SAR is the measurement of the amount of energy
absorbed in tissue, either by the whole body or a
small part of the body. It is measured in watts/kg
(or milliwatts/g) of matter. This measurement
is used to determine whether a wireless phone
complies with safety guidelines.
9. What steps can I take to reduce my exposure
to radiofrequency energy from my wireless
phone?
If there is a risk from these products—and at
this point we do not know that there is—it is
probably very small. But if you are concerned
about avoiding even potential risks, you can take
a few simple steps to minimize your exposure to
radiofrequency energy (RF). Since time is a key
factor in how much exposure a person receives,
reducing the amount of time spent using a
wireless phone will reduce RF exposure.
• If you must conduct extended conversations by
wireless phone every day, you could place more
distance between your body and the source
of the RF, since the exposure level drops off
dramatically with distance. For example, you
could use a headset and carry the wireless phone
away from your body or use a wireless phone
connected to a remote
antenna. Again, the
scientific data do not demonstrate that wireless
phones are harmful.
Manufacturers of wireless phones must report
the RF exposure level for each model of phone
to the FCC. The FCC website (http://www.fcc.gov/
oet/rfsafety) gives directions for locating the FCC
identification number on your phone so you can
find your phone’s RF exposure level in the online
listing.
8. What has FDA done to measure the
radiofrequency energy
coming from wireless
phones?
The Institute of Electrical and Electronic Engineers
(IEEE) is developing a technical standard for
measuring the radiofrequency energy (RF)
exposure from wireless phones and other wireless
handsets with the participation and leadership
of FDA scientists and engineers. The standard,
“Recommended Practice for Determining the
Spatial-Peak Specific Absorption Rate (SAR) in the
Human Body Due to Wireless Communications
Devices: Experimental Techniques,” sets forth the
first consistent test methodology for measuring
the rate at which RF is deposited in the heads
of wireless phone users. The test method
uses a tissue-simulating model of the human
head. Standardized SAR test methodology is
expected to greatly improve the consistency of
measurements made at different laboratories on
the same phone.
148 149
SAFETY SAFETY
