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%4-;7 FCC Radio Frequency Protection Guide The U.S. Congress required (1996 Telecom Act) the Federal Communications Commission ("FCC") to adopt a nationwide human exposure standard to ensure that its licensees do not, cumulatively, have a significant impact on the environment. The FCC adopted the limits from Report No. 86, "Biological Effects and Exposure Criteria for Radiofrequency Electromagnetic Fields," published in 1986 by the Congressionally chartered National Council on Radiation Protection and Measurements, which are nearly identical to the more recent Institute of Electrical and Electronics Engineers Standard C95.1-1999, "Safety Levels with Respect to Human Exposure to Radio Frequency Electromagnetic Fields, 3 kHz to 300 GHz." These limits apply for continuous exposures from all sources and are intended to provide a prudent margin of safety for all persons, regardless of age, gender, size, or health. As shown in the table and chart below, separate limits apply for occupational and public exposure conditions, with the latter limits (in italics and/or dashed) up to five times more restrictive: Frequency Applicable Range (MHz) 0.3 - 1.34 1.34 - 3.0 3.0 - 30 30 - 300 300 - 1,500 1.500 - 100,000 ,-., ... >-. "',... u ."= Ô ~ ;!!--- 0 Qj ~ :... 0 E - 1000 100 10 Electromagnetic Fields (f is ftequency of emission in MHz) Electric Magnetic Equivalent Far-Field Field Strength Field Strength Power Density (VIm) (Nm) (mW/cm2) 614 614 1.63 1.63 100 100 614 823.811 1.63 2.19/1 100 1801/ 1842/f 823.811 4.89/f 2.19/1 900lf 1801/ 61.4 27.5 0.163 0.0729 1.0 0.2 3.54..Jf 1.5* ..Jf1l06 {¡1238 f/300 f/1500 137 61.4 0.364 0.163 5.0 1.0 ./ Occupational Exposure /' PCS Cell I 0.1 ----, 0.1 10 100 103 Frequency (MHz) 105 104 I Higher levels are allowed for short periods of time, such that total exposure levels averaged over six or thirty minutes, for occupational or public settings, respectively, do not exceed the limits, and higher levels also are allowed for exposures to small areas, such that the spatially averaged levels do not exceed the limits. However, neither of these allowances is incorporated in the conservative calculation formulas in the FCC Office of Engineering and Technology Bulletin No. 65 (August 1997) for projecting field levels. Hammett & Edison has built those fonnulas into a proprietary program that calculates, at each location on an arbitrary rectangular grid, the total expected power density from any number of individual radio sources. The program allows for the description of buildings and uneven terrain, if required to obtain more accurate projections. "~;~;;,,;.\ii HAMMEIT & EDISON, INc. <iP , ,;.';;;., CO\:5L'L TI:\'G E]\;GIl'o'EERS ,hc'i ~,S"': SA' FRA\:ClSCO FCC Guidelines Figure 1 .. ""--'-""""'~"-""-'-"'--""-'-'T""""""'--"""