This is an excellent question that I am sure many parents are concerned about with their children’s safety! Indeed, the word “radiation” is used around quite a lot these days, especially by the media in an alerting and dangerous context (i.e. Fukushima disaster nuclear radiation, or cancerous sunlight UV radiation). In reality, radiation is a general scientific term that covers an enormous spectrum: from X-ray and nuclear radiation, down to radio and Wi-Fi waves, and even visible light! What we consider to be dangerous radiation is called “ionizing radiation”, that is, radiation that has enough energy to alter molecular function and structure. This class of radiation covers things like X-rays, nuclear (gamma) radiation, and even some high-energy ultraviolet (UV) radiation (like those from the Sun). Ionizing radiation can cause cancer or burns. Everything else, however, from visible light to microwaves to radio waves, is in the class of “non-ionizing radiation.” The radiation from these sources does not have enough energy to physically or chemically damage at the molecular-scale. Under the most extreme exposure to this radiation, the most that could happen is that heat is generated. Wi-Fi belongs to the RF radiation spectrum, which falls under non-ionizing radiation. In addition, the energy that visible light carries is much greater (~1 trillion times) than that of RF radiation, so simply walking outside on a sunny day will expose you to more radiation than any wireless network can put out.

There was a study performed at Princeton University in 2007 that reported Wi-Fi radiation at their university (link at the end). The study itself also cites recent literature from the past decade that documented Wi-Fi and RF exposure safety levels. In their report, Princeton found that the effect from wireless networks was so low that it was nearly below their measurement detection limit (<<1% of the maximum recommended exposure to RF radiation). They concluded that Wi-Fi radiation (and generally RF radiation from wireless networks) is nearly negligible compared to environmental sources that there should be no concern over health and safety. This study is consistent with the myriad of studies performed on cell phones that still fail to conclusively link cell phone radiation to cancer, despite the source of that RF radiation being held less than an inch away from the head or the brain.

So, in conclusion, you should have nothing to worry about. Wireless networks emit so little radiation compared to other sources that there are no harmful effects associated with Wi-Fi.

This is a tough question. What I would say is the following:

Wi-Fi uses high frequency radio waves, meaning signals that run at around 2.6GHz. This corresponds to a wavelength of about 10cm, which is much, much larger than the size of the DNA molecules in our body (about 2.5 nanometers, or 0.00000025cm). Why do I mention DNA? Because many cancers develop from damage to DNA. If a DNA molecule encounters a radio wave, the radio wave only carries enough energy to warm up the DNA, not to break any bonds, which is what is required for really damaging the DNA in a way to cause cancer. That's why XRays (wavelength ~10 nanometers) are so bad -- because their wavelengths are a lot more comparable in size to DNA molecules, and XRays carry a lot more energy, enough to break bonds and damage DNA.

Furthermore, the sun emits much higher amounts of higher frequency radiation (like UV and XRays) than a Wi-Fi router emits of the high frequency radio waves even if your head is right next to the router. Usually we don't keep our heads right next to a router, and I believe that in the Santa Barbara area, people tend to catch some sun now and then :)

There is no reason that I know of to believe that Wi Fi poses any threat to the health of humans or animals. Now of course scientists don't know everything and that's why the world health organization (and probably many other people) are doing studies looking for health problems that may be linked to Wi FRi or cell phone radiation and as far as I know they haven't found anything.

UV radiation has a frequency that is a million times greater than Wi Fi signal and this makes a big difference. Wi Fi is much, much less dangerous that UV radiation both because of the great difference in frequency and because the amount of radiation is so small compared to what we are exposed to by the sun. I don't know of any reason to associate Wi Fi radiation with smoking.

I did some searching online for research showing harmful effects of Wi Fi. The only claims I found that Wi Fi had harmful effects was from people selling products which seem to have no scientific merits.

I hope this helps some. Best of luck.

I'm 100% sure there is nothing to worry about. WiFi/radio waves, microwaves, visible light, UV, and X-rays are all types of electromagnetic radiation, they only difference between them is the energy, which increases with the frequency. While the higher energy types of radiation can be harmful, microwaves and radio waves have less energy than visible light. The main effect that they could have on the body is that they can heat things like in a microwave oven, but the intensity of the radiation from WiFi routers is of course nowhere near that so it's of no consequence. There have been studies looking at more subtle non-heating effects, but mostly for things like cellphones held up to your ear and radiation from power lines which are much more intense than WiFi. (In fact radiation from cellphone towers which everyone is exposed to is probably a similar intensity as from a WiFi router.) Even for these, the consensus is that they're not harmful. It's important to note that when scientists are trying to determine whether something causes some very small health effect, even if the effect doesn't exist a few studies may come to the conclusion that it does, just because of statistics and luck. So we have to look at many large studies and go with the preponderance of evidence.

Source:
electromagnetic radiation