Aug 16 2010

Banning Wi-Fi From Schools

In the town just north of where I live the middle school was completely torn down and an entirely new middle school was built. The reason for this was concerns that mold in the old school was making children sick.

Apparently, Wi-Fi is the new mold. In central Ontario parents are lobbying the school to turn off the Wi-Fi due to fears that it is making their children sick. You can take the news report of the parents concerns, time-warp about ten years in the past, and substitute “mold” for “Wi-Fi” – the arguments are the same, and the evidence as weak, but the identified problem has just shifted.

The Evidence

Let’s start by reviewing what we currently know about the health risks of Wi-Fi – wireless signals used to connect computers to a network or the internet. From a basic science perspective, there is little plausibility to the notion that Wi-Fi radiation would have any health effects. The amount of energy that is absorbed by a person living in a Wi-Fi field is negligible – less than 1% of exposure from a typical cell phone and well below current safety levels.

I have written about the risk from cell phones recently also. To summarize, there is no compelling evidence at this time that there is a health risk. The evidence so far seems to rule out any significant risk for adults with up to 10-15 years of exposure, but not yet for children or for >15 years exposure. In short, if there is any adverse health effect it must be tiny to be so difficult to detect – and Wi-Fi causes only 1% of the energy exposure as cell phones.

Further, the hypothesized risks of non-ionizing radiation (insufficient energy to break chemical bonds) is considered by many to lack plausibility due to the fact that so little energy is transferred to tissue.For non-ionizing radiation, regulations have focused on the thermal effects – heating tissue – which can occur depending upon the specific frequencies used and how easily it is coupled or transferred to tissues. This is the same effect exploited by microwaves (a form of non-ionizing radiation) to heat food.

The current regulations are largely based upon the thermal effects of EMF exposures – exposures are low enough to prevent significant heating of tissues. Some argue that this is not enough, however, and that there may be non-thermal biological effects, and therefore safety limits should be lowered.

While I agree with those who argue that a significant non-ionizing, non-thermal effect is unproven and implausible, a biological effect is not impossible, and so epidemiological and clinical studies are reasonable. The first question is simply – what is the exposure from Wi-Fi networks? Such exposures to EMF are typically thousands of times less than current safety limits. In fact, one review found:

In all cases, the measured Wi-Fi signal levels were very far below international exposure limits (IEEE C95.1-2005 and ICNIRP) and in nearly all cases far below other RF signals in the same environments.

So not only are exposures from Wi-Fi access points thousands of times less than safety limits, they are also less than the background radio frequency (RF) radiation.

Is there evidence for biological effects on cells? An extensive review of this research concluded:

Overall, there is little evidence of cellular effects of RF fields of health significance below current safety limits.

While they argue for further research in some areas, they were also including cell-phone level exposure, which remember is 100 times that of Wi-Fi, which in turn is no higher than background radiation.

What about electromagnetic hypersensitivity – the reporting of common non-specific symptoms, such as headache, fatigue, dizziness, and confusion, while being exposed to EMF? Well, the same review also summarizes this research, which finds that under blinded conditions there is no such hypersensitivity syndrome. Even with people who consistently report symptoms with exposure to EMF, in blinded conditions they cannot reliably tell if they are being exposed to EMF.

Wi-Fi in Schools

With the research as background, let’s take a look at the current Wi-Fi in school hubbub. News reports indicate:

Some parents in the Barrie, Ont., area say their children are showing a host of symptoms ranging from headaches and dizziness to nausea and even racing heart rates.

The symptoms, which also include memory loss, trouble concentrating, skin rashes, hyperactivity, night sweats and insomnia, have been reported in 14 Ontario schools in Barrie, Bradford, Collingwood, Orillia and Wasaga Beach since the board decided to go wireless, said Palmer.

That is a familiar list of symptoms – non-specific, common and subjective. They are similar to the symptoms that people previously blamed on mold in schools. (But it should be noted that the analogy to mold is not perfect as there is evidence to support the conclusion that some people have a genuine mold allergy, and developed real allergic symptoms to measurable exposures to mold. At the same time, there are those with non-specific symptoms who blame it on mold as the available explanation.)

How do parents know their children are having symptoms secondary to Wi-Fi?

“These kids are getting sick at school but not at home,” he said.

“I’m not saying it’s because of the Wi-Fi because we don’t know yet, but I’ve pretty much eliminated every other possible source.”

