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Apple Park RF Exposure Study.pdfAPPLE INC. AT&T Site No. CCL04017 1 Apple Parkway Sprint Site No. SF96xc030 Cupertino, California T -Mobile Site No. SF14980A Proposed Base Stations Verizon Site No. 278981 Statement of Hammett & Edison, Inc., Consulting Engineers The firm of Hammett & Edison, Inc., Consulting Engineers, has been retained on behalf of Apple Inc., to evaluate the base stations for personal wireless telecommunications carriers AT&T Mobility, Sprint, T -Mobile, and Verizon Wireless (Site Nos. CCL04017, SF96xc030, SF 14980A, and 278981 "Apple Park," respectively) proposed to be located on the Apple Park Main Building (ACO2) at 1 Apple Parkway in Cupertino, California, for compliance with appropriate guidelines limiting human exposure to radio frequency ("RF") electromagnetic fields. Executive Summary Four wireless carriers propose to install directional panel antennas behind the exterior wall of the penthouse above the roof of the four-story Apple Park Main Building located at 1 Apple Parkway in Cupertino. The proposed operations will comply with the FCC guidelines limiting public exposure to RF energy; certain mitigation measures are recommended to comply with FCC occupational guidelines. Prevailing Exposure Standards The U.S. Congress requires that the Federal Communications Commission ("FCC") evaluate its actions for possible significant impact on the environment. A summary of the FCC's exposure limits is shown in Figure 1. These limits apply for continuous exposures and are intended to provide a prudent margin of safety for all persons, regardless of age, gender, size, or health. The most restrictive FCC limit for exposures of unlimited duration to radio frequency energy for several personal wireless services are as follows: Wireless Service Frequency Band Occupational Limit Public Limit Microwave (Point -to -Point) 5-80 GHz 5.00 mW/cm2 1.00 mW/cm2 WiFi (and unlicensed uses) 2-6 5.00 1.00 BRS (Broadband Radio) 2,600 MHz 5.00 1.00 WCS (Wireless Communication) 2,300 5.00 1.00 AWS (Advanced Wireless) 2,100 5.00 1.00 PCS (Personal Communication) 1,950 5.00 1.00 Cellular 870 2.90 0.58 SMR (Specialized Mobile Radio) 855 2.85 0.57 700 MHz 700 2.40 0.48 [most restrictive frequency range] 30-300 1.00 0.20 HAMMETT & EDISON, INC. CONSULTING ENGINEERS C8RQ SAN FRANCISCO Page I of 5 APPLE INC. AT&T Site No. CCL04017 1 Apple Parkway Sprint Site No. SF96xc030 Cupertino, California T -Mobile Site No. SF14980A Proposed Base Stations Verizon Site No. 278981 General Facility Requirements Base stations typically consist of two distinct parts: the electronic transceivers (also called "radios" or "channels") that are connected to the traditional wired telephone lines, and the passive antennas that send the wireless signals created by the radios out to be received by individual subscriber units. The transceivers are often located at ground level and are connected to the antennas by coaxial cables. A small antenna for reception of GPS signals is also required, mounted with a clear view of the sky. Because of the short wavelength of the frequencies assigned by the FCC for wireless services, the antennas require line -of -sight paths for their signals to propagate well and so are installed at some height above ground. The antennas are designed to concentrate their energy toward the horizon, with very little energy wasted toward the sky or the ground. This means that it is generally not possible for exposure conditions to approach the maximum permissible exposure limits without being physically very near the antennas. Computer Modeling Method The FCC provides direction for determining compliance in its Office of Engineering and Technology Bulletin No. 65, "Evaluating Compliance with FCC -Specified Guidelines for Human Exposure to Radio Frequency Radiation," dated August 1997. Figure 2 describes the calculation methodologies, reflecting the facts that a directional antenna's radiation pattern is not fully formed at locations very close by (the "near -field" effect) and that at greater distances the power level from an energy source decreases with the square of the distance from it (the "inverse square law"). The conservative nature of this method for evaluating exposure conditions has been verified by numerous field tests. Site and Facility Description Based upon information provided by Apple, including architectural drawings by Foster + Partners, dated July 10, 2011, four wireless telecommunications carriers — AT&T Mobility, Sprint, T -Mobile, and Verizon Wireless — propose to install base station antennas behind the outside wall of the equipment penthouse atop the four-story, circular office building located at 1 Apple Parkway in Cupertino. The antennas would be mounted at an effective height of about 69 feet above ground, 9 feet above the walkway against that wall, and would be arranged in four groupings around the building, oriented roughly north, east, south, and west. It is noted that the Sprint and T -Mobile antennas are mounted close together in each grouping, except to the south, where T -Mobile does not propose to install antennas. The following information has been provided by the individual carriers: HAMMETT & EDISON, INC. CONSULTING ENGINEERS C8RQ SAN FRANCISCO Page 2 of 5 APPLE INC. 1 Apple Parkway Cupertino, California Proposed Base Stations AT&T AT&T Site No. CCL04017 Sprint Site No. SF96=030 T -Mobile Site No. SF14980A Verizon Site No. 278981 • Zoning drawings by J5 Infrastructure Partners, dated November 7, 2017 • Sixteen CCI Model HPA-65F-BUU-H2 antennas, employing up to 4° downtilt • Oriented in groups of four toward 20°T, 110°T, 200°T and 290°T • Maximum effective radiated power 6,210 watts: 1,340 watts at WCS, 1,960 watts at AWS, 1,640 watts at PCS, 500 watts at cellular, 770 watts at 700 MHz Sprint • Zoning drawings by Fullerton Engineering Design, dated July 18, 2017 • Four Filtronic Model P6T2131701 antennas, employing up to 8° downtilt • Oriented toward 80°T, 170°T, 260°T, and 350°T • Maximum effective radiated power 3,250 watts: 1,280 watts at BRS, 1,610 watts at PCS, 360 watts at SMR T -Mobile • Zoning drawings by Black & Veatch, dated November 6, 2017 • Six CCI Model HPA-6517-13UU-1-12 antennas, employing up to 3° downtilt • Oriented in pairs toward 80°T, 260°T, and 350°T (no antennas oriented toward 170°T) • Maximum effective radiated power 3,600 watts: 1,960 watts at AWS and 1,640 watts at PCS Verizon • Zoning drawings by Streamline Engineering and Design, Inc., dated July 27, 2017 • Sixteen JMA Model X7CQAP-FRO-260 antennas, employing up to 6° downtiIt • Oriented in groups of four toward 30°T, 120°T, 210°T, and 300°T • Maximum effective radiated power 10,860 watts: 5,400 watts at AWS, 2,480 watts at PCS, 1,880 watts at cellular, 1,100 watts at 700 MHz HAMMETT & EDISON, INC. CONSULTING ENGINEERS C8RQ SAN FRANCISCO Page 3 of 5 APPLE INC. 1 Apple Parkway Cupertino, California Proposed Base Stations Study Results AT&T Site No. CCL04017 Sprint Site No. SF96xc030 T -Mobile Site No. SF14980A Verizon Site No. 278981 For a person anywhere at ground, the maximum RF exposure level due to the cumulative operation of all four carriers, including RF emissions from similar antennas on Apple Building TA09 about 1,500 feet to the south, is calculated to be 0.038 mW/cm2, which is 6.0% of the applicable public exposure limit. The maximum calculated level for a person on the top floor of the building is 0.90% of the public exposure limit. The maximum calculated level at the underground garage is less than 0.1% of the public exposure limit. The maximum calculated level at the top -floor elevation of any nearby residence is 5.9% of the public exposure limit; this occurs at the Hamptons Apartment Homes located about 270 feet to the southwest. It should be noted that these results include several "worst- case" assumptions and therefore are expected to overstate actual power density levels from the proposed operation. Exposure levels on the roof of the building may exceed the applicable public limit in certain areas, as shown in Figures 3 and 4. Recommended Mitigation Measures Due to their mounting locations and height, requiring passage through a locked door to reach the roof, the carriers' antennas would not be accessible to unauthorized persons, and so no mitigation measures are necessary to comply