User Manual

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These studies investigated possible associations between the use of wireless devices and primary brain cancer (glioma,
meningioma, acoustic neuroma, other brain tumors, and salivary gland tumors), leukemia, or other types of cancer. None
of the studies demonstrated the existence of any harmful health effects from wireless device RF exposures. However,
none of the studies can provide absolute findings about long-term exposures since the average period of wireless device
use in these studies was approximately three years.
4. What kinds of devices are the subjects of this update?
Here the term “wireless device” refers to handheld wireless device with built-in antennas, often called “cell”, “mobile”, or
“PCS” wireless devices. These types of wireless devices can expose the user to measurable Radio Frequency (RF)
energy because of the short distance between the wireless device and the user’s head. These RF exposures are limited
by FCC safety guidelines that were developed with the advice of the FDA and other federal health and safety agencies.
When the wireless device is located at greater distances from the user, the exposure to RF is drastically reduced due to
a person's RF exposure rapidly decreasing with increasing distance from the source.
The so-called “cordless devices,” which have a base unit connected to the telephone wiring in a house, typically operate
at far lower power levels, thus producing RF exposures far below the FCC safety limits.
5. What is the FDA doing to find out more about the possible health effects of wireless device RF?
The FDA is working with the U.S. National Toxicology Program and with groups of investigators around the world to
ensure that high-priority animal studies are conducted to address concerns about the effects of exposure to Radio
Frequency (RF) energy.
The FDA has been a leading participant in the World Health Organization International Electro Magnetic Fields (EMF)
Project since its inception in 1996. An influential result of this work has been the development of a detailed agenda of
research needs that has implemented new research programs around the world. The project has also resulted in a
series of public information documents on EMF issues. The FDA and the Cellular Telecommunications & Internet
Association (CTIA) have a formal Cooperative Research and Development Agreement (CRADA) to conduct research on
wireless device safety. The FDA provides the scientific oversight, obtaining input from experts in government, industry,
and academic organizations. CTIA-funded research is conducted through contracts with independent investigators. The
initial research will include both laboratory studies and studies of wireless device users. The CRADA will also include a
broad assessment of additional research needs in the context of the latest research developments around the world.
6. What research is needed to decide whether RF exposure from wireless devices poses a health risk?
A combination of laboratory studies and epidemiological studies of people actually using wireless devices would provide
some of the vital data. Lifetime animal exposure studies could be completed in a few years. However, very large
numbers of animals would be needed to provide reliable proof of a cancer-promoting effect, if one exists.
Epidemiological studies can provide data that is directly applicable to human populations, but ten or more years of
follow-up research may be needed to provide answers about certain health effects, such as cancer.
This is due to the interval between exposure time to a cancer-causing agent and the rate for which tumors develop - if
they do. This could take several years into the future. The interpretation of epidemiological studies is hampered by
difficulties in measuring actual RF exposure during day-to-day use of wireless devices. Many factors affect this
measurement, such as the angle at which the wireless device is held, or which model of wireless device is used.
7. What has the FDA done to measure the Radio Frequency energy coming from wireless devices?
The Institute of Electrical and Electronic Engineers (IEEE) is developing a technical standard for measuring the Radio
Frequency (RF) energy exposure from wireless devices 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 device 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 wireless device. 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 mill-watts/g) of matter. This measurement is used to determine
whether a wireless device complies with safety guidelines.