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HomeMy WebLinkAboutAntenna Site FCC RF Compliance Assessment and Report �0M Mam*ig Boarirl PINNACLE TELECOM GROUP t. Professional and Technical Services Telecom Comulliq ANTENNA SITE FCC RF COMPLIANCE ASSESSMENT ANd REPORT PREPAREd FOR NEW YORK SMSA LIMITEd PARTNERShip d/b/A VERIZON WIRELESS "EAST MARION" SITE 9245 MAiN ROAd EAST MARION, NY AuquST 13, 2015 14 RidGEdAIE AVENUE - SUITE 260 • WAR 160115, NJ 07927 • 973.451.1630 I CONTENTS INTROdUCTION ANd SUMMARY 3 ANTENNA ANd TRANSMISSION DATA 5 COMpIIANCE ANAlySiS 7 COMpHANCE CONCLUSION 12 CERTIFICATION 13 AppENdix A. BAckc,ROUNd ON THE FCC MPE LimiT 2 INTRMUCTION ANd SUMMARY At the request of New York SMSA Limited Partnership d/b/a Verizon Wireless ("Verizon Wireless"), Pinnacle Telecom Group has performed an independent assessment of radiofrequency (RF) levels and related FCC compliance for a proposed wireless base station antenna operation inside a "concealment pole" at 9245 Main Road in East marion, NY. Verizon Wireless refers to the site as "East Marion", and its proposed antenna operation involves directional panel antennas and transmission in the 746 MHz, 1900 MHz, and 2100 MHz frequency bands licensed to Verizon Wireless by the FCC. The FCC requires wireless antenna operators to perform an assessment of potential human exposure to radiofrequency (RF) fields emanating from all the transmitting antennas at a site whenever antenna operations are added or modified, and to ensure compliance with the Maximum Permissible Exposure (MPE) limit in the FCC regulations. In this case, the compliance assessment needs to include existing antenna operations at the site by AT&T, T-Mobile, MetroPCS, and the East Marion Fire District. Note that FCC regulations require any future antenna collocators to assess and assure continuing compliance based on the cumulative effects of all then-proposed and then-existing antennas at the site. This report describes a mathematical analysis of RF levels resulting around the site in areas of unrestricted public access, that is, at ground level around the site. The compliance analysis employs a standard FCC formula for calculating the effects of the antennas in a very conservative manner, in order to overstate the RF levels and to ensure "safe-side" conclusions regarding compliance with the FCC limit for safe continuous exposure of the general public. The results of a compliance assessment can be explained in layman's terms by describing the calculated RF levels as simple percentages of the FCC MPE limit. If the reference for that limit is 100 percent, then calculated RF levels higher than 100 percent indicate the MPE limit is exceeded, while calculated RF levels consistently lower than 100 percent serve as a clear and sufficient demonstration 3 of compliance with the MPE limit. We will also describe the overall worst-case calculated result via the "plain-English" equivalent"times-below-the-limit factor". The result of the FCC RF compliance assessment in this case is as follows: ❑ At street level around the site, the conservatively calculated maximum RF level from the combination of proposed and existing antenna operations is 3.3544 percent of the FCC general population MPE limit. In other words, even with the significant degree of conservatism in the calculations, the worst-case calculated RF level is more than 29 times below the FCC limit for safe, continuous human exposure to the RF emissions from antennas. ❑ The results of the analysis demonstrate clear compliance with the FCC general population MPE limit. Moreover, because of the conservative methodology and incorporated assumptions, RF levels actually caused by the antennas will be even less significant than the calculation results here indicate. The remainder of this report provides the following. ❑ relevant technical data on the proposed Verizon Wireless antenna operations, as well as on the existing antenna operations at the site; ❑ descriptions of the applicable FCC mathematical models for assessing MPE compliance, and application of the relevant technical data to those models; and a the results of the analysis, and the compliance conclusion for the site. In addition, Appendix A provides background on the FCC MPE limit, along with a list of FCC references on compliance. 4 ANTENNA ANd TRANSMISSION DATA The table that follows provides the key compliance-related data for the Verizon Wireless antenna operations, as proposed to be modified. General Data Frequency Bands_ 746 MH;z, 1900 MHz and 2100 MHz Service e TGrp Sectonz Coverag ... e..d s__) e -.