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at different laboratories on the same phone. 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 prob-
ably 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.
•Ifyoumustconductextendedconversationsbywirelessphoneeveryday,youcouldplacemore
distance between your body and the source of the RF, since the exposure level drops off dramati-
cally 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 scientic data do not demonstrate that
wireless phones are harmful. But if you are concerned about the RF exposure from these products,
you can use measures like those described above to reduce your RF exposure from wireless
phone use.
10. What about children using wireless phones?
The scientic evidence does not show a danger to users of wireless phones, including children
and teenagers. If you want to take steps to lower exposure to radiofrequency energy (RF), the
measures described above would apply to children and teenagers using wireless phones. Reducing
the time of wireless phone use and increasing the distance between the user and the RF source
will reduce RF exposure. Some groups sponsored by other national governments have advised
that children be discouraged from using wireless phones at all. For example, the government in the
United Kingdom distributed leaets containing such a recommendation in December 2000. They
noted that no evidence exists that using a wireless phone causes brain tumors or other ill effects.
Their recommendation to limit wireless phone use by children was strictly precautionary; it was
not based on scientic evidence that any health hazard exists.
11. What about wireless phone interference with medical equipment?
Radiofrequency energy (RF) from wireless phones can interact with some electronic devices. For
this reason, FDA helped develop a detailed test method to measure electromagnetic interfer-
ence (EMI) of implanted cardiac pacemakers and debrillators from wireless telephones. This test
method is now part of a standard sponsored by the Association for the Advancement of Medical
instrumentation (AAMI). The nal 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 debrillators are safe from wireless phone EMI. FDA has tested hear-
ing aids for interference from handheld wireless phones and helped develop a voluntary standard
sponsored by the Institute of Electrical and Electronic Engineers (IEEE). This standard species
test methods and performance requirements for hearing aids and wireless phones so that 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. FDA continues to monitor the use
of wireless phones for possible interactions with other medical devices. Should harmful interfer-
ence be found to occur, FDA will conduct testing to assess the interference and work to resolve
the problem.
12. Where can I nd additional information?
For additional information, please refer to the following resources:
•FDAwebpageonwirelessphones
(http://www.fda.gov/Radiation-EmittingProducts/RadiationEmittingProductsandProcedures/
HomeBusinessandEntertainment/CellPhones/default.htm)
•FederalCommunicationsCommission(FCC)RFSafetyProgram(http://www.fcc.gov/oet/rfsafety)
•InternationalCommissiononNon-IonizingRadiationProtection(http://www.icnirp.de)
•WorldHealthOrganization(WHO)InternationalEMFProject(http://www.who.int/peh-emf/en/)
•NationalRadiologicalProtectionBoard(UK)(http://www.hpa.org.uk/radiation/)
AVOID POTENTIAL HEARING LOSS
Prolonged exposure to loud sounds (including music) is the most common cause of preventable
hearing loss. Some scientic research suggests that using portable audio devices, such as portable
music players and cellular telephones, at high volume settings for long durations may lead to
permanent noise-induced hearing loss. This includes the use of headphones (including headsets,
earbuds and Bluetooth® or other wireless devices). Exposure to very loud sound has also been as-
sociated in some studies with tinnitus (a ringing in the ear), hypersensitivity to sound and distorted
hearing. Individual susceptibility to noise-induced hearing loss and other potential hearing problems
varies.
The amount of sound produced by a portable audio device varies depending on the nature of the
sound, the device, the device settings and the headphones. You should follow some commonsense
recommendations when using any portable audio device:
•Setthevolumeinaquietenvironmentandselectthelowestvolumeatwhichyoucanhear
adequately.
•Whenusingheadphones,turnthevolumedownifyoucannothearthepeoplespeakingnearyou
or if the person sitting next to you can hear what you are listening to.
•Donotturnthevolumeuptoblockoutnoisysurroundings.Ifyouchoosetolistentoyour
portable device in a noisy environment, use noise-cancelling headphones to block out background
environmental noise.
•Limittheamountoftimeyoulisten.Asthevolumeincreases,lesstimeisrequiredbeforeyour
hearing could be affected.
•Avoidusingheadphonesafterexposuretoextremelyloudnoises,suchasconcerts,thatmight
cause temporary hearing loss. Temporary hearing loss might cause unsafe volumes to sound
normal.
•Donotlistenatanyvolumethatcausesyoudiscomfort.Ifyouexperienceringinginyourears,
hear mufed speech or experience any temporary hearing difculty after listening to your portable
audio device, discontinue use and consult your doctor.
YOU CAN OBTAIN ADDITIONAL INFORMATION ON THIS SUBJECT FROM THE
FOLLOWING SOURCES:
AMERICA ACADEMY OF AUDIOLOGY
11730 Plaza American Drive, Suite 300, Reston, VA 20190
Voice: 800-AAA-2336 | Email: infoaud@audiology.org Internet: http://www.audiology.org
