Comment by perlgeek

Non-ionizing radio waves are generally safe for humans.

The only mechanism besides ionization that could harm humans is through the transfer of lots of power into the human body (think soldiers keeping themselves warm by stepping in front of a radar emitter).

So let's try to do a ballpark estimate of how much that could matter.

I haven't found (from a quick search) any data regarding the transmission power, but the data sheet at https://fcc.report/FCC-ID/2AD56HLK-LD2410B-P/6620025.pdf says the average current consumption is 79mA at 5V, which means it uses 0.4W.

How much of that is actually transmitted? I'd guess 10%-50% (likely much less, but let's go with this more conservative estimate, from a safety perspective), so now we're in the range of 40mW to 200mW.

If you absorb 1/4th of that (again, somewhat conservative estimate; you'll likely also reflect some, and most of it is going to pass you), we're at 10mW to 50mW extra power that is absorbed by your tissue.

Again, this is a super high (and thus for our purpose, conservative) estimate. Somebody else in this thread mentioned microwatts being absorbed, which sounds much more plausible.

To put this into context, the base level of power that an adult human operates on at rest is about 100W. This is a factor of 500 to 2500 more than the power absorbed from our millimeter wave radar. Unless all the absorption happens by a very specific and sensitive part of the body (like your eyes or so), this should just be background noise.

If you want another perspective, you could try to compare it with whatever radiation (both RF and heat) that your phone emits, that you likely carry in your pocket for hours at a time.