(3 sector .......... Antenna Type ....... ...... Directional Panel� Antenna Model _... .. Amenol CWWX063X25000_.. ......... „ _„ CenterlineAntenna Antenna Line Loss -Height AGL .. Conservat'vel i nored LL ass i umed 0 dB) 746 MHz Antenna Data Antenna Maximum Gam 16.3 dBi RF Channels�mmSector �� 2 , 40 watts 1900 MHz Antenna Data � .... mer Sector4 16 watts and � tenna Maxi 17.0 dBi _._ _. . ......... RF Channels 4 t 40 watts 2100 MHz Anfenna Data Antenna Maximum Gain,-� -�17.3 dBi RF Channels per Sector _?_a40 watts The antenna vertical-plane radiation pattern is used in the calculations of RF levels at street level around a site. By way of illustration, Figure 1 that follows shows the vertical-plane pattern of the proposed antenna model in the 1900 MHz band. In this type of antenna pattern diagram, the antenna is effectively pointed at the three o'clock position (the horizon) and the pattern at different angles is described using decibel units. Note that the use of a decibel scale to describe the relative pattern at different angles actually serves to significantly understate the actual focusing effects of the antenna. Where the antenna pattern reads 20 dB the relative RF energy emitted at the corresponding downward angle is 1/100th of the maximum that occurs in the main beam (at 0 degrees); at 30 dB, the energy is only 1/1000th of the maximum. Note that the automatic pattern-scaling feature of our internal software may skew side-by-side visual comparisons of different antenna models, or even different parties' depictions of the same antenna model. 5 Figure 1. Amphenol CWWX063X25G00 -1900 MHz Vertical-plane Pattern , 0 deg horizon � f , 'v 5 dB/division As noted at the outset, there are existing antenna operations to include in the compliance assessment. For each of the wireless carriers, we will conservatively assume operation with maximum channel capacity and at maximum transmitter power in each of their respective FCC-licensed frequency bands. For the other operator, we will rely on the transmission parameters in its FCC license. AT&T is licensed to operate in the 700, 850, 1900 and 2350 MHz frequency bands. In the 700 MHz band, AT&T uses as many as four RF channels per antenna sector and a maximum transmitter power of 40 watts. In the 850 MHz band, AT&T uses two 20-watt channels and two 40-watt channels per sector. In the 1900 MHz band, AT&T uses two 60-watt channels and two 80-watt channels per sector. In the 2350 MHz band, AT&T uses two 50-watt channels per sector. T-Mobile is licensed to operate in the 700 MHz, 1900 MHz and 2100 MHz frequency bands. In the 700 MHz band, T-Mobile uses one 40-watt channel per sector. In the 1900 MHz band, T-Mobile uses four 20-watt channels and one 40- watt channel (for a total of 120 watts) per sector. In the 2100 MHz band, 6 T-Mobile uses one 80-watt channel and two 40-watt channels (for a total of 160 watts) per sector. MetroPCS is licensed to transmit in the 2100 MHz frequency band, and uses three 24-watt channels and one 60-watt channel in each antenna sector. In addition, a search of FCC licensing records shows that the East Marion Fire District is authorized for omnidirectional transmission in the 46 MHz band with a maximum transmitter power of 30 watts, and in the 453 MHz band with a maximum transmitter power of 50 watts. COMPLIANCE ANA1y5i5 FCC Office of Engineering and Technology Bulletin 65 ("OET Bulletin 65") provides guidelines for mathematical models to calculate the RF levels at various points around transmitting antennas. At street-level around an antenna site (in what is called the "far field" of the antennas), the RF levels are directly proportional to the total antenna input power and the relative antenna gain in the downward direction of interest — and the levels are otherwise inversely proportional to the square of the straight-line distance to the antenna. Conservative calculations also assume the potential RF exposure is enhanced by reflection of the RF energy from the intervening ground. Our calculations will assume a worst-case 100% "perfect' reflection. The formula for street-level RF compliance calculations for any given wireless antenna operation is as follows: MPE% _ 000 *TxPower* 10(Gmax-Vdisc/10) *4 )/ ( MPE *471* Rz ) where MPE% = RF level, expressed as a percentage of the MPE limit applicable to continuous exposure of the general public 100 = factor to convert the raw result to a percentage 7 TxPower = maximum net power into antenna sector, in milliwatts, a function of the number of channels per sector, the transmitter power per channel, and line loss 10 (Gmax-vdis®/io) = numeric equivalent of the relative antenna gain in the downward direction of interest, referenced to any applied antenna mechanical downtilt; data on the antenna vertical-plane pattern is taken from manufacturer specifications 4 = factor to account for a 100-percent-efficient energy reflection from the ground, and the squared relationship between RF field strength and power density(2z=4) MPE = FCC general population MPE limit R = straight-line distance from the RF source to the point of interest, centimeters The street-level MPE% calculations are performed out to a distance of 500 feet from the facility to points 6.5 feet (approximately two meters, the FCC- recommended standing height) off the ground, as illustrated in the Figure 2, below, antenna height from •"-..M` R antenna- , bottom to M� 6.5' above ground ..