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Activation Report CRAN_RSFR_CUPE0_006 03312022Activation Report • AT&T Mobility • Node No. CRAN_RSFR_CUPE0_006 10185 North Stelling Road • Cupertino, California D4CN Page 1 of 3 ©2022 Statement of Hammett & Edison, Inc., Consulting Engineers The firm of Hammett & Edison, Inc., Consulting Engineers, has been retained on behalf of AT&T Mobility, a personal wireless telecommunications carrier, to evaluate the node located at 10185 North Stelling Road in Cupertino, California, compliance with appropriate guidelines limiting human exposure to radio frequency (“RF”) electromagnetic fields. Executive Summary AT&T had installed a cylindrical antenna above the light pole sited in the public right-of-way near 10185 North Stelling Road in Cupertino. All exposure levels under the existing conditions for anyone in publicly accessible areas nearby were well below the federal standard. Prevailing Exposure Standard 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 limit for exposures of unlimited duration at several wireless service bands are as follows: Transmit “Uncontrolled” Occupational Limit Wireless Service Band Frequency Public Limit (5 times Public) Microwave (point-to-point) 1–80 GHz 1.0 mW/cm2 5.0 mW/cm2 Millimeter-wave 24–47 1.0 5.0 Part 15 (WiFi & other unlicensed) 2–6 1.0 5.0 C-Band 3,700 MHz 1.0 5.0 CBRS (Citizens Broadband Radio) 3,550 1.0 5.0 BRS (Broadband Radio) 2,490 1.0 5.0 WCS (Wireless Communication) 2,305 1.0 5.0 AWS (Advanced Wireless) 2,110 1.0 5.0 PCS (Personal Communication) 1,930 1.0 5.0 Cellular 869 0.58 2.9 SMR (Specialized Mobile Radio) 854 0.57 2.85 700 MHz 716 0.48 2.4 600 MHz 617 0.41 2.05 [most restrictive frequency range] 30–300 0.20 1.0 General Facility Requirements Wireless nodes typically consist of two distinct parts: the electronic transceivers (also called “radios”) that are connected to a central “hub” (which in turn are connected to the traditional wired telephone lines), and the passive antenna(s) that send the wireless signals created by the radios out to be received Activation Report • AT&T Mobility • Node No. CRAN_RSFR_CUPE0_006 10185 North Stelling Road • Cupertino, California D4CN Page 2 of 3 ©2022 by individual subscriber units. The radios are often located on the same pole as the antennas and are connected to the antennas by coaxial cables. 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. Site Description The site was visited by Mr. Scott Walthard, a qualified field technician employed by Hammett & Edison, Inc., during normal business hours on February 25, 2022, a non-holiday weekday. AT&T had installed a small cylindrical antenna about three stories above ground on top of the municipal light pole located in the public right-of-way on the west side of North Stelling Road in Cupertino, near the southwest corner of the intersection between Christensen Drive and North Stelling Road, about 150 feet north of the driveway to the Cupertino Community Center, located at 10185 North Stelling Road. There was observed no other wireless telecommunications base stations located at or next to the site. Notices of testing were delivered by registered U.S. Mail to the three residences within 100 feet of the site, and measurements will be taken on April 7, 2022, within each residence if requested by the occupant. It is expected that exposure conditions in the residences will be well below the applicable limit. Measurement Results The measurement equipment used was a Narda Type NBM-520 Broadband Field Meter with Type EA-5091 Isotropic Electric Field Probe (Serial No. 01035) and a Wandel & Goltermann Type EMR-300 Radiation Meter with Type 8 Isotropic Electric Field Probe (Serial No. P-0036). The meters and probes were under current calibration by the manufacturers. Measurements were made at ground near the site and from a bucket-truck in front of the antenna. At each test point, the measurement results were compared with applicable FCC standards. The maximum power density level observed beyond 2 feet from the antenna was less than the applicable public limit. The maximum power density level observed for a person at ground near the site was 0.00088 mW/cm2, which is 0.44% of the most restrictive public limit. The three-dimensional perimeter of RF power density levels equal to the FCC standard for uncontrolled areas did not extend into any uncontrolled areas. Activation Report • AT&T Mobility • Node No. CRAN_RSFR_CUPE0_006 10185 North Stelling Road • Cupertino, California D4CN Page 3 of 3 ©2022 No Recommended Mitigation Measures Access to the antenna was restricted by its mounting location and height. Since exposure levels in publicly accessible areas were found to be below the applicable public limit, no other access controls or signs are required to meet FCC public guidelines. The operation can be considered intrinsically compliant with the FCC occupational guidelines. Explanatory signs were posted on the pole below the antenna. Conclusion Based upon the information and analysis above, it is the undersigned’s professional opinion that this AT&T M obility node, as installed and operating at the time of the measurements, complies with the FCC standards for limiting public exposure in uncontrolled areas to radio frequency energy and, therefore, does not for this reason cause a significant impact on the environment. 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, 2023. 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. William F. Hammett, P.E. 707/996-5200 March 31, 2022 FCC Radio Frequency Protection Guide FCC Guidelines Figure 1 1000 100 10 1 0.1 0.1 1 10 100 103 104 105 Occupational Exposure Public Exposure PCS CellFM Po w e r De n s i t y (m W / c m 2) 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 ANSI/IEEE 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 Electromagnetic Fields (f is frequency of emission in MHz) Applicable Range (MHz) Electric Field Strength (V/m) Magnetic Field Strength (A/m) Equivalent Far-Field Power Density (mW/cm2) 0.3 – 1.34 614 614 1.63 1.63 100 100 1.34 – 3.0 614 823.8/ f 1.63 2.19/ f 100 180/ f2 3.0 – 30 1842/ f 823.8/ f 4.89/ f 2.19/ f 900/ f2 180/ f2 30 – 300 61.4 27.5 0.163 0.0729 1.0 0.2 300 – 1,500 3.54 f 1.59 f f /106 f /238 f/300 f/1500 1,500 – 100,000 137 61.4 0.364 0.163 5.0 1.0 Frequency (MHz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©