86Do wireless phone accessories that claim to shieldthe head from RF radiation work?Since there are no known risks from exposure to RF emissions fromwireless phones, there is no reason to believe that accessories thatclaim to shield the head from those emissions reduce risks. Someproducts that claim to shield the user from RF absorption use specialphone cases, while others involve nothing more than a metallicaccessory attached to the phone. Studies have shown that theseproducts generally do not work as advertised. Unlike "hand-free"kits, these so-called "shields" may interfere with proper operation ofthe phone. The phone may be forced to boost its power tocompensate, leading to an increase in RF absorption. In February2002, the Federal trade Commission (FTC) charged two companiesthat sold devices that claimed to protect wireless phone users fromradiation with making false and unsubstantiated claims.According to FTC, these defendants lacked a reasonable basis tosubstantiate their claim.What about wireless phone interference withmedical equipment?Radio frequency energy (RF) from wireless phones can interact withsome electronic devices. For this reason, FDA helped develop adetailed test method to measure electromagnetic interference (EMI)of implanted cardiac pacemakers and defibrillators from wirelesstelephones. This test method is now part of a standard sponsored bythe Association for the Advancement of Medical instrumentation