`"" ` . level 0 500 Ground Distance D from the site Figure 2. MPE% Calculation Geometry 8 It is popularly understood that the farther away one is from an antenna, the lower the RF level — which is generally but not universally correct. The results of MPE% calculations fairly close to the site will reflect the variations in the vertical- plane antenna pattern as well as the variation in straight-line distance to the antennas. Therefore, RF levels may actually increase slightly with increasing distance within the range of zero to 500 feet from the site. As the distance approaches 500 feet and beyond, though, the antenna pattern factor becomes less significant, the RF levels become primarily distance-controlled, and as a result the RF levels generally decrease with increasing distance, and are well understood to be in compliance. FCC compliance for a collocated antenna site is assessed in the following manner. At each distance point along the ground, an MPE% calculation is made for the RF contribution from each antenna operation, and the sum of the individual MPE% contributions at each point is compared to 100 percent, the normalized reference for compliance with the MPE limit. We refer to the sum of the individual MPE% contributions as "total MPE%", and any calculated total MPE% result exceeding 100 percent is, by definition, higher than the FCC limit and represents non-compliance and a need to mitigate the potential exposure. If all results are consistently below 100 percent, on the other hand, that set of results serves as a clear and sufficient demonstration of compliance with the MPE limit. Note that according to the FCC, when directional antennas such as the panels commonly used in wireless communications are used, the compliance assessments are based on the RF effect of a single (facing) antenna sector or, in cases of non-identical parameters, the worst-case effect of any individual sector. The following conservative methodology and assumptions are incorporated into the MPE% calculations on a general basis: 1. The antennas are assumed to be operating continuously at maximum power, and at maximum channel capacity. 9 2. The power-attenuation effects of shadowing or other obstructions to the line-of-sight path from the antenna to the point of interest are ignored. 3. The calculations intentionally minimize the distance factor (R) by assuming a 6'6" human and performing the calculations from the bottom (rather than the centerline) of the antenna. 4. The potential RF exposure at ground level is assumed to be 100-percent enhanced (increased) via a "perfect" field reflection from the intervening ground. The net result of these assumptions is to significantly overstate the calculated RF exposure levels relative to the levels that will actually occur— and the purpose of this conservatism is to allow very"safe-side"conclusions about compliance. The table on the next page provides the results of the street-level MPE% calculations for each operator, with the overall worst-case result highlighted in bold in the last column. 10 Distance Wireless Wireless Wireless AT&T T-Moble MetroP Ground Verizon Veriz�rn Verizon East Total CS Marion FD MPE% 746 MHz 1900 MHz 2100 MHz MPE% MPE% MPE% MPE%eft) MPE% MPE% MPE% _ ,... .... 0 0 48,..... E 0135 0 t102.i 0.0145^ 00042 0,0241 0 4145 0 0837 -- ___ .. _,.... _ -- 0.5449 0 0.3830 4071 ., 0 ..... 0.61344 0,5126 20 0 0192 0 0307 0 0034 0 0449 0 0208 AA e _ �� _ ° 87 14071 56 80 0.2830 „ ,0 6_246 0 0216 0 2312 �0 1571 .mmm 0 14:x2 0..6629 2.0952 1.Op 0. .11 3 ...�.__ 10768 .,,.. 0 - 7875 60_____ _2754 0 6513 0 0013 0 1679 0 0893 mF 7 1 120 0.0526 0,6631 0.329 1.2799 0 5960 0 0654 0.7284 2 5917 5 5 1 2893 0 1960 0,072 6 9 3.3544 140 0.0510 0 2520 4.3421 1 0453 0.1075 16 - .-- - 0.0324 .. 8098 0.1662 0.1170 -0.,628.8. 2 0228 180 0,0208 _0.0 94 0,0905 0 _._ _ . 896 0.1535 a 0 0590 0.5492 1.1507 200 0.0264 0.03280.0194 0.1 - 149 0.063 098 0.1447 0 0325 0.4892 ...m 0.8548 220 0.0-......_ ... 332 0 0555.. 0.0008 0.1921 01017 11 0805 0,,4368 09006 240 0.0221 260_ 0,0113 0 0107 0.011$ 0.2445 0.1028 0.0906 0.3678 m 0.8503 280 0.0005..._ 0.0143 0 0114 0.4466 0.1549 0.0626 0.3355 1.0566 71 0.2266 0 0629 0.2897 1A490 300 0.0038 0.0620 0.0041 0 523 ..� 0 4 0.2775 0,0419 0,2526 1.1653 5 W...,...,.. _�.. _... ree� . ...p0.0102 0.0566-- _ 2323 1,0222 320 0 0114 0 0447 0 0070 0 38164 0 2029 0 0246 0 10,9 0.8711 360 0 0178 0 0206 0 0058 0.2626 0.1820 00199 0.1838 0.6925 0 0028 0,'1m899.. 