[metrokoi]

Of course. Although if one couldn't walk/crawl a few feet out of a bedroom for an emergency, they are probably unconscious or have a very large bedroom. I'm assuming the marketed consumer would have minimal usage of a cell phone anyway if they are concerned about electromagnetic radiation.

[AstralStorm]

I was thinking more of a whole living space. It's actually not that bad if you have a phone within a walking distance and the area is safe.

But then it's more about self discipline. You can always shut down the devices yourself instead of relying on a curtain measure for that which might prove annoying.