Wifi Sector antenna health hazard?

[lutius]

Hi - the building community where I live has just installed a few Wi-Fi ("sector", I believe) antennas and one of them is at same height and facing straight into my apartment. They are probably 10-15 meters across my apartment.
I have a one year old son, and concerned about any health effects this may pose? No expert on this area so any advice will be welcomed. Here are some photos I took. Thanks for teh input.

http://dl.dropbox.com/u/703908/IMG_0162.JPG

http://dl.dropbox.com/u/703908/IMG_0163%282%29.JPG

 

[Pattonias]

Well, you are probably both exposed to Wi-Fi signals all the time, so I don't think this would be particularly harmful.

I know that most people, especially those living in apartments are exposed constantly and I have never heard of anyone being harmed, but then again the cell phone cancer scare is currently under full swing so I imagine wifi is about due. I wouldn't worry about it though. It should be noted that no scientifically validated evidence of sickness due to cell phone signals has been discovered so I wouldn't worry about it.

 

[moegreene9]

I am not aware of any evidence thsa t these antennae are a serious health risk. Much myth and hysteria has grown around these issues but until there is firm evidence one way or another I don't see any point in being scared.

 

[slider142]

Lack of evidence for and against does not constitute an argument for inactivity against a possible danger.
However, an argument using established electromagnetic theory should provide enough information to swing the hypothesis in the correct direction. There is already a thread with good numbers on this particular question here.

 

[Evo]

Lack of evidence for and against does not constitute an argument for inactivity against a possible danger.
However, an argument using established electromagnetic theory should provide enough information to swing the hypothesis in the correct direction. There is already a thread with good numbers on this particular question here.

That's a 4 year old thread and the opinion was that he was off base.

 

[slider142]

That's a 4 year old thread and the opinion was that he was off base.

While the overall opinion is a good indicator, the reason for the link is the information given regarding ionizing radiation and antenna power, which is more relevant than mere opinion, as it gives the OP a starting point for hypothesis and what they should be looking for.

 

[Evo]

While the overall opinion is a good indicator, the reason for the link is the information given regarding ionizing radiation and antenna power, which is more relevant than mere opinion, as it gives the OP a starting point for hypothesis and what they should be looking for.

My point is that the technology has changed, there are varying ways to offer wireless, and there should be updated studies.

Wifi is being broadcast to entire cities now, it is no longer just within/around a building.

I guess a lot of people don't realize that for many years if we couldn't get fiber access into a builing to bring a T3 in, we could send that signal directly into the buidling's fiber MUX.

 

[mugaliens]

Mine comes in via my cable, so it's fairly shielded. Perhaps I should tune down the power of my WAP, as I really don't need it on full power when it's only ten feet from the laptop... Then again, I can take my laptop to the pool without signal degradation, so...

 

[sash]

not to debate the health effects of wifi on the human body
EIRP
dBm mW
17dBm 50mW
20dBm 100mW
24dBm 250mW
27dBm 500mW
30dBm 1Watt
33dBm 2Watt
36dBm 4Watt
39dBm 8Watt
42dBm 12Watt

EIRP = PT - Lc + Ga
where EIRP and PT (power of transmitter) are in dBm, cable losses (Lc) is in dB, and antenna gain (Ga) is expressed in dBi, relative to a (theoretical) isotropic reference antenna
IE 100mW device = 20 dBm
50' LMR400 antenna cable has 3.4 dB loss
20 dB Grid Antenna has 20 dBi gain
The EIRP = 36.6 dBm (20 - 3.4 + 20)

I can not see the sector panel or the radio type but say it a standard sector panel of about 16 dbi and standard outdoor radio of +400mW and say it connected directly to the back of antenna

your EIRP = 26+ 16= 42 dbm or 12 watts ( at close proximity it will give you a bit of a headache)

at 20 meters away through a building you probably will not do much too you.. but a common problem of receiving strong wifi signal is headache and foggy thinking (if you experience this you might consider turning down the radio power a bit...) but this is usually found in setting within a building and close proximity.. I've seen set up with in building where they have 10 dBi antenna and 250mW - 800mW radios and people feeling queezy ( around 2 - 9 watts plus all the combined radios in the room connecting. by regulations your not suppose to have it more then 20 dBm ( 100 mW) per device with in a building.