0 0939 0,.0179 0.1727,,,---._ 0.5096 . ® . ........ -.......... 380 0 0237 0 0087 400 0.0277 0.0104 0.0011 0.2054 _0.0350 .002,14 01558 0.4569 0 m ._. .4157 440 0 0311 0 01073 0 0038 0.2845 0 0716 0 0334 0.1415 0 460 0 02$6 0.0158 "',0-.6'0--3-5"---0.4277 OIT060 0.030 1290 0 5710 420 0.0252 0.1873 0 0318 0 01 8 0 _ 9 0 1160 0 6901 500 0.0365 0.0174 0.0080.0146 2 0.3942 0.06 4 2 0 1081 __6.6i'1 3 __. _1 X12 0 1404 0 7995 -......._ 0.._ 0.3644 0.2112 0 0 a....,,..... ...... 11 As indicated, even with the significant degree of conservatism built into the calculations, the maximum calculated RF level is 3.3544 percent—well below the 100-percent reference for compliance, particularly given the conservatism incorporated in the calculations. A graph of the overall street-level calculation results, provided below, provides a clearer visual illustration of the relative compliance of the calculated RF levels. The line representing the overall calculation results does not noticeably rise above the graph's baseline, and shows a clear, consistent margin to the FCC compliance limit. COMPLIANCE ASSESSMENT RESULTS Normalized FCC MPE Limit Total MPE% Results 120 LU 100 a 80 _ — . ...... _.... 0 0 40 _...... 0 200 0 100 200 300 400 500 Distance(ft) COMPLIANCE CONCLUSION According to the FCC, the MPE limit has been constructed in such a manner that continuous human exposure to RF emissions up to and including 100 percent of the MPE limit is acceptable and safe. The analysis in this case shows that at street level around the site the maximum calculated RF level from the combination of proposed and existing antenna 12 operations is 3.3544 percent of the FCC general population MPE limit. In other words, the conservatively calculated worst-case RF level is more than 29 times below the limit for safe, continuous human exposure to the RF emissions from antennas. Note that bbecause of the conservative calculation methodology and operational assumptions we applied in the analysis, RF levels actually caused by the antennas will be even less significant than the calculation results here indicate. CERTifiCATION The undersigned certifies as follows 1. I have read and fully understand the FCC regulations concerning RF safety and the control of human exposure to RF fields (47 CFR 1.1301 et seq). 2. To the best of my knowledge, the statements and information disclosed in this report are true, complete and accurate. 3. The analysis of RF compliance provided herein is consistent with the applicable FCC regulations, additional guidelines issued by the FCC, and industry practice. 4. The results of the analysis indicate that the antenna operations at the subject site will be in compliance with the FCC regulations concerning RF exposure. cJC 8/13/15 .. ....... Patricia A ......� 8tanl�cvicit Date Manager— RF Compliance 13 AppEvdix A. BAckgROUNd ON ThE FCC MPE LiMiT FCC Rules and Regulations As directed by the Telecommunications Act of 1996, the FCC has established limits for maximum continuous human exposure to RF fields. The FCC maximum permissible exposure (MPE) limits represent the consensus of federal agencies and independent experts responsible for RF safety matters. Those agencies include the National Council on Radiation Protection and Measurements (NCRP), the Occupational Safety and Health Administration (OSHA), the National Institute for Occupational Safety and Health (NIOSH), the American National Standards Institute (ANSI), the Environmental Protection Agency (EPA), and the Food and Drug Administration (FDA). In formulating its guidelines, the FCC also considered input from the public and technical community—notably the Institute of Electrical and Electronics Engineers (IEEE). The FCC's RF exposure guidelines are incorporated in Section 1.301 et seq of its Rules and Regulations (47 CFR 1.1301-1.1310). Those guidelines specify MPE limits for both occupational and general population exposure. The specified continuous exposure MPE limits are based on known variation of human body susceptibility in different frequency ranges, and a Specific Absorption Rate (SAR) of 4 watts per kilogram, which is universally considered to accurately represent human capacity to dissipate incident RF energy (in the form of heat). The occupational MPE guidelines incorporate a safety factor of 10 or greater with respect to RF levels known to represent a health hazard, and an additional safety factor of five is applied to the MPE limits for general population exposure. Thus, the general population MPE limit has a built-in safety factor of more than 50. The limits were constructed to appropriately protect humans of both sexes and all ages and sizes and under all conditions — and continuous exposure at levels equal to or below the