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How Bad Can Wi-fi Be?
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?"
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.
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.
"Please, shut up. Just when I think you can't say anything more stupid, you speak again." -Archie Bunker.
I suggest aluminum foil hats.
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.
Extreme Programming - Redundant Array of Inexpensive Developers
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?
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?
if this is supposed to be a new economy, how come they still want my old fashioned money?
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.
Igor Presnyakov stole my hat
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.
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.
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.
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.
More Twoson than Cupertino
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...
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.
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.
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Consequently, all packets transmitted through WiFi will now need to have the text, "WiFi Kills".
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.
Pining for the fjords
admitting in the brief write-up that there isn't any science behind this?
/. against ANY suggestion that wifi or cell phone signals MAY cause some adverse health effects is sloppy, anti-science thinking.
/. != FUD.
/. is FUD. /. is only anti-FUD in regards to its pet causes.
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
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
Please, half of
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.
Different parts of the EM-spectrum probe different aspects of molecules. (Visible light probes electronic structure, infrared light interacts with molecular vibrations, etc.) Even the radiofrequency range of the spectrum interacts with molecules in a chemically-specific way: microwave-region EM-radiation probes the rotational modes of molecules, and radiofrequency spectroscopy can also probe nuclear states (see NMR).
If I've misunderstood what you meant, please set me straight.
(By the way, I do agree that the energy from a WiFi signal will be absorbed by most common materials and lead to a barely noticeable increase in temperature. But that doesn't mean that the process is not chemical-specific. For instance, some materials will absorb more of the WiFi signal than others.)
Well I don't think programs that only exist to scare you are worthwhile. I've never seen a Panorama program that wasn't a scare-fest. When you watch one on a topic you know nothing about the scientists seem well informed and the threats seem genuine. It's only when you watch a Panorama program on a topic you're remotely familiar with that you realize what nonsense it is.
One of them was about the dangers of black holes. They'll boil the oceans, suck the life right off the planet, there's a super massive one at the center of our galaxy, they feed and then they stay silent, drifting through space until WHAM. Lots of sound bytes of scientists saying "it's only a matter of time", "you can't see them, but we know they're there", "we have no idea how many there are", etc. In only 5 billion years our galaxy will collide with another one, and we might drift right into that galaxy's super massive black hole, etc, etc.
It's that sort of programming, and if they convince laypeople that more money needs to be spent on researching this than is really necessary it only does damage.
// MD_Update(&m,buf,j);
They got it all wrong. The problem isn't with WiFi, the problem is when the signal carries the kill bit, passing through your body and causing extreme cellular damage. That's why most of the time the studies show up nothing.
"A little knowledge is a dangerous thing. Drink deeply or not at all."
Y'know, I dislike people like you. Science is NOT a religion, whatever you might make of it. Entire fields have been fundamentally wrong about their area of study before, and will be again. Given that the modern anthropogenic global warming schema is being driven mainly by political funding it is highly possible such is the case here, especially since it's such a young science. Of course, getting the religious fanatics to admit this is next to impossible, and rather disconcerting. Especially given the amount of ostracization that anyone who begins to speak out about the matter experiences.
FYI, I know perfectly well how science operates. I was not making any personal judgement on whether global warming is real, caused by human activity, or by the flying spaghetti monster.
I was attacking the position (hopefully with a little humour) that global warming is all FUD. That position seems untenable; that a large majority of the world's scientists would all conspire to promote falsehood. They may be entirely wrong, but the majority are in broad agreement.
Given that the consequences of not acting on this information may be disastrous, the precautionary principle suggests that we listen to them. Taken to its logical extreme, you would be advocating never acting on any scientific advice, as it *might* be wrong.
Expect the USA to counter with "Freedom Packets"