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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
“hand-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. In February 2002, the Federal trade
Commission (FTC) charged two companies that
sold devices that claimed to protect wireless
phone users from radiation with making false
and unsubstantiated claims. According to FTC,
these defendants lacked a reasonable basis to
substantiate their claim.
What about wireless phone interference
with medical equipment?
Radio frequency energy (RF) from wireless
phones can interact with some electronic
devices. For this reason, FDA helped develop a
detailed test method to measure
electromagnetic interference (EMI) of implanted
cardiac pacemakers and defibrillators from
wireless telephones. This test method is now
part of a standard sponsored by the Association
for the Advancement of Medical instrumentation
(AAMI). The final draft, a joint effort by FDA,
medical device manufacturers, and many other
groups, was completed in late 2000. This
standard will allow manufacturers to ensure
that cardiac pacemakers and defibrillators are
safe from wireless phone EMI. FDA has tested
wireless phones and helped develop a voluntary
standard sponsored by the Institute of Electrical
and Electronic Engineers (IEEE). This standard
specifies test methods and performance
requirements for hearing aids and wireless
phones so that no interference occurs when a
person uses a compatible phone and a
compatible hearing aid at the same time. This
standard was approved by the IEEE in 2000.
