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<br /> Towers 100 feet or more in height shall be located on the lot so warts, the typical cell site emits 100 watts of power or Icss,
<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 cower is a It should be noted chat some ordinances,like Multnomah
<br /> minimum of 100 percent of the proposed tower height.No County's,include provisions that automatically apply more
<br /> variance shad be granted from this minimum setback stringent standards if those are ever issued by the federal
<br /> requirement.Towers lets dean 100 feet in height that cannot government. For more information about the relationship of
<br /> satisfy this 100 percent setback requirement may be approved P
<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 St..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 EIMFs.
<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(E�IIFs)
<br /> on EMFs
<br /> generated by the new tower.TheJefferson County ordinance
<br /> requires a complete non-ionizing electromagnetic radiation
<br /> (NIER) analysis with every cower application. o assist local governments in developing
<br /> reg+tions for siting cellular towers,the American
<br /> glleltfret#O9ftl�{Het; �i�ldi npnal Standards Institute has published the
<br /> The health risks associated with EMFs have been the second �6TUA:o f the institute of Electrical and Electronics
<br /> greatest sours of community opposition to the:icing of cellular Engineers in IEEE Standard for Sakty Levels with Respect
<br /> hone cowers for reasons related co both personal and the ro Human Exposure ro Radio Frequency Electromagnetic
<br /> P Y , _Fields,AKAz to 300 GHz, 1992(ANSOEEE C.95.1-1992
<br /> perceived impact on property values. EMFs are divided into two lRedisi>nation as ANSOEEE C95.1-19911).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(ANSWEE 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!;Now York,NY 10036;212.642-4900.Also
<br /> highly reactive particles 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 /> phones or,in the case of microwave ovens or electric and Other ConymoiWranoes Devices.1992''
<br /> Thoug%it predates the advem
<br /> blanke to create hat. t d cellular communi-
<br /> ts,
<br /> Since 1979,scientists have conducted more dun 1,000 cations,a good source for general information on the
<br /> regulation of radio card televisions 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 dose proximity to an EMF source. Association, 19841.For mac information on EMFs in
<br /> However, these studies,often cited in opposition to the siting of eneral,conwit PAS Report•435,FlecOVnrsare
<br /> power lines and communication antennas,have also been found Land-Um Cabn&&ok by a
<br /> inconclusive because they were unable to isolate their findings a Connally( hi
<br /> to a single EMF source.This is because most hothes are
<br /> equipped with a variety of modem appliances that generate 2
<br /> varying EMF levels.No sciendf a study has shown a specific
<br /> correlation between cancer and the NIER levels genaaied Wyy a
<br /> cellular communication facility or device.Likewim no scientific ' '
<br /> research has proven them to be ccinggeteiy safe. >
<br /> The cellular radio system opaam in the 800-900 megahertz
<br /> (MHz) ultra-high fiegmmq btutd.formerly used for UHF Ol1w std dam MVISIMN
<br /> television broadcasting,(twenty diets are no general federal Colecadea In order to minimize tower proliferation,most
<br /> guidelines for what is---"--A acceptable public exposure w communities require applicants to exhaust all possible avenues
<br /> radio-frequen"mitted radiation-The U.S.Envimemental for sharing space on-existing towers.usually in a section of the
<br /> Protection Agency is developing such sutndards.but,in the ordinance on coloration or shared rise.Factors chat 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 ownw s ability to lase space,the tower's structural capacity,
<br /> frequency emissions standards for all types of communication radio frequency interference,geographic service arm
<br /> towers(see box on page 3).Many of the ordinances we reviewed requirements,mechanical or electrical,incompatibilitie&the
<br /> incorporate the ANSI standards into their review process and comparative costs of coloration and new consauction.and any
<br /> approval requirements.Though too detailed w list here,they FCC limitations on tower sharing.
<br /> present acceptable levels of NIER e:poaures from towers 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 cypiaUy operate sharing space on towers.Local regulations should be developed
<br /> at the lowest power levels.While a television tower emits up to in tandem with such agencies. In Palm W%1XL Florida"
<br /> 5 million warts,and commercial radio stations up to 100,000 tower applicants must send a certified mail announcement to all
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