Not a physicist. However, I'll take a qualitative stab. Radiation that we care about (mostly beta and gamma) is measured in rems, which is essentially a biolog

Not a physicist. However, I'll take a qualitative stab. Radiation that we care about (mostly beta and gamma) is measured in rems, which is essentially a biological statement about how much tissue damage is associated with a certain dose of a specific type of radiation. I assume that WiFi releases no beta particles (electrons), so we're just talking about EM emission: visible light, X-rays, gamma rays, all that fun stuff. Your WiFi equipment is emitting in the microwave spectrum. The energy of photons at these wavelengths is orders of magnitude weaker than the energy of ionizing radiation (essentially gamma radiation). If you don't ionize, then there is no currently known mechanism by which you can cause cellular damage (except via thermal damage ;-) ). If we were to posit the WiFi emitter as a blackbody radiator, it would have to be thousands (millions?) of times hotter than room temperature to have an appreciable emission of gamma radiation thanks to Planck's Law. In other words, I'd guess that 1 banana probably emits as much ionizing radiation as all WiFi emitters have for all time. If you want an unreliable quantitative statement, try this: http://www.timesonline.co.uk/tol/life_and_style/health/features/article665419.ece http://www.timesonline.co.uk/tol/life_and_style/health/featu... (1 year of strong WiFi = 20 minutes on a cell phone - which as far as we know is also 0 rem).