Are my brains being fried?
March 14, 2008 6:11 AM Subscribe
I am sitting two feet from a Cisco Systems wireless access point, model number air-ap1121g-a-k9. Is it frying my brains?
No. Your cell phone shoots out 100x the power when it needs to and it probably sits in a pocket next to your genitals. WIFI is also typically less power than a home cordless phone too. If these items havent killed you or billions of people since the introduction of that technology then I think you'll be okay.
posted by damn dirty ape at 7:05 AM on March 14, 2008
posted by damn dirty ape at 7:05 AM on March 14, 2008
Radiation is not going to be a problem with wifi, its much less intense than your mobile phone. Remember the Inverse Square Law applies so radiation decreases in proportion to the square of the distance from the aerial. Wifi routers won't fry your brian, they will eat your baby though.
posted by tallus at 7:22 AM on March 14, 2008 [1 favorite]
posted by tallus at 7:22 AM on March 14, 2008 [1 favorite]
If you have a 2.4 GHz cordless phone it is subject to the same legal restrictions on transmission power, 1 watt. Most cell phones also emit somewhere just under a watt, varying depending on where you are and what you're doing. But they're not likely to start transmitting 100 watts worth of radio signals - your phone would be as hot as a 100 watt light bulb in that case. Cell phone booster kits typically re-transmit your signal with up to 3 watts of power which is about as much radio power as the average person is likely to get near.
Also, radio waves are non-ionizing - these aren't gamma rays, they're not going to cause cellular damage or anything.
posted by GuyZero at 7:43 AM on March 14, 2008
Also, radio waves are non-ionizing - these aren't gamma rays, they're not going to cause cellular damage or anything.
posted by GuyZero at 7:43 AM on March 14, 2008
Im not talking about legal limits but real power in real devices.
My linksys works at 28 milliwatts max. My cellphone can hit 1-3 watts when it needs to. That's a HUGE difference. My point is that the technologies that we've been living with since at least the late 70s overpower typical wifi implementations.
posted by damn dirty ape at 7:57 AM on March 14, 2008
My linksys works at 28 milliwatts max. My cellphone can hit 1-3 watts when it needs to. That's a HUGE difference. My point is that the technologies that we've been living with since at least the late 70s overpower typical wifi implementations.
posted by damn dirty ape at 7:57 AM on March 14, 2008
Paying attention to anyone who suggests radiation from a wireless router will fry your brains is more likely to fry your brains than the router.
posted by normy at 8:01 AM on March 14, 2008 [3 favorites]
posted by normy at 8:01 AM on March 14, 2008 [3 favorites]
2.4 GHz is non-ionizing radiation. Individual photons do not carry enough energy to disrupt chemical bonds. That means that the only effect it can have on you is heating.
When you're sitting at rest, your brain uses 40-50 watts, and produces that much heat. If it were allowed to remain in the skull, the heat would kill you. So your body gets rid of that heat the same way a car does: with a circulating liquid coolant, to carry the heat away. That's one of the functions of blood, and it is really good at it. Local hotspots are detected and blood flow there increases to improve the cooling.
Most of the radiation from your Cisco router goes in directions other than your brain. Most of what does go towards your brain goes right through and out the other side. If you're absorbing even 10 milliwatts from it, I'd be surprised. What you do absorb is turned to heat. 10 milliwatts is an increase of .02% over the amount of heat already being generated by your brain, which your blood system is already cooling. It doesn't even register.
posted by Class Goat at 8:47 AM on March 14, 2008 [2 favorites]
When you're sitting at rest, your brain uses 40-50 watts, and produces that much heat. If it were allowed to remain in the skull, the heat would kill you. So your body gets rid of that heat the same way a car does: with a circulating liquid coolant, to carry the heat away. That's one of the functions of blood, and it is really good at it. Local hotspots are detected and blood flow there increases to improve the cooling.
