Palm Treo 650, Руководство пользователя

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306 Section 5A: Safety
Very high levels of electromagnetic energy, such as is found in X-rays and gamma rays can
ionize biological tissues. Ionization is a process where electrons are stripped away from their
normal locations in atoms and molecules. It can permanently damage biological tissues
including DNA, the genetic material. Ionization only occurs with very high levels of
electromagnetic energy such as X-rays and gamma rays. Often the term radiation is used
when discussing ionizing radiation (such as that associated with nuclear power plants).
The energy levels associated with radiofrequency energy, including both radio waves and
microwaves, are not great enough to cause the ionization of atoms and molecules.
Therefore, RF energy is a type of non-ionizing radiation. Other types of non-ionizing
radiation include visible light, infrared radiation (heat) and other forms of electromagnetic
radiation with relatively low frequencies.
Large amounts of RF energy can heat tissue. This can damage tissues and increase body
temperatures. Two areas of the body, the eyes and the testes, are particularly vulnerable to
RF heating because there is relatively little blood flow in them to carry away excess heat.
The amount of RF radiation routinely encountered by the general public is too low to
produce significant heating or increased body temperature. Still, some people have
questions about the possible health effects of low levels of RF energy. It is generally agreed
that further research is needed to determine what effects actually occur and whether they
are dangerous to people. In the meantime, standards-setting organizations and government
agencies are continuing to monitor the latest scientific findings to determine whether
changes in safety limits are needed to protect human health.
FDA, EPA and other US government agencies responsible for public health and safety have
worked together and in connection with WHO to monitor developments and identify
research needs related to RF biological effects.
What levels of RF energy are considered safe?
Various organizations and countries have developed standards for exposure to
radiofrequency energy. These standards recommend safe levels of exposure for both the
general public and for workers. In the United States, the FCC has used safety guidelines for
RF environmental exposure since 1985.