User manual

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in laboratory animals. However, many of the studies that showed increased tumor
development used animals that had been genetically engineered or treated with cancer-
causing chemicals so as to be pre-disposed to develop cancer in the absence of RF
exposure. Other studies exposed the animals to RF for up to 22 hours per day. These
conditions are not similar to the conditions under which people use wireless phones, so it
is largely unknown what the results of such studies mean for human health and safety.
Three large epidemiology studies have been published since December 2000. These
studies investigated possible associations between the use of wireless phones 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 phone RF exposures. However, none
of the studies can provide absolute findings about long-term exposures since the average
period of phone use in these studies was approximately three years.
4. What kinds of phones are the subjects of this update?
Here the term “wireless phone” refers to handheld wireless phones with built-in antennas,
often called “cell” or “mobile” phones. These types of wireless phones can expose the user
to measurable Radio Frequency (RF) energy because of the short distance between the
phone 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 phone 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 phones,” 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.