Palm Treo 650 (Sprint) Guide de l'utilisateur télécharger pdf (Page 324)

312 Section 5A: Safety

shaped, like a piece of pie. As with all forms of electromagnetic energy, the power decreases

rapidly as one moves away from the antenna. Therefore, RF exposure on the ground is much

less than exposure very close to the antenna and in the path of the transmitted radio signal.

In fact, ground-level exposure from such antennas is typically thousands of times less than

the exposure levels recommended as safe by expert organizations. So exposure to nearby

residents would be well within safety margins.

Cellular and PCS base stations in the United States are required to comply with limits for

exposure recommended by expert organizations and endorsed by government agencies

responsible for health and safety. Measurements made near cellular and PCS base station

antennas mounted on towers have confirmed that ground-level exposures are typically

thousands of times less than the exposure limits adopted by the FCC. In fact, in order to be

exposed to levels at or near the FCC limits for cellular or PCS frequencies an individual would

essentially have to remain in the main transmitted radio signal (at the height of the

antenna) and within a few feet from the antenna. This is, of course, very unlikely to occur.

When cellular and PCS antennas are mounted on rooftops, RF levels on that roof or on others

near by would probably be greater than those typically encountered on the ground. However,

exposure levels approaching or exceeding safety guidelines should be encountered only very

close to or directly in front of the antennas. In addition, for sector-type antennas, typically used

for such rooftop base stations, RF levels to the side and in back of these antennas are

insignificant. General guidelines on antenna installations and circumstances that might give

rise to a concern about an facility's conformance with FCC regulations can be found in A Local

Government Official's Guide to Transmitting Antenna RF Emission Safety: Rules, Procedures,

and Practical Guidance. This Guide can be accessed at: http://www.fcc.gov/oet/rfsafety.

Who regulates exposure to radiation from microwave ovens, television sets

and computer monitors?

The Food and Drug Administration is responsible for protecting the public from harmful

radiation emissions from these consumer products.

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Palm Treo 650 (Sprint) Guide de l'utilisateur Page 324