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HomeMy WebLinkAboutItem No. 3 - Reso 1970_Part 2 of 2 Attachment No. 7 Documents From Verizon in Support Of the Application Attachment No. 7 JERROLD T. BUSHBERG Ph.D., DABMP, DABSNM, FAAPM, FHPS HEALTH AND MEDICAL PHYSICS CONSULTING 7784 Oak Bay Circle Sacramento, CA 95831 (800) 760-8414–jbushberg@hampc.com Emanuel Higgins July 25, 2016 Project Manager TECTONIC 2081 Business Center Drive, Suite 219 Irvine, CA 92612 Introduction At your request, I have reviewed the technical specifications and calculated the maximum radiofrequency, (RF), power density from the proposed Verizon Wireless facility to be located at 1881 South 1st Street Arcadia, CA, 91006. This facility will be used for wireless telecommunications transmission and reception utilizing 12 CommScope panel antenna model # SBNHH-1D65C, mounted to a bell-tower. The antennae used are directional and designed to transmit with a maximum input power of up to 103.1 watts, with a gain of up to 13.7 dBd at approximately 746 MHz; 173.4 watts, with a gain of up to 15.7 dBd at approximately 1900 MHz; and 157.8 watts with a gain of up to 16.1 dBd at approximately 2,100 MHz. The distance from the antenna center to the ground for all nodes will be at least 45.0 feet. The site configurations is shown in attachment one. The antenna specification details are depicted in attachment two. This analysis represent the worst case potential public exposure utilizing these transmission and antennae specifications. Calculation Methodology Calculations at the level of the antenna were made in accordance with the cylindrical model recommendations for near-field analysis contained in the Federal Communications Commission, Office of Engineering and Technology Bulletin 65 (OET 65) entitled "Evaluating Compliance with FCC-Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields.” RF exposure calculations at ground level were made using equation 10 from the same OET document. Several assumptions were made in order to provide the most conservative or "worse case" projections of power densities. Calculations were made assuming that all channels were operating simultaneously at their maximum design effective radiated power. Attenuation (weakening) of the signal that would result from surrounding foliage or buildings was ignored. Buildings or other structures can reduce the signal strength by a factor of 10 (i.e., 10 dB) or more depending upon the construction material. In addition, for ground level calculations, the ground or other surfaces were considered to be perfect reflectors (which they are not) and the RF energy was assumed to overlap and interact constructively at all locations (which they would not) thereby resulting in the calculation of the maximum potential exposure. In fact, the accumulations of all these very conservative assumptions, will significantly overestimate the actual exposures that would typically be expected from such a facility. However, this method is a prudent approach that errs on the side of safety. 1 RF Safety Standards The two most widely recognized standards for protection against RF field exposure are those published by the American National Standards Institute (ANSI) C95.1 and the National Council on Radiation Protection and measurement (NCRP) report #86. The NCRP is a private, congressionally chartered institution with the charge to provide expert analysis of a variety of issues (especially health and safety recommendations) on radiations of all forms. The scientific analyses of the NCRP are held in high esteem in the scientific and regulatory community both nationally and internationally. In fact, the vast majority of the radiological health regulations currently in existence can trace their origin, in some way, to the recommendations of the NCRP. All RF exposure standards are frequency-specific, in recognition of the differential absorption of RF energy as a function of frequency. The most restrictive exposure levels in the standards are associated with those frequencies that are most readily absorbed in humans. Maximum absorption occurs at approximately 80 MHz in adults. The NCRP maximum allowable continuous occupational exposure at this frequency is 1,000 ìW/cm2. This compares to 5,000 ìW/cm2 at the most restrictive of the PCS frequencies (~1,800 MHz) that are absorbed much less efficiently than exposures in the VHF TV band. The traditional NCRP philosophy of providing a higher standard of protection for members of the general population compared to occupationally exposed individuals, prompted a two-tiered safety standard by which levels of allowable exposure were substantially reduced for "uncontrolled " (e.g., public) and continuous exposures. This measure was taken to account for the fact that workers in an industrial environment are typically exposed no more than eight hours a day while members of the general population in proximity to a source of RF radiation may be exposed continuously. This additional protection factor also provides a greater margin of safety for children, the infirmed, aged, or others who might be more sensitive to RF exposure. After several years of evaluating the national and international scientific and biomedical literature, the members of the NCRP scientific committee selected 931 publications in the peer-reviewed scientific literature on which to base their recommendations. The current NCRP recommendations limit continuous public exposure at PCS frequencies to 1,000 ìW/cm2 . The 1992 ANSI standard was developed by Scientific Coordinating Committee 28 (SCC 28) under the auspices of the Institute of Electrical and Electronic Engineers (IEEE). This standard, entitled "IEEE Standards for Safety Levels with Respect to Human Exposure to Radio Frequency Electromagnetic Fields, 3 kHz to 300 GHz" (IEEE C95.1-1991), was issued in April 1992 and subsequently adopted by ANSI. A complete revision of this standard (C95.1-2005) was completed in October 2005 by SCC 39 the IEEE International Committee on Electromagnetic Safety. The current version, including minor revisions, was published in March 2010. Their recommendations