I doubt “every other possible source” has been adequately eliminated. That is tough to do for environmental exposures. Further, it should first be determined if there is an actual medical phenomenon, before explanations are sought. One of the primary sources of disconnect between medical professionals and the public is that professionals know from history of published evidence that people can exhibit symptoms without there being a specific physical cause, while the public remains largely unconvinced of this fact. As stated above, even those who had dramatic and consistent symptoms to EMF could not reproduce them under blinded conditions.

Further, the parents are more compelled than they should be at the timing of the symptoms. It should not be that much of a surprise that students are exhibiting non-specific symptoms at school but not home. Stress alone is a sufficient explanation, but there may be others. For example, many students go to school sleep-deprived because they are staying up too late. This is not an issue on weekends and over the summer. Sleep deprivation is a good explanation for most of the symptoms being reported.

There likely is no one answer to what the children are reporting. Once a community has identified a culprit, then many people with non-specific symptoms from any cause are likely to latch onto the available explanation for their symptoms.


Often these issues are framed as a debate over what level of safety is appropriate. There always seem to be those arguing for “zero” risk, or an absolute guarantee of safety. Absolute safety does not exist in our world and is not a reasonable goal. Even with this extreme position aside, it is always easy to argue for greater safety limits than are currently in place. It may always seem reasonable to say that we should err on the side of safety, or wait for further research.

But I do not think this is always the reasonable position. It makes more sense to consider risk vs benefit. In the case of Wi-Fi we have very low biological plausibility given the low levels of exposure, a 1000 fold safety margin with current regulations, no compelling evidence from cell studies of a biological effect, and no clinical evidence of a real health effect.

Meanwhile, convenient internet connectivity is increasingly a vital aspect of our modern lives – certainly in the context of education.

I wonder if those parents arguing against Wi-Fi in the schools, based upon vague anecdotal evidence in the face of low scientific plausibility and lack of evidence of risk, use cell phones. Do they drive, use power tools, have a swimming pool, or snow ski? There are probably hundreds of things we take for granted in our daily lives that have greater risks than Wi-Fi.

These news stories also highlight the need for greater public education in critical thinking. These parents mean well, they are just falling victim to poor critical thinking skills. The news report also indicates that the school board has been largely ignoring them, which is not a good strategy. Professionals and regulators also need to learn how to deal with the public over such issues.

What we have here are the seeds of yet another grassroots movement that is disconnected from science and hostile to authority. This is a scenario we have seen played out many times before, and no doubt we will see it many times again.

39 responses so far

39 thoughts on “Banning Wi-Fi From Schools”

  1. tmac57 says:

    I’ve got an uneasy feeling that if this “Wi-FI is bad” meme gets traction,that we will see pushes to ban them in some communities,and people suing their neighbors that have Wi-Fi ,for making them ‘sick’.

  2. locutusbrg says:

    Maybe we need to stop fighting this logically. Lets call it WiFi therapy and it cures back pain, insomnia, depression, and chronic fatigue syndrome.
    These statements have not been verified by the FDA and are for entertainment purposes only. Call it BrainFi, and sell organic, recycled, wireless G units. They can wear a wrist magnet that helps attract the helpful BrainFi. Why not? good marketing makes a host of dangerous things seem safe and plausible why not do it for a reasonably safe thing so the kids have internet access. Or we can sell the parents a set of 1978 world book encyclopedia’s and they can home school. Either way I get some junk out of my basement. Damn ethics overrated.

  3. CrookedTimber says:

    Sounds like a classic case of mass hysteria feedback loop. As soon as one student reported symptoms the meme was off and running leading to more reports…etc.

    The non-specific symptoms sound to me like too much caffeine and caffeine withdrawal. Maybe someone should see how many Red Bulls and Monster energy drinks the kids consume.

  4. itbrokeoff says:

    In the first paragraph; I think you meant to type mould.

  5. itbrokeoff says:

    Actually, after a fwse search I realise that ‘mold’ is an acceptable spelling in the the States. NM.

  6. superdave says:

    A quick calculation tells me the wave length of G band wi fi is 12.5cm. N band is about half that. This way way above the micro scale, meaning it is unlikely to interact with objects the sizes of cells.

  7. mgerskup says:

    It’s not just the parents, though. There are organizations and people like Magda Havas (quoted in this CBC article fueling the controversy.

