> A Federal standard (21 CFR 1030.10) limits the amount of microwaves that can leak from an oven throughout its lifetime to 5 milliwatts (mW) of microwave radiation per square centimeter at approximately 2 inches from the oven surface.
So you were off by a factor of 200, and you can see that my referencing -40dB of attenuation was an underestimate. I do wonder what details it was that you thought you might recall.
Quite disappointed by HN standards of self-moderation yet again.
You’re way off, that’s 5 milliwatts per square cm times the surface area.
A 1 foot cube, has 6 faces of ~30 cm * 30 cm or 5,400 cm2. 5,400cm2 * 5mw = 27 watts. Of course 2 inches from the surface is a significantly larger box.
Of course that’s a legal maximum, most devices should be well below it.
Sunlight is 93w/square foot, this would be under 4.5w/square foot good luck melting something at room temperature with that. I think you have a poor intuition about the difference between point sources and energy across an area.
Anyway, math is math but presumably this is why that’s the legal limit. It’s low enough to be safe while high enough not to be expensive for manufactures.