Why you shouldn't worry about radiation from your Wi-Fi router or iPhone

First and foremost, RF radiation is not the same as ionizing radiation generated by decay of radioactive isotopes, and from the sun itself. This isn't Radiation Physics 101 in 1000 words, so in short, RF lacks the energy that ionizing radiation has to break chemical bonds, ionize atoms, and damage DNA.

Sufficiently high levels of RF radiation can heat tissue and could theoretically cause tissue damage. But, these levels aren't reachable by the public, assuming safety standards are maintained, and the only people that need to be worried about them are generally workers in extremely close proximity to a transmitter.

Without delving into a basic physics lesson about time, distance, shielding, and wavelengths, that microwave in your kitchen is probably 700W. It is focused on the area below the emitter, and shielded by the microwave's structure itself.