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1.
Radiat Prot Dosimetry ; 199(8-9): 818-825, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37225206

RESUMO

ICNIRP 2020 guidelines for limiting exposure to radiofrequency fields replace the radiofrequency part of the ICNIRP 1998 guidelines for limiting exposure to time-varying electric, magnetic and electromagnetic fields. Besides setting new restrictions that prevent thermal effect they also took over the 100 kHz to 10 MHz part of the ICNIRP 2010 guidelines for limiting exposure to low-frequency electromagnetic fields, which provides restrictions that prevent nerve stimulation effect. The latest guidelines brought many changes to the system of protection against exposure to radiofrequency fields starting with the physical quantities used to express restrictions and continuing with specific restrictions and new exposure metrics employed. For the first time, the case of brief local exposure to intense radiofrequency fields was accounted by ICNIRP for setting new types of exposure restrictions. All these changes led to more detailed and complex guidelines, but their provisions are more difficult to apply in practice. Our paper presents some of the challenges related to the use in practice of the new ICNIRP restrictions for human exposure to radiofrequency fields.


Assuntos
Campos Eletromagnéticos , Ondas de Rádio , Humanos , Ondas de Rádio/efeitos adversos
2.
Bioelectromagnetics ; 40(7): 498-511, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31522469

RESUMO

Despite much research, gaps remain in knowledge about the potential health effects of exposure to radiofrequency (RF) fields. This study investigated the effects of early-life exposure to pulsed long term evolution (LTE) 1,846 MHz downlink signals on innate mouse behavior. Animals were exposed for 30 min/day, 5 days/week at a whole-body average specific energy absorption rate (SAR) of 0.5 or 1 W/kg from late pregnancy (gestation day 13.5) to weaning (postnatal day 21). A behavioral tracking system measured locomotor, drinking, and feeding behavior in the home cage from 12 to 28 weeks of age. The exposure caused significant effects on both appetitive behaviors and activity of offspring that depended on the SAR. Compared with sham-exposed controls, exposure at 0.5 W/kg significantly decreased drinking frequency (P ≤ 0.000) and significantly decreased distance moved (P ≤ 0.001). In contrast, exposure at 1 W/kg significantly increased drinking frequency (P ≤ 0.001) and significantly increased moving duration (P ≤ 0.005). In the absence of other plausible explanations, it is concluded that repeated exposure to low-level RF fields in early life may have a persistent and long-term effect on adult behavior. Bioelectromagnetics. 2019;40:498-511. © 2019 The Authors. Bioelectromagnetics Published by Wiley Periodicals, Inc.


Assuntos
Efeitos Tardios da Exposição Pré-Natal , Ondas de Rádio/efeitos adversos , Animais , Comportamento Animal/efeitos da radiação , Peso Corporal/efeitos da radiação , Simulação por Computador , Feminino , Aprendizagem/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Fatores de Tempo , Irradiação Corporal Total
3.
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
4.
Environ Res ; 154: 160-170, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28086101

RESUMO

Historically, assessment of human exposure to electric and magnetic fields has focused on the extremely-low-frequency (ELF) and radiofrequency (RF) ranges. However, research on the typically emitted fields in the intermediate-frequency (IF) range (300Hz to 1MHz) as well as potential effects of IF fields on the human body remains limited, although the range of household appliances with electrical components working in the IF range has grown significantly (e.g., induction cookers and compact fluorescent lighting). In this study, an extensive measurement survey was performed on the levels of electric and magnetic fields in the IF range typically present in residences as well as emitted by a wide range of household appliances under real-life circumstances. Using spot measurements, residential IF field levels were found to be generally low, while the use of certain appliances at close distance (20cm) may result in a relatively high exposure. Overall, appliance emissions contained either harmonic signals, with fundamental frequencies between 6kHz and 300kHz, which were sometimes accompanied by regions in the IF spectrum of rather noisy, elevated field strengths, or much more capricious spectra, dominated by 50Hz harmonics emanating far in the IF domain. The maximum peak field strengths recorded at 20cm were 41.5V/m and 2.7A/m, both from induction cookers. Finally, none of the appliance emissions in the IF range exceeded the exposure summation rules recommended by the International Commission on Non-Ionizing Radiation Protection guidelines and the International Electrotechnical Commission (IEC 62233) standard at 20cm and beyond (maximum exposure quotients EQE 1.0 and EQH 0.13).


Assuntos
Campos Eletromagnéticos/efeitos adversos , Exposição Ambiental/efeitos adversos , Habitação , Iluminação/efeitos adversos , Campos Magnéticos/efeitos adversos , Bélgica , Monitoramento Ambiental , Humanos , Eslovênia , Reino Unido
5.
Int J Occup Saf Ergon ; 12(2): 149-53, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16790172

RESUMO

The aim of this study is to investigate the levels of electric and magnetic power frequency fields at 8 electrical transformation stations in the North-East counties of Romania and to check their compliance with standards. Spot measurements were carried out on both electric and magnetic fields under overhead conductors of 110-, 220- and 380-kV installations. The magnetic field levels were several orders of magnitude below the reference level for occupational exposure set by ICNIRP (International Commission on Non-Ionizing Radiation) or by Romanian regulations. In contrast, the electric field levels were about the same order of magnitude as the reference levels. In 2 electrical stations the reference level of 10 kV/m was exceeded at specific locations within the outdoor installations area. However, the additional reference level for short-time exposure included in Romanian regulations, 30 kV/m, was not exceeded.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Exposição Ocupacional/análise , Eletricidade/efeitos adversos , Regulamentação Governamental , Fidelidade a Diretrizes , Humanos , Agências Internacionais , Exposição Ocupacional/legislação & jurisprudência , Exposição Ocupacional/prevenção & controle , Monitoramento de Radiação , Romênia , Local de Trabalho/legislação & jurisprudência , Local de Trabalho/normas
6.
Health Phys ; 84(6): 770-3, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12822587

RESUMO

This paper proposes a method for making a transition between discontinuous magnetic-field limit values set by exposure standards in adjacent frequency ranges. This method is applied to the limit values set by the International Commission on Non-Ionizing Radiation Protection for static and extremely low frequency magnetic fields. In this case, both ceiling and time-weighted average values are provided for static fields, but only ceiling limits are provided for extremely low frequency fields. The proposed method of setting both types of limit values for magnetic fields between 0 and 1 Hz can contribute to achieving exposure standards that have continuity on the entire frequency spectrum. As far as it eliminates discontinuities, it will also help the implementation of regulations by eliminating some uncertainties. Therefore, it could reduce difficulties in checking compliance with standards.


Assuntos
Campos Eletromagnéticos , Modelos Biológicos , Exposição Ocupacional/normas , Radiometria/métodos , Radiometria/normas , Humanos , Classificação Internacional de Doenças , Cooperação Internacional , Concentração Máxima Permitida , Exposição Ocupacional/prevenção & controle , Saúde Ocupacional , Doses de Radiação
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