with the FCC public exposure guidelines. To prevent occupational exposures in excess of the FCC guidelines, it is recommended that appropriate RF safety training, to include review of personal monitor use and lockout/tagout procedures, be provided to all authorized personnel who have access to the roof, including employees and contractors of the respective carriers and of Apple. No access directly in front of the antennas themselves, such as might occur during certain maintenance activities on the solar panels and at the view screens in front of the antennas, should be allowed while the pertinent antennas are in operation, unless other measures can be demonstrated to ensure that occupational protection requirements are met. As shown in Figure 4, it is recommended that a yellow stripe be painted (centered in front of the antennas for each carrier, except T -Mobile) at the top edge outer wall of the roof walkway, and it is recommended that explanatory signs* be posted at the roof access ladders, at the solar panel access ladders, at the approximate mid -point of each yellow stripe, near the solar panels above the end parts of each yellow stripe, and on the penthouse wall in front of the antennas, readily visible from any angle of approach to persons who might need to work in those areas. * Signs should comply with OET-65 color, symbol, and content recommendations. Contact information for the respective carrier should be provided (e.g., a telephone number) to arrange for access to restricted areas. The selection of language(s) is not an engineering matter, and guidance from the landlord, local zoning or health authority, or appropriate professionals may be required. HaimHAMMETT & EDISON, INC. CONSULTING ENGINEERS C8RQ SAN FRANCISCO Page 4 of 5 APPLE INC. AT&T Site No. CCL04017 1 Apple Parkway Sprint Site No. SF96xc030 Cupertino, California T -Mobile Site No. SF14980A Proposed Base Stations Verizon Site No. 278981 Conclusion Based on the information and analysis above, it is the undersigned's professional opinion that operation of the proposed base stations at 1 Apple Parkway in Cupertino, California, will comply with the prevailing standards for limiting public exposure to radio frequency energy and, therefore, will not for this reason cause a significant impact on the environment. The highest calculated level in publicly accessible areas is much less than the prevailing standards allow for exposures of unlimited duration. This finding is consistent with measurements of actual exposure conditions taken at other operating base stations. Training authorized personnel, marking sections of the outer wall of the roof walkway, and posting explanatory signs are recommended to establish compliance with occupational exposure limits. Authorship The undersigned author of this statement is a qualified Professional Engineer, holding California Registration Nos. E-13026 and M-20676, which expire on June 30, 2019. This work has been carried out under his direction, and all statements are true and correct of his own knowledge except, where noted, when data has been supplied by others, which data he believes to be correct. rE-13-?,h4)"026 M-20676 cl Exp. 6-30-2019 March 21, 2018 HAMMETT & EDISON, INC. CONSULTING ENGINEERS SAN FRANCISCO William F. Hami4tt, P.E. 707/996-5200 C8RQ Page 5 of 5 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 ("NCRP"). Separate limits apply for occupational and public exposure conditions, with the latter limits generally five times more restrictive. The more recent standard, developed by the Institute of Electrical and Electronics Engineers and approved as American National Standard ANSUIEEE C95.1-2006, "Safety Levels with Respect to Human Exposure to Radio Frequency Electromagnetic Fields, 3 kHz to 300 GHz," includes similar limits. 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 1000 100 10 `. 