ID Number		1405
Study Type		Engineering & Physics
Model		RF emission levels from environmental sources: RF broadcast towers, mobile phone base stations and smart meters.
Details		Authors' abstract: Tell et al. 2012 (IEEE #5166): This study examined radiofrequency (RF) emissions from smart electric power meters deployed in two service territories in California for the purpose of evaluating potential human exposure. These meters included transmitters operating in a local area mesh network (RF LAN, <250 mW); a cell relay, which uses a wireless wide area network (WWAN, <1 W); and a transmitter serving a home area network (HAN, <70 mW). In all instances, RF fields were found to comply by a wide margin with the RF exposure limits established by the US Federal Communications Commission. The study included specialised measurement techniques and reported the spatial distribution of the fields near the meters and their duty cycles (typically <1 %) whose value is crucial to assessing time-averaged exposure levels. This study is the first to characterise smart meters as deployed. However, the results are restricted to a single manufacturer's emitters. AUTHORS' ABSTRACT: Foster and Tell 2013 (IEEE #5243): This paper reviews radiofrequency (RF) field levels produced by electric utility meters equipped with RF transceivers (so-called Smart Meters), focusing on meters from one manufacturer (Trilliant, Redwood City, CA, USA, and Granby, QC, Canada). The RF transmission levels are summarized based on publicly available data submitted to the U.S. Federal Communications Commission supplemented by limited independent measurements. As with other Smart Meters, this meter incorporates a low powered radiofrequency transceiver used for a neighborhood mesh network, in the present case using ZigBee-compliant physical and medium access layers, operating in the 2.45 GHz unlicensed band but with a proprietary network architecture. Simple calculations based on a free space propagation model indicate that peak RF field intensities are in the range of 10 mW m or less at a distance of more than 1-2 m from the meters. However, the duty cycle of transmission from the meters is very low (< 1%). Limited measurements identified pulses from the meter that were consistent with data reported by the vendor to the U.S. Federal Communications Commission. Limited measurements conducted in two houses with the meters were unable to clearly distinguish emissions from the meters from the considerable electromagnetic clutter in the same frequency range from other sources, including Wi-Fi routers and, when it was activated, a microwave oven. These preliminary measurements disclosed the difficulties that would be encountered in characterizing the RF exposures from these meters in homes in the face of background signals from other household devices in the same frequency range. An appendix provides an introduction to Smart Meter technology. The RF transmitters in wireless-equipped Smart Meters operate at similar power levels and in similar frequency ranges as many other digital communications devices in common use, and their exposure levels are very far below U.S. and international exposure limits. AUTHORS' ABSTRACT: Tell and Kavet 2014 (IEEE #5776): In 1980, Tell and Mantiply published a study of radiofrequency (RF) fields measured across 15 major metropolitan areas in the USA. They required a van fully equipped with instrumentation and computing capability for their measurements. This study aimed to assess whether and how hand-held instrumentation available today would facilitate and enhance the efficiency of large-scale surveys of ambient RF fields. In addition, the data would provide a suggestion as to how the profile of ambient RF fields has changed with respect to frequency content and magnitude. Not unexpectedly, the relative power densities were orders of magnitude lower than the Federal Communications Commission's (FCC) maximum permissible exposure (MPE) for the general public, with a maximum time-averaged value across the VHF-FM-UHF-cellular bands of 0.12 % of the MPE (AM's contribution was negligible). In both the 1980 and the present study, the power density in the FM band was a major contributor to overall power density, but over time, power densities in the VHF and UHF band decreased and increased, respectively. From the perspective of absolute power density, the wideband values in the 1980 study, this study and any number of assessments conducted in European nations are not generally different from one another. AUTHORS' ABSTRACT: Qureshi et al. 2017 (IEEE #6872): Human body exposure to radiofrequency electromagnetic waves emitted from