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http://www.ottawacitizen.com/health...owers+kept+away+from+homes/3780588/story.html
Edit: If anyone can find the actual NRC Press report please post the link.
New study warns of risks from emissions, suggests towers be kept away from homes
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Cell towers don't use "hundreds of watts" of transmission power. In most cases, it's well under 50 watts.
Nonetheless it's true that RF emission sources are increasing around us. That "smart meter" on the side of your house? Yep...it's got a transmitter in it.
Nonetheless it's true that RF emission sources are increasing around us. That "smart meter" on the side of your house? Yep...it's got a transmitter in it.
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Thanks SharpNFuzzy. I found the link on the NRC website too.
http://article.pubs.nrc-cnrc.gc.ca/...&journal=er&volume=18&articleFile=a10-018.pdf
http://article.pubs.nrc-cnrc.gc.ca/...&journal=er&volume=18&articleFile=a10-018.pdf
I wouldn't say they are crackpots, but the kind of symptoms they are describing are so varied and random (not to mention anecdotal) that I don't think any real conclusions can be drawn. They pretty much admit the same thing. About the conclusions I mean.
The article I linked to was specifically directed at the cancer scare from cell phones and towers. Could they be having an effect on our bodies in other ways via some unknown mechanism? Maybe. Maybe not. It would be impossible to say until they discover what that mechanism would be.
The fact that people haven't been dropping dead while living near power stations and radio/TV transmitters for all these years is of some comfort to me.
It's also getting a little late to try and put the cell phone genie back in its bottle. Moving cell phone towers away from where people live would pretty much mean that every populated area would be a cell phone dead zone, would it not? How many people would be happy about that?
The article I linked to was specifically directed at the cancer scare from cell phones and towers. Could they be having an effect on our bodies in other ways via some unknown mechanism? Maybe. Maybe not. It would be impossible to say until they discover what that mechanism would be.
The fact that people haven't been dropping dead while living near power stations and radio/TV transmitters for all these years is of some comfort to me.
It's also getting a little late to try and put the cell phone genie back in its bottle. Moving cell phone towers away from where people live would pretty much mean that every populated area would be a cell phone dead zone, would it not? How many people would be happy about that?
The NRC article is claiming that the Russian description of microwave radiation sickness may have merit, and that the current anecdotal reports of symptoms match that of microwave radiation sickness. They're not talking about cancer, which is what the other web site was talking about.
RF radiation decreases at the square of the distance from the source. Cell tower 50W, people generally many metres away. Cell phone power generally 1W (GSM peaks at 2W typically) but a few cm's away. The cell phone is worse. Granted, it isn't continuous (well, for some people it nearly is) but it puts things in perspective. As far as the article goes, anecdotal evidence is NOT evidence; at best it is an incentive to do real analytical research.
This study is peer reviewed and more of a meta study so I wouldn't question it because the NRC is now for profit. What journal isn't?
The writer of the report seems pretty even keel and has recommended safe distances and heights.
My question is does Industry Canada have any "recommended safe distances and heights" for these towers in Canada and have they been enshrined in law.
After our pirate radio discussion last year, its clear that these things can be dangerous, its just a question of proximity.
The writer of the report seems pretty even keel and has recommended safe distances and heights.
My question is does Industry Canada have any "recommended safe distances and heights" for these towers in Canada and have they been enshrined in law.
After our pirate radio discussion last year, its clear that these things can be dangerous, its just a question of proximity.
I had a quick look at the report which seems to be a review of the literature on the subject and not a report of any new findings. Radio energy is just that, energy, so it has the potential to affect the human body. So far, no researcher has established exactly what radio frequency energy does to humans at typical exposure levels in day to day life.
Billions of people use cell phones every day but we have yet to see any definitive links to human illness. Cell phones have been in use since the mid-1985s with widespread use for at least the last 10 years on a global basis. Like this recent review, it seems that everything written includes anecdotal evidence and suggestions of possible issues. No researcher seems to be able to link specifical negative health consequences with levels and duration of exposure and the number of individuals per thousand who would be affected.
Suppose for a moment that a link was found between environmental radio exposure and human health. How bad would the health issue have to be for people to accept complete or partial shutdown of radio systems, or restrictions on use? Bluetooth, computer wireless links of all kinds and cellular would be restricted. What is the threshold? Would we shutdown radio systems if 10 people died per year? 100 or 1000? What if 10% of the population was affected but the symptoms were so slight that only a very sensitive test could reveal them? If we are going to restrict radio systems because of potential ill effects then what should we be doing about proven hazard to public health like automobiles?
The economic consequences of curtailing radio usage would be enormous. Wireless communications of all kinds have become an integral part of business and social life. Huge amounts are spent each year on service and equipment which provides employment for 10s of thousands of people in this country alone.
Finally, if you really want to do something about electromagnetic spectrum hazards, wear sunscreen. The link between sun exposure and skin cancer is well proven and highly preventable.
Billions of people use cell phones every day but we have yet to see any definitive links to human illness. Cell phones have been in use since the mid-1985s with widespread use for at least the last 10 years on a global basis. Like this recent review, it seems that everything written includes anecdotal evidence and suggestions of possible issues. No researcher seems to be able to link specifical negative health consequences with levels and duration of exposure and the number of individuals per thousand who would be affected.
Suppose for a moment that a link was found between environmental radio exposure and human health. How bad would the health issue have to be for people to accept complete or partial shutdown of radio systems, or restrictions on use? Bluetooth, computer wireless links of all kinds and cellular would be restricted. What is the threshold? Would we shutdown radio systems if 10 people died per year? 100 or 1000? What if 10% of the population was affected but the symptoms were so slight that only a very sensitive test could reveal them? If we are going to restrict radio systems because of potential ill effects then what should we be doing about proven hazard to public health like automobiles?