are similar to the NCRP recommendation for the maximum permissible exposure (MPE) to the public PCS frequencies (950 ìW/cm2 for continuous exposure at 1,900 MHz) and incorporates the convention of providing for a greater margin of safety for public as compared with occupational exposure. Higher whole body exposures are allowed for brief periods provided that no 30 minute time-weighted average exposure exceeds these aforementioned limits. On August 9, 1996, the Federal Communications Commission (FCC) established a RF exposure standard that is a hybrid of the current ANSI and NCRP standards. The maximum permissible exposure values used to assess environmental exposures are those of the NCRP (i.e., maximum public continuous exposure at PCS frequencies of 1,000 ìW/cm2 ). The FCC issued these standards in order to address its responsibilities under 2 the National Environmental Policy Act (NEPA) to consider whether its actions will "significantly affect the quality of the human environment.” In as far as there was no other standard issued by a federal agency such as the Environmental Protection Agency (EPA), the FCC utilized their rulemaking procedure to consider which standards should be adopted. The FCC received thousands of pages of comments over a three-year review period from a variety of sources including the public, academia, federal health and safety agencies (e.g., EPA & FDA) and the telecommunications industry. The FCC gave special consideration to the recommendations by the federal health agencies because of their special responsibility for protecting the public health and safety. In fact, the maximum permissible exposure (MPE) values in the FCC standard are those recommended by EPA and FDA. The FCC standard incorporates various elements of the 1992 ANSI and NCRP standards which were chosen because they are widely accepted and technically supportable. There are a variety of other exposure guidelines and standards set by other national and international organizations and governments, most of which are similar to the current ANSI/IEEE or NCRP standard, figure one. The FCC standards “Guidelines for Evaluating the Environmental Effects of Radiofrequency Radiation” (Report and Order FCC 96-326) adopted the ANSI/IEEE definitions for controlled and uncontrolled environments. In order to use the higher exposure levels associated with a controlled environment, RF exposures must be occupationally related (e.g., PCS company RF technicians) and they must be aware of and have sufficient knowledge to control their exposure. All other environmental areas are considered uncontrolled (e.g., public) for which the stricter (i.e., lower) environmental exposure limits apply. All carriers were required to be in compliance with the new FCC RF exposure standards for new telecommunications facilities by October 15, 1997. These standards applied retroactively for existing telecommunications facilities on September 1, 2000. The task for the physical, biological, and medical scientists that evaluate health implications of the RF data base has been to identify those RF field conditions that can produce harmful biological effects. No panel of experts can guarantee safe levels of exposure because safety is a null concept, and negatives are not susceptible to proof. What a dispassionate scientific assessment can offer is the presumption of safety when RF-field conditions do not give rise to a demonstrable harmful effect. Summary & Conclusions This proposed Verizon Wireless telecommunication systems operating with the maximal exposure conditions characteristics as specified above and observing a 27 foot (public) and 14 foot (occupational) exclusion zone directly in front of and at the same elevation as the antenna, will be in full compliance with FCC RF public and occupational safety exposure standards (see appendix A-1). These transmitters, by design and operation, are low-power devices (see attachment 2). An RF safety caution sign, as depicted in appendix A-2 should be placed near the antenna. This sign should contain appropriate contact information and indicate that RF exposures at 14 and 27 feet or closer to the face of the antenna may exceed the FCC occupational and public exposure standards respectively. Thus only qualified RF workers may work within the 27 foot exclusion zone. The maximum RF exposure at ground level and on the roof of surrounding structures from this site will not be in excess of 7.3% and 3.5% of the FCC public safety standard respectively, (see appendix A-3). A chart of the electromagnetic spectrum and a comparison of RF power densities from various common sources is presented in figures two and three respectively in order to place exposures from wireless telecommunications systems in perspective. Given the low levels of radiofrequency fields that would be generated from this Verizon directional antenna installation, there is no scientific basis to conclude that harmful effects will attend the utilization of this proposed wireless telecommunications facility. This conclusion is supported by a large numbers of scientists that have participated in standard-setting activities in the United States who are overwhelmingly agreed that 3 RF radiation exposure below the FCC exposure limits has no demonstrably harmful effects on humans. These findings are based on my professional evaluation of the scientific issues related to the health and safety of non-ionizing electromagnetic radiation and my analysis of the technical specification as provided by Verizon Wireless. The opinions expressed herein are based on my professional judgement and are not intended to necessarily represent the views of any other organization or institution. Please contact me if you require any additional information. Sincerely, Jerrold T. Bushberg Ph.D., DABMP, DABSNM, FAAPM Diplomate, American Board of Medical Physics (DABMP) Diplomate, American Board of Science in Nuclear Medicine (DABSNM) Fellow, American Association of Physicists in Medicine (FAAPM) Fellow, Health Physics Society (FHPS) Enclosures: Figures 1-3; Attachment 1,2; Appendix A-0, A-1, A-2, A-3 and Statement of Experience. 4