Archive for December 31st, 2008

Wifi Allergies


Science, it works.

Science, it works.

Last week walking around Nevada City I viewed a sign for an Alphabioticist. My parents asked me if I knew what that was. I thought about it. I quickly concluded based on my education that I knew of no such title or field and that it sounded fabricated. Of course I am willing to admit I am wrong so I looked it up online. In this case I was right and it is a blending of new age healing and religion (based on my source of Google).

This reminded me of something that I hate: Wifi Allergies.

Some people claim to have a heightened sensitivity to Wifi signals and that implementing programs like city or school wide wifi is detrimental to their health. I know that locally these claims prevented the city wide roll out of free wifi in Sebastopol

It is simply ridiculous. As a student of physics I find the ignorance of such claims appalling. Wifi radiation is the same radiation emitted by the sun, the earth, radios and even people. Wifi is between radio and infrared radiation, we are constantly exposed to radio emissions and are our bodies constantly produce infrared radiation. 

If someone was sensitive to electromagnetic radiation then they would suffer greatly from everything around them, sunlight and radios. Instead they are sensitive to just a particular band of radiation that of 2.4GHz or 5.0 GHz (depending on the wifi settings). I am assuming that they cannot be allergic to 2.4GHz as then they would also feel the same affects from cordless phones which operate at 2.4GHz.

Near the 2.4GHz band is the frequency used by microwave ovens: 2.45GHz. This may worry some but if we were directly exposed to this radiation we would just warm up like food in a microwave oven. The oven operates by thermally exciting water molecules so they vibrate and produce heat. So wifi at 2.4GHz is not effecting people.

This leaves the 5.0GHz band. Energy of high enough energy can hurt people, UV radiation and above causes skin cancer by altering the DNA in skin cells. But 5.0GHz is 100,000 times lower in energy then radiation produced by the body. It could excite a molecule similar to the way water is excited at 2.45GHz however this is vibrational energy and would just warm up the molecule. It does not have enough energy to break chemical bonds (which is roughly 1eV or visible light).

Claiming to be allergic to wifi without also being sensitive to the myriad other sources of electromagnetic radiation is unfounded and should not be taken into account when discussing development of large scale wifi plans.

Read Full Post »