    This movement predates Wi-Fi. I’ve seen protests over new cell towers, involving many of the same arguments, and citing many of the same studies. There’s also Lakehead University, which decided to eliminate Wi-Fi a year (I think?) or so ago, for “precautionary reasons”. (

  8. Calli Arcale says:

    I’m not surprised there’s a movement to ban WiFi from a school on this basis. What does surprise me is that it took this long, given the long-standing RF lunacy.

    I would favor banning WiFi from schools on the basis that kids with smartphones or iPads will be able to leech bandwidth off the school, possibly costing the school money by forcing them to upgrade the network to accommodate the traffic. But that’s an entirely different issue, and can of course be solved other ways. Frankly, I’m just impressed the school *has* WiFi, given how many schools are making do with ten-year-old equipment and begging parents for enough toilet paper to go around.

  9. epistudent says:

    The newest boogeyman in my neck of the woods are microwaves.

    Our local power provider has started to install smart meters, and there is a brigade out in force demanding that this practice be stopped. They are convinced that the meters are a deadly source of microwave radiation, and, apparently having never noticed the screen on the front of their microwave door that prevents them from cooking themselves as well as their leftovers, are convinced that microwaves will invade your house and harm your children.

    The concept of a wavelength seems too sensical to try to explain to them, so I don’t really do anything…

  10. “These kids are getting sick at school but not at home,” he said.

    “I’m not saying it’s because of the Wi-Fi because we don’t know yet, but I’ve pretty much eliminated every other possible source.”

    While it may be possible that these people have no wi-fi at home, it is unlikely that none of their neighbors have wi-fi either. Their children are very likely exposed to wi-fi EM when at home.

  11. ccbowers says:

    People seem to have the most irrational fears for things that are invisible, hidden, or very small. Electricity, microwaves, bacteria, molds, “spirits,” wifi, child abductors, odd smells. When you can’t see something… your imagination has to fill in the gaps, and people fill in the gaps with their neurotic fears.

    On the other side, people have an irrational lack of fear when the activity is familiar, such as hopping into a car and driving, which kills 40,000+ a year in the U.S.

  12. mindme says:

    For the longest time my aunt and uncle refused to buy their groceries at a place with a laser scanner. They thought the laser was radioactive and made their food cancerous. My aunt and uncle are not stupid people. Both white collar types. You just never know what fact people are missing, I think.

    I’m somewhat disturbed by the linked article and the total reliance on experts touting the dangers of wifi. CBC is usually pretty good in terms of balance but this really fails.

  13. Daemon says:

    I thought I’d give some background for those not living in Ontario, Canada.

    Barrie is basically the last city before you leave real civilization and hit cottage country. It’s a real city but it does have a bit of a redneck bent.

    Being a small city, it has everything you’d expect one to have: malls, offices, subdivisions and, oh yeah, thorough high speed internet and cell phone coverage. I can almost guarantee that the majority of the complaining parents have several wi-fi networks overlapping their property.

    I wonder if they’ve ever noticed their children passing out of getting sick when they walk into a Chapters or Home Depot.

    My real complaint about a school having a wi-fi network is that the kids will have internet access in the classroom and will inevitably try to abuse that.

  14. Rocket man 36 says:

    Schools also need to learn what exactly critical thinking is. My school started a program that was supposed to teach kids critical thinking skill and they just gave us more math classes. I’m sorry but MATH doesn’t teach critical thinking its just hard.

  15. John Ellis says:

    You might all enjoy this classic Wellington Grey cartoon

  16. TimonT says:

    @locutusbrg – Thanks for the best laugh I’ve had in weeks!

    Is there any reason prople might be more concerned about WiFi than about the radio and TV signals that bombard us constantly? Is it because WiFi signals are higher frequency?

  17. John Ellis says:

    Just remembered, here in the UK this was the subject of crappy journalism by the BBC a few years ago. Ben Goldacre of had an article on it.

  18. HHC says:

    Susan Clarke has a questionable agenda. She equates radio frequencies with mass. The human skull and radio frequency wavelengths are not equivalencies which can be compared. Maybe the groupthink of Ontario kids is that they are sick of their educational school system? Is the router in the schoolroom corner an imaginary villain?

  19. taustin says:

    Perhaps the school should push for criminal prosecution for child endangerment of parents who have cell phones in the home.

  20. Nasikoman says:


    For people who don’t bother to understand how these things work, the simple fact that Wi-Fi has a different name than “radio” is probably enough to give them concern, even though it’s basically the same frequencies as have been “in the air” for nearly a century now.

