NPR did a cell phone piece, today. Apparently, cell phone providers are supposed to be very up front about the amount of radiofrequency radiation their products emit, as expressed by Specific Absorption Rate, or SAR, values.
I've owned about six different cell phones and not once were the SAR values ever brought up to me.
Anyway, I went hunting for the information and found a search tool at
https://gullfoss2.fcc.gov/prod/oet/cf/eas/reports/GenericSearch.cfm.First, find the FCC ID number of your cell phone. Mine is located under the battery but yours may be elsewhere on your phone.
Then, in the top two boxes, enter your FCC ID number (the first three characters go in the first box and the rest of the characters go in the second box).
Scroll down to the bottom and click "start search."
That should take you to a page of document listings. Open the document(s) and look for "...the section on SAR compliance, certification of compliance with FCC rules for RF exposure, or similar language. This section should contain the value(s) for typical or maximum SAR for your phone."
According to
http://www.fcc.gov/oet/rfsafety/, "the FCC limit for public exposure from cellular telephones is an SAR level of 1.6 watts per kilogram (1.6 W/kg)."
For more, including whether or not earpieces reduce RF exposure, go to
http://www.fcc.gov/oet/rfsafety/rf-faqs.html.