from TV and radio sets. As I recall, the radiation you get from an old tube superhet set (from the IF) is much more intense than the radiation from WiFi. It is lower frequency, but then the skin effect is less, and as anybody who ever played about with NMR will recall, VHF does things to organic molecules.

We'd better take action now. Let's get rid of all that nasty radioactivity - oops, Madam, there goes your granite kitchen work surfaces and your low-sodium salt. And all the radiation sources beginning with the most intense. So we've now turned off the Sun, mobile phones, radio, TV, electrical generating. We can't use coal (have you looked at what you get in the ash). So we can just sit in the dark and freeze.

As for the leukaemia cases - I have long believed that a far more convincing explanation is exposure to farm chemicals, pesticides, and the new virus and bacterial strains resulting from population movement. It is possible that farming overspray with chemicals which have been subsequently banned is a more probable cause of leukaemia clusters than, say, living near a rural electrical supply line. In the UK, and probably in the US too, the parts of Government which deal with farming tend to be extremely secretive and their decisions are often hard to understand. To my mind, they are far more likely to suppress information about such things than the relatively open parts of Government which deal with non-farming health and safety.

analyze the protocol (0)

Ep0xi (1093943) | more than 6 years ago | (#19220939)

the problem would not be related to the band of 2.4ghz but to the packs of waves related to the data flow tipical of the internet. because when the flux of radiation is a constant the body can change the chemistry involved in the cells to "absorb" that radiation without harm, but when the radiation flow is not constant, you became an laboratory rat, because the body cannot adapt to the changing microwaves, but it can adapt to a standard microwave flow as could be the noise in the universe.

Can't Be Too Safe! (1)

knapper_tech (813569) | more than 6 years ago | (#19220965)

It will take years of testing to figure out whether all this darned radiation is affecting our brains...but until then, since when was anyone hurt by a tenfoil hat?!

Typical Panorama bullshit (1)

Conor Turton (639827) | more than 6 years ago | (#19220975)

Sadly, it was a report indicative of the way BBC Journalism has gone down the pan. Jeremy Vine, host of Panorama, is noted for a "Daily Wail think of the chiiiilldruun" type of sensationalist reporting.

There were very few hard facts in the programme. The part showing the strength of the signal at a phone mast and laptop was very dubious. At no point were you shown what was being measured. All you were shown was a display that showed one value then the other. For all we know, it could have been showing dB levels which have bugger all to do with how strong the signal is.

Also the fact that Wifi signals are 600 times lower than the govt guidelines was glossed over as quickly as possible.

The usual string of scientist who would agree that the sky is pink in order to get on TV were trotted out.

Once upon a time, Panorama was a programme to be taken seriously. Now it is nothing more than a mockery.

Stay out of the sun... (1)

flyingfsck (986395) | more than 6 years ago | (#19220977)

The microwave radiation from the sun is much more powerful than WiFi, so anyone worried about radiation should remain in his mother's basement...
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