Samsung SWC-R640LBAXAR - Manual (Page 189)

Health and Safety Information 184
comfort. They are also required by law in many states if you want to
use your phone while driving.
Cell Phone Accessories that Claim to Shield the Head from
RF Radiation
Because there are no known risks from exposure to RF emissions
from cell phones, there is no reason to believe that accessories which
claim to shield the head from those emissions reduce risks. Some
products that claim to shield the user from RF absorption use special
phone cases, while others involve nothing more than a metallic
accessory attached to the phone. Studies have shown that these
products generally do not work as advertised. Unlike “hands-free”
kits, these so-called “shields” may interfere with proper operation of
the phone. The phone may be forced to boost its power to
compensate, leading to an increase in RF absorption.