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<br /> Towers 100 feet or more in height shall be located on the lot so watts, the typical cell sire emits 100 watts of power or less,
<br /> that the distance from the base of the tower to any adjoining sometimes as little as 10 in urban areas.
<br /> property line or supporting structure of another tower is a It should be noted that some ordinances,like Multnomah _
<br /> minimum of 100 percent of the proposed cower height.No Counry's, include provisions that automatically apply more
<br /> variance shall be granted from this minimum setback stringent standards if those are ever issued b the federal
<br /> requirement.Towers less than 100 feet in height that cannot Y
<br /> satisfy this 100 percent setback requirement may be approved government. For more information about the relationship of
<br /> by the board,provided that the applicant present a certification cellular communications to EMFs,planners may consult the
<br /> from a registered engineer that the tower will withstand winds Electromagnetic Energy Association, 1255 23rd Sc., NW,
<br /> of 100 miles per hour. Washington, DC 20037; 202-452-1070. EEA is a nonprofit .
<br /> group representing corporations and individuals associated with
<br /> Some communities also determine setbacks by what are industries chat use non-ionizing EMFs.
<br /> considered acceptable levels of electromagnetic radiation.
<br /> Oldham County;Jefferson County,Colorado; Multnomah For More Information
<br /> County, Oregon;and King County,Washington,all have
<br /> specific provisions related to the electromagnetic fields(EMFs) on EMFs • • •
<br /> generated by the new cower.Thc�efferson County ordinance
<br /> requires a complete non-ionizing electromagnetic radiation
<br /> (NIER)analysis with every cower application. o assist local governments in developing
<br /> regulations for siting cellular towers,the American
<br /> Electromagnetic Fields atignal Standards institute has published the
<br /> The health risks associated with EMFs have been the second tandds of the Institute of Electrical and Electronics
<br /> greatest source of community opposition to the siting of cellular Engineers in IEEE Standard for Safety Levels with Respect
<br /> phone towers for reasons related to both personal safety and the to Human Exposure to Radio Frequency Electromagnetic
<br /> —Fields,3KHz to 300 CHz, 1992(ANSUIEEE C.95.1-1992
<br /> perceived impact on property values. EMFs are divided into two (Redeu4nation as ANSUIEEE C95.1-1991().Another
<br /> basic categories. Ionizing radiation includes X-rays and gamma useful ANSI document is Recommended Practice for the
<br /> rays. Non-ionizing radiation,the category to which cellular Measurement of Potentially Hazardous Electromagnetic
<br /> communication devices,radio and TV broadcasting antennas, fields—RF and Microwave(ANSUIEEE C95.3-1992).
<br /> and satellite stations belong,is considered less powerful because Order from American National Standards Institute, 11
<br /> it does not strip the electrons from atoms and molecules to form -- W.42nd St-New York,NY 10036;212-642-4900.Also
<br /> highly reactive panicles known as ions. Instead,it harnesses see the IEEE position statement,"Human Exposure to
<br /> energy gen-crated from the vibration of molecules to convey Radiofrequency Fields for Portable and Mobile Tele-
<br /> information or,in the case of microwave ovens or electric phones and Other Communications Devices,1992."
<br /> blankets,to create heat. Though it predates the advent of cellular communi-
<br /> cations,1979,scientists have conducted more than 1,000 a good source for general information on the
<br /> regulation of radio and television towers is PAS Report
<br /> studies,some of which have linked non-ionizing 11384,Regulating Radio and TV Towers,by Beverly
<br /> electromagnetic field sources to higher incidences of cancer Bookin and Larry Epstein(Chicago:American Planning
<br /> among children living in close proximity to an EMF source. Association, 1984).For more information on EMFs in
<br /> However, these studies,often cited in opposition to the siting of eneral,consult PAS Report M435,£lectroma g netic
<br /> power lines and communication antennas,have also been found Ids and land-Use Controls,by
<br /> inconclusive because they were unable to isolate their findings a Matthe Connelly( hi `
<br /> to a single EMF source.This is because most homes are 8 iggi). !' ,
<br /> equipped with a variety of modern appliances that generate PI ers.
<br /> varying EMF levels. No scientific study has shown a specific o 03.V2
<br /> correlation between cancer and the NIER levels geaerued by a
<br /> cellular communication facility or device.Likewise,no scientific
<br /> research has proven them to be completely safe. >
<br /> The cellular radio system operates in the 800-900 megahertz
<br /> (MHz) ultra-high frequency band,formerly used for UHF Other Standard Provisions
<br /> television broadcasting.Currently there are no general federal Colocatiom In order to minimize tower proliferation,most
<br /> guidelines for what is considered acceptable public exposure to communities require applicants to exhaust all possible avenues
<br /> radio-frequency-emicted radiation.The U.S.Environmental for sharing space on existing towers,usually in a section of the
<br /> Protection Agency is developing such standards,but,in the ordinance on coloration or shared use. Factors that determine
<br /> meantime, many communities are relying on the American feasibility include available space on existing towers,the tower
<br /> National Standards Institute for professionally acceptable radio owner's ability to lease space,the tower's structural capacity,
<br /> frequency emissions standards for all types of communication radio frequency interference,geographic service area
<br /> towers(see box on page 3). Many of the ordinances we reviewed requirements, mechanical or electrical incompatibilities, the
<br /> incorporate the ANSI standards into their review process and comparative costs of coloration and new construction,and any
<br /> approval requirements.Though too detailed to list here, they FCC limitations on rower sharing.
<br /> present acceptable levels of NIER exposures from cowers Many ordinances name the regional or state communications
<br /> operating at various frequencies. division responsible for tracking the availability of suitable
<br /> Of all transmitting facilities,cellular towers typically operate sharing space on towers. Local regulations should be developed
<br /> at the lowest power levels.While a television cower emits up to in tandem with such agencies. In Palm Beach Count Florida
<br /> 5 million watts,and commercial radio stations up to 100,000 tower applicants must send a certified mail announcement co all
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