smart meters was assessed using various exposure configurations. Specific energy absorption rate distributions were determined using three anatomically realistic human models. Each model was assigned with age- and frequency-dependent dielectric properties representing a collection of age groups. Generalized exposure conditions involving standing and sleeping postures were assessed for a home area network operating at 868 and 2,450 MHz. The smart meter antenna was fed with 1 W power input which is an overestimation of what real devices typically emit (15 mW max limit). The highest observed whole body specific energy absorption rate value was 1.87 mW kg-1 , within the child model at a distance of 15 cm from a 2,450 MHz device. The higher values were attributed to differences in dimension and dielectric properties within the model. Specific absorption rate (SAR) values were also estimated based on power density levels derived from electric field strength measurements made at various distances from smart meter devices. All the calculated SAR values were found to be very small in comparison to International Commission on Non-Ionizing Radiation Protection limits for public exposure. AUTHORS' CONCLUSIONS (in part): Tell and Tell, 2013 (IEEE #6962): A number of field measurement studies conducted by one of the authors address RF emissions from wireless smart meters [1, 2, 3, 9, 15]. All of these studies have demonstrated that the potential exposures that could result from proximity to the subject smart meter emissions comply with the limits set by the FCC. This study is no different. The RF emissions produced by the smart meters deployed by GMP and BED were found to comply with the public exposure regulations of the FCC by a wide margin, typically by a factor of approximately 1500 times, even at one foot from the meters. The measurement data show that the RF field emissions decrease sharply with increasing distance from the smart meters. At distances more likely associated with common day-to-day exposures to smart meter emissions, the RF fields become even dramatically less. For example, at a distance of 10 feet in front of a meter, the RF field drops to approximately 76,000 times less than the FCC limit. Relative to the actual biological hazard thresholds, not the MPE which contains a safety factor of 50 for the general public, the RF fields at one foot and ten feet from a smart meter are some 75,000 times and 3,800,000 times less respectively. AUTHORS' ABSTRACT: Tell, Kavet and Mezei,2013 (IEEE #6963): This study presents measurement data that describe radiofrequency emission levels and patterns from smart meters (rated nominally at 1W) currently deployed in Pacific Gas and Electric Companys service territory in northern California. The smart meters in our investigation could not be set to operate continuously and required a Field Service Unit to induce short periods of emitted fields. To obtain peak field data under both laboratory and ambient conditions, a spectrum analyzer scanned across the 83 transmitting channels between 902 and 928 MHz used by the smart meter on a random frequency-hopping basis. To obtain data describing temporal emission patterns, the analyzer operated in scope mode. Duty cycle was estimated using transmit data acquired by the system operator from over 88,000 m. Instantaneous peak fields at 0.3m in front of the meters were no more than 15% of the US Federal Communications Commission (FCC) exposure limit for the general public, and 99.9% of the meters operated with a duty cycle of 1.12% or less during the sampling period. In a sample of measurements in six single-detached residences equipped with individual smart meters, no interior measurement of peak field exceeded 1% of the FCCs general public exposure limit.
Findings		Not Applicable to Bioeffects
Status		Completed With Publication
Principal Investigator		Consultant, Las Vegas, NV, USA
Funding Agency		?????
Country		UNITED STATES
References		Tell, RA et al. IEEE Eng. Med. Biology., (1995) 14:650-651 Tell, RA et al. Proc. IEEE, (1980) 68:6-12 Janes, DE et al. Radio Sci., (1977) 12:49-56 Tell, RA Report, (1976) :- Tell, RA et al. Radiation Protection Dosimetry. , (2012) 151:17-29 Foster, KR et al. Health Physics., (2013) 105:177-186 Tell, RA et al. Radiat Prot Dosimetry., (2014) 162:499-507 Qureshi, MRA et al. Bioelectromagnetics., (2018) 39:200-216 Tell, RA et al. Report Prepared for The Department of Public Service, 112 State Street, Montpelier, VT 05620-2601., (2013) :-149 pages Tell, RA et al. Journal of Exposure Science and Environmental Epidemiology., (2013) 23:549-553
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