Any radiation around visable light (which is ven more dangerous than IR LED's) and higher around EHF becomes ionizing radation so it pays to make sure it's safe Ionizing radiation does split DNA, why do you think x-ray workers wear lead and leave a lead lined room?

At minimal amounts (milliwatts) of EHF radiation is dangerous, unlike microwave ovens at 2.4Ghz that need some few hundred watts to started getting water molecules excited.

BUT the MED thing.... if it's a radio transmitting or electronic device which it is and being designed for use as, also means you're required to get a license to manfacture such equipment by law, simple as that (or think of it as an approval, all appliances including your stereo have one). Maybe the end user won't need a license to operate this (approved device) but the manufacture still has to obtain a license to create it, to prove it won't cause interfernce with other spectrum license holders elsewhere, that it doesn't give off dangerous amounts of radiation, unwated or spurious transmissions in the same or other bands, that can't effect other electronic devices, (there are some important one's like pace makers you know, and experimenting can be dangerous in this sense if your neighbour, who you until now forgot lived next door, may have one).

Cheers,
Gavin.