I once had the opportunity to listen to an extremely talented WiFi expert from Aruba Networks explain on a whiteboard to a rapt audience of infrastructure engineers how this works. And how adding multiple SSIDs is a contributing factor to this problem.
The most fascinating piece was what he called the "butter factor". The closer a substance is in consistency to butter, the more it will absorb WiFi signals. Aruba had one heck of a challenge installing a WiFi network in the Land O'Lakes manufacturing facilities. They had to use directional antennae mounted mounted at eye level down each aisle of the factory.
Agreed. The primary concern is tissue heating that cannot be sufficiently dissipated. This is nearly impossible at "wifi" power levels(Below 1 watt) without carefully contrived situations -- such as placing your eyeball(which is the least-equipped organ to dissipate heat) at the exact focal point of a specially designed parabolic dish.
I have been safely working around thousands of watts of RF power for 20+ years and have maintained my 20/15 vision.
The most fascinating piece was what he called the "butter factor". The closer a substance is in consistency to butter, the more it will absorb WiFi signals. Aruba had one heck of a challenge installing a WiFi network in the Land O'Lakes manufacturing facilities. They had to use directional antennae mounted mounted at eye level down each aisle of the factory.