 

[hamster143]

It's simple physics. Wi-fi EM quanta are not powerful enough to ionise atoms in your body. The only thing they can do is warm your body slightly. You need at least UV to run a risk of any real health hazards.

 

[mugaliens]

It's simple physics. Wi-fi EM quanta are not powerful enough to ionise atoms in your body. The only thing they can do is warm your body slightly. You need at least UV to run a risk of any real health hazards.

You're limited the term "real health hazards" to ionizing radiation. Yet we can easily measure significant brainwave activity, to the point where we're beginning to learn how to allow dismembered people recontrol their limbs (artificial prostheses) using their thought patterns alone.

If you can measure an electrical signal, you can disrupt it. The logical question then becomes, "What sorts of electrical signals might disrupt alpha/beta/delta/gamma brain wave patterns?

These electrical signals are very minute in strength - it doesn't take much to disrupt them! Yet the key is that most of them are, at best, less than 100 Hz in frequency. Thus, if we superimpose a 2.4 GHz signal on top of it, what would it do?

Literally, it would do nothing, at least not to our usual brainwaves, which is why we don't go into convulsions every time the phone rings.

Does this mean our radio frequency spectrum is doing nothing? By no means!

This is personal anecdote, so feel free to discount it. I can talk on my 2.4 GHz handset all day, but I get a dull headache while using a cell phone, and the headache is localized to the area nearest the antenna. If I use it hands-free, I have no problem.

What's going on? I don't know, and frankly don't care, as my solution is to either use it for brief periods of time, to use it hand-free, or not at all.

I'm most concerned with those in the Gamma band, localized in the somatosensory cortx, as that's in the 30-100+ Hz band, right around the area of most power transmissions and motors.

Thus, call me a kook, but I've converted my entire house to DC current...

No, I'm kidding. I do think some people's thinking is befuddled these days, but I sincerely doubt it's due to power transmission, as I live in a sea of power lines (including some 35 kV lines about 1/7th of a mile away), and my thinking is just fine, thank you very much!

 

[sash]

@ mugaliens
"This is personal anecdote, so feel free to discount it. I can talk on my 2.4 GHz handset all day, but I get a dull headache while using a cell phone, and the headache is localized to the area nearest the antenna. If I use it hands-free, I have no problem.

What's going on? I don't know, and frankly don't care, as my solution is to either use it for brief periods of time, to use it hand-free, or not at all."sorry I am not certain if your whole statement is sarcasm or not- but the statement sounds a bit disingenuous here - since you obviously care since you took steps to to avoid or limit cell phone usage.

and really it not hard not to care when you read studies such as - ones like these - http://news.bbc.co.uk/2/hi/health/4113989.stm - where as damage can be seen if one uses cell phone ( and other hand held) for periods longer then 20 minutes, but the body repairs them quite quickly after the call is ended ( 5 min) - unless usage is significantly longer (3hrs)

__________________________
not to debate the physics of it

whether or not it cause permanent health effects is one thing, but whether or not certain body types react to it is another thing. every body is a complex organism and not the identical in every individual , as in it mineral composition.. etc . there are always some variance. I suspect, those who are get headaches, nausea from wifi or Cells, are having some sort of constant sensory inputs to the brain disrupted. ( the condition is called RF hypersensitivity ). Say as in the the inner ear, - the cochlea and the vestibular system. perhaps the the tiny hairs in the cochlea are the right length and/or composition an act as little antennas and begin to vibrate and produce tiny currents. sending confusing signals to the brain which it tries to decipher. which it can not . And that will causes the symptoms of dizziness, nausea, confusion, headaches ... etc . As such what happens when the body alway receives too much stimuli.. Ie flashing cartoons that will cause people to vomit pass out and what have you or the flickering fluorescence lights in office building and the headaches and nausea associated with that. all caused by over stimulation. sure perhaps not long term permanent health effects (such as cancer) but short term quality of life health effects for some --- yes..

everything not always so black and white when it comes to health and well being

heck look when radio first came out and people hearing voices in their heads and the decade they where thought as being crazy.. and it turns out to be loose fillings vibrating to the AM radio waves. or "RADAR hum" which is not an audible sound but actually a "sound " created with in you by standing in a RADAR's field .. all typical phenomenons associated with Electromagnetic radiation and the human body..