Crim Liar is right. People are scared by the word radiation, but it is everywhere. Literally everything you see is blasting you with radiation, in the form of visable light. Other things that emit radiation include, the screen you're reading this on, the radio waves the give you misic. The TV signals you watch, light bulbs, video game controllers, and television remotes. Radiation is everywhere and is fine. What is dangerous is high energy radiation called ionizing radiation. This includes infrared, xrays and gamma rays. Infrared frequency starts at about 300Ghz. Compare to your measly wifi signal that 2.4 or 5ghz. To compare the wavelenghts, 5ghz wifi is about 60millimeters and infrereds 300ghz is about 1mm. Now you may not know what the last bit of info here means but it is illustration the specific numbers in these types of radiation and their energies. The most interesting thing about the difference here is what occurs between those two frequencies, visible light. So that means that the lightbulb above your head is exposing you to higher energy radiation than that little wifi extender in the hall.