applicable MPE limits is considered to result in no adverse health effects or even health risk. The reason for two tiers of MPE limits is based on an understanding and assumption that members of the general public are unlikely to have had appropriate RF safety training and may not be aware of the exposures they receive; occupational exposure in controlled environments, on the other hand, is assumed to involve individuals who have had such training, are aware of the exposures, and know how to maintain a safe personal work environment. The FCC's RF exposure limits are expressed in two equivalent forms, using alternative units of field strength (expressed in volts per meter, or V/m), and power density (expressed in milliwatts per square centimeter, or mW/cm2). The table on the next page lists the FCC limits for both occupational and general population exposures, using the mW/cm2 reference, for the different radio frequency ranges. 14 Frequency Range(F) Occupational Exposure General Public Exposure (MHz) (mW/cm2) (MW/CM2) 0.3- 1.34 100 100 1.34-3.0 100 180/F2 3.0 -30 900/ F2 180/F2 30-300 1.0 0.2 300 - 1,500 F/300 F/ 1500 1,500- 100,000 5.0 1.0 The diagram below provides a graphical illustration of both the FCC's occupational and general population MPE limits. Power Density (mW/cm2) 100 --- Occupational General Public w ti 'w 5.0 R 5, W by 1.0 Mw v. w fr q e 0.2 __. .._......w........,. „ OI3 1.34 3.0 30 300 1,500 100,000 Frequency(MHz) Because the FCC's MPE limits are frequency-shaped, the exact MPE limits applicable to the instant situation depend on the frequency range used by the systems of interest. 15 The most appropriate method of determining RF compliance is to calculate the RF power density attributable to a particular system and compare that to the MPE limit applicable to the operating frequency in question. The result is usually expressed as a percentage of the MPE limit. For potential exposure from multiple systems, the respective percentages of the MPE limits are added, and the total percentage compared to 100 (percent of the limit). If the result is less than 100, the total exposure is in compliance; if it is more than 100, exposure mitigation measures are necessary to achieve compliance. Note that the FCC "categorically excludes" certain types of antenna facilities from the routine requirement to specifically (i.e., mathematically) demonstrate compliance with the MPE limit. Among those types of facilities are cellular antennas mounted on any type of tower, when the bottoms of the antennas are more than 10 meters (c. 32.8 feet) above ground. The basis for the categorical exclusion, according to the FCC, is the understanding that because of the low power and the directionality of the antennas, such facilities — individually and collectively — are well understood to have no significant effect on the human environment. As a result, the FCC automatically deems such facilities to be in compliance. In addition, FCC Rules and Regulations Section 1.1307(b)(3) describes a provision known in the industry as "the 5% rule". It describes that when a specific location — like a spot on a rooftop — is subject to an overall exposure level exceeding the applicable MPE limit, operators with antennas whose MPE% contributions at the point of interest are less than 5% are exempted from the obligation otherwise shared by all operators to bring the site into compliance, and those antennas are automatically deemed by the FCC to satisfy the rooftop compliance requirement. FCC References on Compliance 47 CFR, FCC Rules and Regulations, Part 1 (Practice and Procedure), Section 1.1310 (Radiofrequency radiation exposure limits). FCC Second Memorandum Opinion and Order and Notice of Proposed Rulemaking (FCC 97-303), In the Matter of Procedures for Reviewing Requests for Relief From State and Local Regulations Pursuant to Section 332(c)(7)(8)(v) of the Communications Act of 1934 (WT Docket 97-192), Guidelines for Evaluating the Environmental Effects of Radiofrequency Radiation (ET Dockel 93-62), and Petition for Rulemaking of the Cellular Telecommunications Industry Association Conceming Amendment of the Commission's Rules to Preempt State and Local Regulation of Commercial Mobile Radio Service Transmitting Facilities, released August 25, 1997. FCC First Memorandum Opinion and Order, ET Docket 93-62, In the Matter of Guidelines for Evaluating the Environmental Effects of Radiofrequency Radiation, released December 24, 1996. 16 FCC Report and Order, ET Docket 93-62, In the Matter of Guidelines for Evaluating the Environmental Effects of Radiofrequency Radiation, released August 1, 1996. FCC Office of Engineering and Technology (OET) Bulletin 65, "Evaluating Compliance with FCC Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields", Edition 97-01,August 1997. 17