I got an EM meter today after the results of that state-funded cancer study were pretty concerning. Checked out the house and I’m not worried. The EM radiation from the WiFi access point drops to unmeasurable in about 3-4 meters distance. The Hue base station emits considerably less radiation than the AP. The bulbs emit about 1/3 of what the base station does. The frequency of the transmissions seems to have to do with the individual bulb’s position within the mesh network. One of the bulbs seems to be a central node and that one transmits pretty much permanently, albeit at a low transmit power. The EM meter only picks it up to about 50cm distance. The other bulbs transmit short bursts every 3-4 seconds, so overall, that’s perhaps about 15 seconds per minute. So they’re idle for 3/4 of the time. The Hue White and Ambiance bulbs seem to be transmitting less than the color version.
The main factor for radiation at our home is the mobile phones. Even if only WiFi is on, they seem to emit the same amount of radiation as the access point (almost 100mw) and we pretty much constantly hold them in our hands.
Oh, and the ZWave bulbs transmit drastically less and at much lower TX power than the Hue bulbs.
The EM meter only covers the 800 - 2500 MHz band, so I can’t sad how other things (like LED bulbs etc.) behave. It’s also not the most expensive model, but it’s relatively accurate I believe.