Networking & wireless forum: Wi-fi. Are there any health risks?

FDA link on radio frequency (RF) radiation:
http://www.fda.gov/cellphones/qa.html

Even if there was, there isn't much you can do about it aside from moving to a cave. TV/Radio/Cellular/Cordless phones and the other thousands of transmitters wouldn't disappear overnight. If you're still worried, move the AP at least a meter away from you, the power level at 1 meter drops by a power of 10,000.

The wireless router offers no danger.

Routers radiate approximately 1 watt.

When you pass a full power AM broadcast station you are being exposed to 50,000 watts.

Many amateur radio hobbyist radiate 1000 watts.

Shipboard environments exceed 1,000,000 pulsed watts.

All decrease at 1/(R x R)[R = the distance from the router], so the further away you are from the antenna (R) the lower the RF intensity.

I haven't included the increase in intensity antennas can create.

The belief that a wireless router's radiation is dangerous is unfounded and entirely false.

The output of a wifi card or access point is generally a couple hundred milliwatts, which is no where near 1-watt. [Also, 50,000 watts is the maximum for a broadcast radio station (most are 5,000 to 20,000 watts, very few are 50,000) and 1,000 is also the maximum for an amateur radio station, most are more like 200 watts on HF or 1 to 20 watts UHF).

But the point, really, is that an access point or wifi card is considered to be safely low powered and is also at a reasonable distance. Consider a cell phone, which has similar power outputs (a few hundred milliwatts ... a few tenths of a watt). Most are operated less than 2 inches from your head. In my view, regulations and scientific findings not withstanding, that is cause for concern for people who use a cell phone hours and hours per day. But at 3 feet, the exposure to a wifi WAP of the same power is less than one 200th of the exposure from the cell phone at two inches, just due to the distance. And if that number becomes 5 feet, it's one 900th. So distance is your friend here, the power output is low, but once you are even a few feet away, it's the distance, coupled with the low power, that keeps your actual exposure very low. I'd be much more worried about the cell phone that is on your belt holster constantly and 2" from your brain when in use. [Cell phones are transmitting and emitting radiation even when they are not in use, although not continuously].

You missed the frequency of the energy and the directivity of the antenna.

The technical comment about the distance from the router is what makes the point that a router is not a dangerous thing.

Anyone that uses a cell phone on a regular basis has far more to worry about than a wireless router or cordless phone. I don't think I would sleep with it under my pillow though.

Your writing this statement, "The belief that a wireless router's radiation is dangerous is unfounded and entirely false." is simply egotism and ignorance. To say "entirely False" without huge data to back you up is ridiculous!

The simple observation is to note that the frequency of a router is pretty much what comes out of your Microwave Oven! Now I know you would not put your head in the microwave so don't try to convince others to do so! Their suffering would be on you hands.

Joe

http://en.wikipedia.org/wiki/Microwave says (I didn't check elsewhere, however) that
- your router uses a 2.4 Ghz signal
- your magnetron uses a 2.45 Ghz signal

But the power is different. It's not advised to go sitting into a magnetron oven and boil yourself. While there seem to be very few negative effects of being somewhere where there's wireless.
We have it all over the building at work for at least a year and nobody yet died. I don't even think that anybody got ill due to it. Neither did I read about a significant increase of illness for Starbucks employees compared with non-WiFi coffee shops.

Kees

You said that when you pass a full power AM radio broadcast station you are being exposed to 50,000 watts. But are those watts from microwave energy?

While the increase in technology on our little floating orb is increasing the radiation exposure of us all, the background radiation is much more intense. Granted, we are adding to the rads we pick up, you are going to die from something!

In Europe, the cell phones are designed differently, so that the radiation towards the ear is reduced a lot. There are a couple companies, like BioPro and Advanced Tachyon Tech, which sell small round disks that are affixed to the outside of the phone. I have both on my cell phone, as a hedge. Microwave radiation like that from an microwave oven (aka ''radar'' oven) oven are banned in some countries. WRT to radiation coming in from the galaxy, I would think that part of the evolutionary process would've tweaked us to survive while bathed in some kinds of ''natural'' radiation. BTW, we here in the US get corporate science not real science. Real science still openly exists in some countries where politicians listen to their science advisors. Bottom line: cell phones and micros are not as harmless as we're told they are. Some people get the bluetooth headset which works with bluetooth enabled cell phones. This allows you to keep that antenna on the cell phone a few feet away from your head. Also if you must use a microwave oven, always keep some distance between it and yourself, at least six feet. If its door becomes warped, junk it.

100mW (20dBm) isn't the legal limit. The limit is actually based on your EIRP, which is the transmitter and antenna combination. 4W (36dBm) is the limit for non-point-to-point communication. An example of 200mW (23dBm) card attached to a 15dBi omni antenna after losing a couple dB in cabling and connectors sits you right at the limit. 23 - 2 + 15 = 36.

There are several posts that say there is no hazard, and they are correct!

People who become worried about non-hazardous things because of articles in magazines, etc, can fall victim to those who would sell absurdly worthless gizmos at high prices to ward off, prevent, or otherwise negate the mythological hazard.

Enjoy the benefits of your wireless connectivity and forget the health hazard scare nonsense!

Want to try something interesting?

I have a Linksys WRT54G, with third-party firmware that lets me boost the power output somewhat. I also have high-gain antennae hooked to it.

A foot away is a dual-cassete deck with a turntable (yes, it's old. I use it to dub my folks' old stuff to CD for them). It's hooked up to the sound card of the computer underneath it (the deck and router are on a hutch).

If I switch the deck to tape mode and listen... you can hear little pings and pulses, several every second in bursts. At first, I thought this was being introduced through cables, but then I realized that it only happens in tape mode, and not phono mode.

Also, if I disable the router's radio, it stops.

Conclusion: That noise - presumably the beacon signal from the router - is being picked up magnetically, rather than electrically. By the tape deck heads.

You'd be much better off worrying about heart disease -- it's the number one cause of death in the US and most of Europe. They order: cardiovascular disease, cancer, Alzheimer's Disease and accident (in that order). Alzheimer's victims usually die of pneumonia, a lung condition or a cerebrovascular condition -- so Alzheimer's victims are often declared to die of other causes. Watch out for motorcycles and cars -- very dangerous!

I've found that plugging my cordless phone and wireless router into a hifi grade mains extension helps to reduce the negativity of the radiation.