Most of the radiation from your Cisco router goes in directions other than your brain. Most of what does go towards your brain goes right through and out the other side. If you're absorbing even 10 milliwatts from it, I'd be surprised. What you do absorb is turned to heat. 10 milliwatts is an increase of .02% over the amount of heat already being generated by your brain, which your blood system is already cooling. It doesn't even register.
posted by Class Goat at 8:47 AM on March 14, 2008 [2 favorites]
Wifi operates at relatively low power, compared to a handheld cell phone, but unlike your phone, it is transmitting all day. I am not aware of any scientific studies that have show damage from WiFi RF, but when I last looked a few years ago, there was one study raising the (remote, unproven) possibility that it could affect the retina.
posted by zippy at 12:53 PM on March 14, 2008
posted by zippy at 12:53 PM on March 14, 2008
The short answer is you're safe.
The medium-length answer is that, as other people have mentioned, the only known mechanism for 2.4GHz radiation to hurt you is by heating your tissue, and the amount of energy you could be absorbing from the WAP is much too small to hurt you.
There is some speculation that there is some other, completely unknown mechanism for harm from GHz-band radiation; but (a) this is either fringe science or pure quackery, depending on who you talk to; (b) multiple studies have failed to find an effect; (c) they're studying much higher power levels (multi-watt cell phones held against your ear).
Longer answer: Cisco describes the AIR-AP1121G-x-K9 as having a maximum transmit power of 100 mW and says it has 2.2dBi antennas, so let's call that about 200mW EIRP if you're sitting in the most intense part of the radiation pattern. Sitting a couple feet from it your head subtends well under a steradian, so you'll get well under (200mW/4π) mW, call that ≪10mW into your head. Or, call it 0.005 mW/cm^2, which is a more useful figure. Googling suggests that your most susceptible organ is your cornea (not much blood flow to carry away excess heat) and that effects start to be seen at around 10 mW/cm^2. So you might be able to give yourself cataracts by running the AP at max power, constantly transmitting, and holding your open eye less than a centimeter from the antenna for a day or so on end. Maybe. (Keep in mind the case of the AP is probably more than a centimeter from the antenna.)
By comparison, a 10W night-light is putting out 100 times as much power as the WAP possibly can, and much of it in the infrared where it'll deposited in a thinner layer of skin/cornea than the 2.4GHz wifi signal.
posted by hattifattener at 12:58 PM on March 14, 2008
The medium-length answer is that, as other people have mentioned, the only known mechanism for 2.4GHz radiation to hurt you is by heating your tissue, and the amount of energy you could be absorbing from the WAP is much too small to hurt you.
There is some speculation that there is some other, completely unknown mechanism for harm from GHz-band radiation; but (a) this is either fringe science or pure quackery, depending on who you talk to; (b) multiple studies have failed to find an effect; (c) they're studying much higher power levels (multi-watt cell phones held against your ear).
Longer answer: Cisco describes the AIR-AP1121G-x-K9 as having a maximum transmit power of 100 mW and says it has 2.2dBi antennas, so let's call that about 200mW EIRP if you're sitting in the most intense part of the radiation pattern. Sitting a couple feet from it your head subtends well under a steradian, so you'll get well under (200mW/4π) mW, call that ≪10mW into your head. Or, call it 0.005 mW/cm^2, which is a more useful figure. Googling suggests that your most susceptible organ is your cornea (not much blood flow to carry away excess heat) and that effects start to be seen at around 10 mW/cm^2. So you might be able to give yourself cataracts by running the AP at max power, constantly transmitting, and holding your open eye less than a centimeter from the antenna for a day or so on end. Maybe. (Keep in mind the case of the AP is probably more than a centimeter from the antenna.)
By comparison, a 10W night-light is putting out 100 times as much power as the WAP possibly can, and much of it in the infrared where it'll deposited in a thinner layer of skin/cornea than the 2.4GHz wifi signal.
posted by hattifattener at 12:58 PM on March 14, 2008
a 10W night-light is putting out 100 times as much power as the WAP possibly can
And you're more likely to get skin cancer fron the good ol' sun than get brain cancer from a wireless access point.
posted by GuyZero at 2:06 PM on March 14, 2008
And you're more likely to get skin cancer fron the good ol' sun than get brain cancer from a wireless access point.
posted by GuyZero at 2:06 PM on March 14, 2008
This thread is closed to new comments.
posted by GuyZero at 6:25 AM on March 14, 2008