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1.
Bioelectromagnetics ; 44(3-4): 71-76, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37002551

RESUMO

Power density and duty factor values were measured around smart utility meters operating at 868 MHz under laboratory-controlled conditions. The maximum 6-min averaged exposure recorded was 0.1 mWm-2 , which is less than 0.0024% of the corresponding 1998 ICNIRP general public reference level. Duty factors measured were less than 2.8%. This study found that the exposure contribution from Zigbee smart meter devices operating at 868 MHz is generally lower than, if not similar to, those operating at 2.4 GHz. © 2023 Crown copyright. Bioelectromagnetics published by Wiley Periodicals LLC on behalf of Bioelectromagnetics Society.


Assuntos
Campos Eletromagnéticos , Ondas de Rádio , Exposição Ambiental
3.
Bioelectromagnetics ; 39(3): 200-216, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29143352

RESUMO

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. Bioelectromagnetics. 39:200-216, 2018. © 2017 Wiley Periodicals, Inc.


Assuntos
Eletricidade , Campos Eletromagnéticos , Exposição à Radiação/análise , Ondas de Rádio , Absorção de Radiação , Criança , Humanos
4.
Bioelectromagnetics ; 38(4): 280-294, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28324620

RESUMO

Laboratory measurements of electric fields have been carried out around examples of smart meter devices used in Great Britain. The aim was to quantify exposure of people to radiofrequency signals emitted from smart meter devices operating at 2.4 GHz, and then to compare this with international (ICNIRP) health-related guidelines and with exposures from other telecommunication sources such as mobile phones and Wi-Fi devices. The angular distribution of the electric fields from a sample of 39 smart meter devices was measured in a controlled laboratory environment. The angular direction where the power density was greatest was identified and the equivalent isotropically radiated power was determined in the same direction. Finally, measurements were carried out as a function of distance at the angles where maximum field strengths were recorded around each device. The maximum equivalent power density measured during transmission around smart meter devices at 0.5 m and beyond was 15 mWm-2 , with an estimation of maximum duty factor of only 1%. One outlier device had a maximum power density of 91 mWm-2 . All power density measurements reported in this study were well below the 10 W m-2 ICNIRP reference level for the general public. Bioelectromagnetics. 2017;38:280-294. © 2017 Crown copyright. BIOELECTROMAGNETICS © 2017 Wiley Periodicals, Inc.


Assuntos
Eletricidade , Campos Eletromagnéticos , Laboratórios , Exposição à Radiação/análise , Calibragem , Humanos , Ondas de Rádio , Software , Incerteza
5.
Bioelectromagnetics ; 36(8): 603-12, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26508012

RESUMO

Dielectric properties of freshly excised human liver tissues (in vitro) with several pathological conditions including cancer were obtained in frequency range 100 MHz-5 GHz. Differences in dielectric behavior of normal and pathological tissues at microwave frequencies are discussed based on histological information for each tissue. Data presented are useful for many medical applications, in particular nanosecond pulsed electroporation techniques. Knowledge of dielectric properties is vital for mathematical calculations of local electric field distribution inside electroporated tissues and can be used to optimize the process of electroporation for treatment planning procedures.


Assuntos
Fígado/patologia , Neoplasias/patologia , Idoso , Impedância Elétrica , Feminino , Humanos , Fígado/citologia , Masculino , Pessoa de Meia-Idade
7.
Prog Biophys Mol Biol ; 107(3): 434-8, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21906617

RESUMO

This paper reviews and summarises the state of knowledge on dielectric properties of tissues; in particular those obtained as a function of age. It also examines the impact of variation in dielectric data on the outcome of recent dosimetric studies assessing the exposure of children to electromagnetic fields.


Assuntos
Envelhecimento/efeitos da radiação , Campos Eletromagnéticos/efeitos adversos , Exposição Ambiental/efeitos adversos , Ondas de Rádio/efeitos adversos , Animais , Criança , Impedância Elétrica , Humanos , Telecomunicações
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