    “Wi-Fi? What’s that? It carries Internets? *gasp* Does it have MEMES in it?”

  21. daijiyobu says:

    Oh my, I just installed Wi-fi in a school I do IT for!

    Oh, there’s Bob Park in my head, reminding me that the photonic energy of radio waves aren’t strong enough to break chemical bonds and cause DNA mutations

    (e.g. ).


  22. HumanistDad says:

    Dr. Novella, thanks for your timely blog!

    I happen to have direct contact with a member of the Simcoe School Board and I’m going to direct them to your blog post. If they have further questions, I’d like to direct them to you.

    If that’s OK, please email me and I’ll pass your address on to them.


  23. zoe237 says:

    Why would one have insomnia only at school?

    Within the last few months there was a rash of illnesses in a local high school. Memory loss, dizziness, sleepiness, nausea, skin rashes. This was also a brand new school, in which construction continued on one wing. They shut down one wing, had multiple environmental quality tests that showed nothing, and eventually reopened it and said people were imagining it. A few people switched schools.

    And now I know it was because of the wifi. 😛

  24. mindme says:

    Barrie is also a bedroom community for super commuters in the GTA. I would imagine lots of these kids are latch key types waiting for their parents to get home at 8 pm every day.

  25. ColinJagoe says:

    Thanks for this post Dr N. I’m afraid this will start to be more commonly heard about as more and more schools implement wifi. We need more critical thinking like this about the issue. If in fact you can consider it an issue.

  26. scribe999 says:

    I imagine lots of kids throughout the decades have felt sick on Mondays through Fridays during the school year. I know at times I did. Strangely, Friday at 3:00 pm I would always start feeling better.

  27. SARA says:

    I question the number of cases of kids with these symptoms. (at least in the beginning) When you add in the number of kids who will develop the symptoms after all the publicity – cause that’s what “in” right now you no longer have a true number of kids who may have been reporting accurately.

    But the damning problem is that there is a university in Ontario that shut down the wi-fi on campus. The president of the U who made the decision is a biologist. His position was – until its been proven safe, lets just be precautionary since WiFi is a convenience. That sounds sort of reasonable, if you don’t know the evidence. But the problem is – he represents a figure of scientific authority to lots and lots of confused people, who are going to see his action as an indictment on wifi.

  28. Researcher44 says:

    It isn’t the Wi-Fi. Video on CBC shows students in computer lab sitting in each other’s peripheral vision without Cubicle Level Protection.

    Forty years ago designers hired to modernize the business office accidentally discovered that a normal feature in our physiology of sight could cause mental breaks if certain “special circumstances” were created and maintained long enough.

    The office cubicle was designed to deal with the vision startle reflex to stop it by 1968.

    It’s named for that normal feature of physiology, Subliminal Distraction.

    The risk is that one or more of the students will create the same problem at home so that the combined exposure causes the full mental break.

    When my wife had this mental event thirty days after the University of Alabama changed her office eliminating Cubicle Level Protection I discovered it is unknown by anyone in mental health services.

    In seven years searching I find no research about it. No one except designers working with Systems Furniture, cubicles, knows it exists. They see outcomes of only a low level of exposure and believe it is a harmless nuisance.

    VisionAndPsychosis.Net is a seven year investigation of it.

  29. katie says:

    Have any of you googled this Trent prof that is pushing this? Check out her website:

    Conflict of interest much? For a science prof, its really weird that I couldn’t find a way anywhere to apply to her lab as a grad student, she is the only author on almost all her papers, and she only puts out 1-2 peer reviewed papers a year (and from what I could see, they’re not-experimental, mostly case studies).

    This stinks.

  30. Al Morrison says:

    Another great post. Thanks for keeping us Canadians real!

    I think I am going to take on Magda Havas. As Katie pointed out, Havas is no scientist and has much to gain.

  31. eiskrystal says:

    –I imagine lots of kids throughout the decades have felt sick on Mondays through Fridays during the school year. I know at times I did. Strangely, Friday at 3:00 pm I would always start feeling better.–

    Yes, and i’m sure that once one kid got to go home early with such pathetic symptoms, there was no doubt quite an epidemic the next day.

    Tell the kids they will have to lose their mobile phones, computers and tv’s too. Then we will see what happens to this so called effect.

