'Few people know that there are federal safety limits for exposure to the weak radiation emitted by cellphones and other wireless devices. There often is language about this embedded right in our phones, but finding it requires knowing where to look, wading through several steps and then making sense of the technical jargon.
Concerned about the lack of public awareness, Berkeley, California passed a law in 2015 calling for cellphone stores to post warning signs. The signs caution that if you carry a phone in a pocket or tucked into a bra when the device is on, “you may exceed the federal guidelines for exposure’’ to radio-frequency radiation.'
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