The economic consequences of curtailing radio usage would be enormous. Wireless communications of all kinds have become an integral part of business and social life. Huge amounts are spent each year on service and equipment which provides employment for 10s of thousands of people in this country alone.
Finally, if you really want to do something about electromagnetic spectrum hazards, wear sunscreen. The link between sun exposure and skin cancer is well proven and highly preventable.
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I haven't read the article, but most of you have missed a point here. A cell phone tower (base station) does not only transmit on the cellular frequencies, but also on microwave via the microwave dishes for the backhaul. The dishes are directional and such there should be little stray RF energy going elsewhere except to the other dish far far away, but it is still possible there is some stray energy that is radiated to nearby area.
If the study is about microwave, then this is the microwave energy that I will be thinking of. No cellphones today utilize microwave frequency range (1.9GHz is close but not microwave yet).
Your home microwave oven operates in the 2.3GHz spectrum (close to the WiFi / ISM 2.4GHz one), as a comparison.
What RF energy is dangerous or not, depends on many factors, the intensity of the energy, and possibly the frequency but so far science is far from a consensus. Yes, I have been following this bit since the 80's myself.
If the study is about microwave, then this is the microwave energy that I will be thinking of. No cellphones today utilize microwave frequency range (1.9GHz is close but not microwave yet).
Your home microwave oven operates in the 2.3GHz spectrum (close to the WiFi / ISM 2.4GHz one), as a comparison.
What RF energy is dangerous or not, depends on many factors, the intensity of the energy, and possibly the frequency but so far science is far from a consensus. Yes, I have been following this bit since the 80's myself.
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^^^^
The microwave links don't run that much power and are focused into a beam by a parabolic antenna Also, "microwave" is an arbitrary term, usually meaning frequencies above 1 GHz. There won't be much of a difference in characteristics between a signal at 1.9 GHz and 2.4, other than frequency.
The microwave links don't run that much power and are focused into a beam by a parabolic antenna Also, "microwave" is an arbitrary term, usually meaning frequencies above 1 GHz. There won't be much of a difference in characteristics between a signal at 1.9 GHz and 2.4, other than frequency.
Microwave links are not hazardous to the public because of the restrictions imposed by safety code 6. All the radio energy sources are taken into account when making this calculation. As you can imagine it gets really complicated for locations like the CN Tower with dozens of transmitters and the requirement to determine exposure levels on nearby buildings. There are meters to measure RF exposure to ensure that the calculations reflect reality. The safety code 6 calculations are required as part of the licensing process and periodic site surveys with a meter may be required.
That said, the area in front of a microwave dish can be hazardous because the energy is focused into a small area just like light in front of a flashlight. The effective radiated power in the main beam of the antenna can be in the kilowatt range. Microwave antennas are usually located where public access is not available like the top of a tower or the roof of a building. If the safety code 6 calculations show that RF energy levels exceed code where a person might go then signs and physical barriers may be required.
The world has been dealing with microwave energy for over 60 years so the health issues are generally understood. Safety codes exist that protect the general population from casual exposure and workers from occupational exposure.
That said, the area in front of a microwave dish can be hazardous because the energy is focused into a small area just like light in front of a flashlight. The effective radiated power in the main beam of the antenna can be in the kilowatt range. Microwave antennas are usually located where public access is not available like the top of a tower or the roof of a building. If the safety code 6 calculations show that RF energy levels exceed code where a person might go then signs and physical barriers may be required.
The world has been dealing with microwave energy for over 60 years so the health issues are generally understood. Safety codes exist that protect the general population from casual exposure and workers from occupational exposure.
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^^^^
On the microwave level of the CN Tower, the space behind the microwave dishes is shielded, with warning signs on access doors to where the antennas are (behind that huge white "donut"). Also, the telecom office up there, where I'd occasionally go to do some work, was inside a Faraday cage. When the CBC built their building on Front St. W., across from the CN Tower, they had to install a lot of shielding to prevent interference.
BTW, work with microwaves actually (slightly) predates WW2. Many of the WW2 radars used microwave frequencies even back then. It was the British invention of the http://en.wikipedia.org/wiki/Magnetron that made those radars possible.
On the microwave level of the CN Tower, the space behind the microwave dishes is shielded, with warning signs on access doors to where the antennas are (behind that huge white "donut"). Also, the telecom office up there, where I'd occasionally go to do some work, was inside a Faraday cage. When the CBC built their building on Front St. W., across from the CN Tower, they had to install a lot of shielding to prevent interference.
BTW, work with microwaves actually (slightly) predates WW2. Many of the WW2 radars used microwave frequencies even back then. It was the British invention of the http://en.wikipedia.org/wiki/Magnetron that made those radars possible.
I went looking for the safety code because i thought it might be relavent to the discussion here, but i see it was revised in 2009 and health canada has it for sale, not for download. The 1999 version is available for download from other sites.
Safety code 6, published by health Canada isn't law itself. But since it has been referenced in MOL court procedings, it has become the law of the land.
It would be interesting to see what the differences are between the 1999 and 2009 versions.
Inseresting to note that the new version comes with "Technical Guide for Interpretation and Compliance~" that sounds like a CYA.
http://www.hc-sc.gc.ca/ewh-semt/pubs/radiation/radio_guide-lignes_direct-eng.php
Safety code 6, published by health Canada isn't law itself. But since it has been referenced in MOL court procedings, it has become the law of the land.
It would be interesting to see what the differences are between the 1999 and 2009 versions.
Inseresting to note that the new version comes with "Technical Guide for Interpretation and Compliance~" that sounds like a CYA.
http://www.hc-sc.gc.ca/ewh-semt/pubs/radiation/radio_guide-lignes_direct-eng.php
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