  32. Thomathy says:

    Taking a look at that woman’s website (Magda Havas’s) makes her look like a kook. She is a kook, too. She presents her own published articles as evidence for the existence of the problems she associates with any kind of electromagnetic radiation.

    She has even invented a new type of diabetes. Type 3 diabetes. She claims as evidence for the existence of this disease an analysis of 4 case studies that ‘show’ changes in blood sugar due to exposure to ‘dirty electricity’.

    She even gives advice to people with diabetes and those who know people with diabetes to inform their doctors that they have the condition! What is a doctor going to do with that information?

    This woman is obviously trouble and she is treading a very thin line between being a kook and being culpable for something far worse.

    She has a lot to gain from this publicity. I question her motives here. Her research is obviously itself questionable.

  33. mindme says:

    In Toronto, kids grow up in 40 floor condos. These condos are awash in wifi. I count 9 wifi hotspots on my laptop right now, not including mine. Oddly, doctor offices are not overflowing with Toronto condo kids complaining of these symptoms.

  34. ccrome says:

    Just a quick reference point: GSM Cell phones radiate up to 2 watts at a distance of about 10cm from your brain (for the 1.9 GHz frequency), and 1 watt for the 900 MHz frequency.

    In the 2.4 GHz band, the maximum transmit power allowed by the FCC is 1 watt (+30 dBm). However typical routers transmit at around +15 to +20 dBm, which corresponds to about 0.1 watt.

    So, the maximum theoretical transmit powers are roughly equal, depending on which standards and frequencies you pick.

    However, there’s a huge difference in exposure. A typical phone is, say, 10 cm away from your brain. A typical router is, who knows, maybe 500 cm away? Let’s choose 500 cm for the sake of argument. Even if both the wifi transmitter and cell phone were transmitting at the maximum of 1 watt, the difference in exposure between an average distance of 10cm vs 500 cm would put the signal at 500 cm at 1/2500 the strength of your cell phone. (This calculation is simply (r1/r2)^2 = (10/500)^2 = 0.02^2 = .0004 = 1/2500)

    Feel free to plug in whatever distances you like into the above equation…

    In reality, I believe most routers limit power output to about 1/10th watt, so the exposure difference would be more like 1:25,000 cell:wifi.

    Also, as for the comment that G vs. N have different frequencies, that’s incorrect. Both 802.11 g and 802.11n use the 2.4 GHz band. We do know for sure that these wavelengths (3e8 m/s / 2.4e9 = .12m = 5 inch) *do* interact strongly with water. That’s why microwaves heat up food. Microwave oven’s work at about 2.4 GHz as well, which is why your microwave can knock your wifi networks off the air if your wifi radio is nearby.

    802.11a uses the 5 GHz band, with a wavelength of about 2.5 inches. I don’t know whether these frequencies do much to heat up water efficiently.

  35. mindme says:

    I mentioned the wifi fear to a friend and he remember encountering something about the large number of lawsuits that were filed back when train travel was first introduced. People had never been moved so fast. 30 mph! People were suing railroads claiming such high speeds had dislodged their kidneys etc. I’ve been googling trying to find some kind of reference to that but no luck. Anyone have any idea where to verify this?

    If true, an interesting commentary on how some people panic about new technology. As noted above, sewer gas and grocery store laser scanners proved anxiety. CRTs in offices seemed to be another one back in the 1980s. Of course televisions and microwave ovens unsettled a lot of people.

  36. Calli Arcale says:

    The CRTs aren’t as loony as one might think. Though for most people they’re perfectly fine, a few people can hear them whine, and that can get annoying. If the person happens to also be autistic, it can seriously mess with their day. This is also true of some other electronic devices, with fluorescent lights being another major offender.

    However, the percentage of the population likely to experience anxiety around one of these devices is quite small, and I wouldn’t think it would be sensible to embark on an expensive process of replacing CRTs with LCDs just for them. (And I say that despite being one of those people who *can* hear CRTs.) The main problem with altering the environment to suit a few is that you’ll never be finished; there will always be someone with another problem. So you just find a solution that will fit most, and try to find ways of helping the remainder make do with it.

  37. Chiara says:

    So…here is my ‘critical thinking’ question…. Where are the references to back up your opinion or is your opinion based on extensive research…and not just research but research that has been conducted on children? I would like to find out where any of these opinions on both sides of the spectrum base their statements on. As far as I can tell….these studies on children have yet to be conducted….

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