0.1 ElectromaLynetic Fields (f is freauencv of emission in MHz Electric Magnetic Equivalent Far -Field Field Strength Field Strength Power Density MITI) (A/m) (mW/cm2) 614 614 1.63 1.63 100 100 614 823.8/f 1.63 2.19/f 100 180/f 1842/ f 823.8/f 4.89/ f 2.19/f 900/ f' 1801f 61.4 27.5 0.163 0.0729 1.0 0.2 3.54* 1.59ff 4f/106 NFf1238 f/300 f/1500 137 61.4 0.364 0.163 5.0 1.0 Occupational Exposure PCS FM Public 0.1 1 10 100 103 104 105 Frequency (MHz) 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 formulas 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. HAMMETT & EDISON, INC. FCC Guidelines CONSULTING ENGINEERS SAN FRANCISCO Figure 1 RFR.CALCTM Calculation Methodology Assessment by Calculation of Compliance with FCC Exposure Guidelines 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 maximum permissible exposure limits adopted by the FCC (see Figure 1) 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. 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. Near Field. Prediction methods have been developed for the near field zone of panel (directional) and whip (omnidirectional) antennas, typical at wireless telecommunications base stations, as well as dish (aperture) antennas, typically used for microwave links. The antenna patterns are not fully formed in the near field at these antennas, and the FCC Office of Engineering and Technology Bulletin No. 65 (August 1997) gives suitable formulas for calculating power density within such zones. For a panel or whip antenna, power density S = 0 x Ox D Px h ' in mW/Cm2, 9 sw and for an aperture antenna, maximum power density Smax = 0.1x16xi1xP.,, itxh2 where OBW = half -power beamwidth of the antenna, in degrees, and Pnet = net power input to the antenna, in watts, D = distance from antenna, in meters, h = aperture height of the antenna, in meters, and i? = aperture efficiency (unitless, typically 0.5-0.8). The factor of 0.1 in the numerators converts to the desired units of power density. , in mW/cm2, Far Field. OET-65 gives this formula for calculating power density in the far field of an individual RF source: power density S = 2.56 x 1.64 x 100 x RFF2 x ERP 4 x ;r x D2 in mW/cm2, where ERP = total ERP (all polarizations), in kilowatts, RFF = relative field factor at the direction to the actual point of calculation, and D = distance from the center of radiation to the point of calculation, in meters. The factor of 2.56 accounts for the increase in power density due to ground reflection, assuming a reflection coefficient of 1.6 (1.6 x 1.6 = 2.56). The factor of 1.64 is the gain of a half -wave dipole relative to an isotropic radiator. The factor of 100 in the numerator converts to the desired units of power density. This formula has been built into a proprietary program that calculates, at each location on an arbitrary rectangular grid, the total expected power density from any number of individual radiation sources. The program also allows for the description of uneven terrain in the vicinity, to obtain more accurate projections. HEHAMMETT & EDISON, INC. CONSULTING ENGINEERS Methodology SAN FRANCISCO Figure 2 APPLE INC. AT&T Site No. CCL04017 1 Apple Parkway Sprint Site No. SF96xc030 Cupertino, California T -Mobile Site No. SF14980A Proposed Base Stations Verizon Site No. 278981 Calculated RF Exposure Levels on Roof (Antenna Arrangement Typical of Four) Recommended Mitigation Measures • Paint yellow caution stripes (see Figure 4) • Post explanatory signs (see Figure 4) • Provide training Legend. Less Than Exceeds Exceeds Exceeds l Ox Public Public Occupational Occupational Shaded color blank 0 Sign type I - Green $- Blue 'y- Yellow ® - Orange INFORMATION NOTICE CAUTION WARNING HAMMETT & EDISON, INC. CONSULTING ENGINEERS _... SAN FRANCISCO Notes: See text. Base drawing from Black & Veatch, dated November 6, 2017. Calculations performed according to OET Bulletin 65, August 1997. C8RQ Figure 3 APPLE INC. AT&T Site No. CCL04017 1 Apple Parkway Sprint Site No. SF96xc030 Cupertino, California T -Mobile Site No. SF14980A Proposed Base Stations Verizon Site No. 278981 Calculated RF Exposure Levels on Walkway and Solar Panels (Typical for Each Carrier) Legend: Shaded color Boundary marking Sign type Verizon AT&T TP Less Than Exceeds Public Public blank ■ N/A ® - Orange 1- Green $- Blue INFORMATION NOTICE HAMMETT & EDISON, INC. CONSULTING ENGINEERS _.... SAN FRANCISCO Sprint Exceeds Exceeds IOx Occupational Occupational ■ 'Y- Yellow ® - Orange CAUTION WARNING FEET 10 0 10 20 C8RQ Figure 4