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1.
Sensors (Basel) ; 22(5)2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35270864

RESUMO

The electromagnetic field (EMF) in electric vehicles (EVs) affects not only drivers, but also passengers (using EVs daily) and electronic devices inside. This article summarizes the measurement methods applicable in studies of complex EMF in EVs focused on the evaluation of characteristics of such exposure to EVs users and drivers, together with the results of investigations into the static magnetic field (SMF), the extremely low-frequency magnetic field (ELF) and radiofrequency (RF) EMF related to the use of the EVs in urban transportation. The investigated EMF components comply separately with limits provided by international labor law and guidelines regarding the evaluation of human short-term exposure; however other issues need attention-electromagnetic immunity of electronic devices and long-term human exposure. The strongest EMF was found in the vicinity of direct current (DC) charging installations-SMF up to 0.2 mT and ELF magnetic field up to 100 µT-and inside the EVs-up to 30 µT close to its internal electrical equipment. Exposure to RF EMF inside the EVs (up to a few V/m) was found and recognized to be emitted from outdoor radiocommunications systems, together with emissions from sources used inside vehicles, such as passenger mobile communication handsets and antennas of Wi-Fi routers.


Assuntos
Trabalho de Parto , Ondas de Rádio , Eletricidade , Campos Eletromagnéticos , Feminino , Humanos , Gravidez , Meios de Transporte
2.
Sensors (Basel) ; 21(12)2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34205808

RESUMO

The aim of this study was to model and evaluate the Specific Energy Absorption Rate (SAR) values in humans in proximity to fixed multi-antenna I-RFID readers of passive tags under various scenarios mimicking exposure when they are incorporated in Real-Time Location Systems (RTLS), or used to monitor Personal Protective Equipment (PPE). The sources of the electromagnetic field (EMF) in the modelled readers were rectangular microstrip antennas at a resonance frequency in free space of 866 MHz from the ultra-high frequency (UHF) RFID frequency range of 865-868 MHz. The obtained results of numerical modelling showed that the SAR values in the body 5 cm away from the UHF RFID readers need consideration with respect to exposure limits set by international guidelines to prevent adverse thermal effects of exposure to EMF: when the effective radiated power exceeds 5.5 W with respect to the general public/unrestricted environments exposure limits, and with respect to occupational/restricted environments exposure limits, when the effective radiated power exceeds 27.5 W.


Assuntos
Equipamento de Proteção Individual , Dispositivo de Identificação por Radiofrequência , Campos Eletromagnéticos , Humanos , Monitorização Fisiológica
3.
Artigo em Inglês | MEDLINE | ID: mdl-35010336

RESUMO

(1) Background: It has been hypothesised that a significant increase in the use of cardiac magnetic resonance (CMR), for example, when examining COVID-19 convalescents using magnetic resonance imaging (MRI), has an influence the exposure profiles of medical personnel to static magnetic fields (STmf). (2) Methods: Static exposure to STmf (SEmf) was recorded during activities that modelled performing CMR by radiographers. The motion-induced time variability of that exposure (TVEmf) was calculated from SEmf samples. The results were compared with: (i) labour law requirements; (ii) the distribution of vertigo perception probability near MRI magnets; and (iii) the exposure profile when actually performing a head MRI. (3) Results: The exposure profiles of personnel managing 42 CMR scans (modelled using medium (1.5T), high (3T) and ultrahigh (7T) field scanners) were significantly different than when managing a head MRI. The majority of SEmf and TVEmf samples (up to the 95th percentile) were at low vertigo perception probability (SEmf < 500 mT, TVEmf < 600 mT/s), but a small fraction were at medium/high levels; (4) Conclusion: Even under the "normal working conditions" defined for SEmf (STmf < 2T) by labour legislation (Directive 2013/35/EC), increased CMR usage increases vertigo-related hazards experienced by MRI personnel (a re-evaluation of electromagnetic safety hazards is suggested in the case of these or similar changes in work organisation).


Assuntos
COVID-19 , Exposição Ocupacional , Campos Eletromagnéticos/efeitos adversos , Humanos , Imageamento por Ressonância Magnética , Exposição Ocupacional/efeitos adversos , SARS-CoV-2
4.
Sensors (Basel) ; 20(24)2020 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-33322725

RESUMO

The aim of this study was to evaluate the absorption in a user's head of an electromagnetic field (EMF) emitted by the Wi-Fi and/or Bluetooth module of a wearable small Internet of Things (IoT) electronic device (emitting EMF of up to 100 mW), in order to test the hypothesis that EMF has an insignificant influence on humans, and to compare the levels of such EMF absorption in various scenarios when using this device. The modelled EMF source was a meandered inverted-F antenna (MIFA)-type antenna of the ESP32-WROOM-32 radio module used in wearable devices developed within the reported study. To quantify the EMF absorption, the specific energy absorption rate (SAR) values were calculated in a multi-layer ellipsoidal model of the human head (involving skin, fat, skull bones and brain layers). The obtained results show up to 10 times higher values of SAR from the MIFA located in the headband, in comparison to its location on the helmet. Only wearable IoT devices (similar in construction and way of use to the investigated device) emitting at below 3 mW equivalent isotropically radiated power (EIRP) from Wi-Fi/Bluetooth communications modules may be considered environmentally insignificant EMF sources.


Assuntos
Campos Eletromagnéticos , Dispositivos Eletrônicos Vestíveis , Cabeça , Humanos , Internet , Local de Trabalho
5.
Bioelectromagnetics ; 41(7): 500-510, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32726484

RESUMO

The hypothesis being tested was that the exposure of female workers to the electromagnetic field (EMF) emitted by an induction hob (IHb) meeting public exposure limitations (evaluated according to EN/IEC 62233) is also compliant with European Directive 2013/35/EU on workers' protection. The electric field induced in three female models in a realistic ergonomically comfortable posture near IHb was evaluated using numerical models of 25 kHz EMF sources (IHb covered by cooking vessels). It was found that, in analyzed ergonomically comfortable exposure situations, the electric field induced in the user's body may exceed public and workers' limits when the vessels do not match the dimensions of IHb's heating zone. This can even be the case when IHb complies with Conformité Européenne labeling requirements (i.e. EMF exposure falls below public limits 30 cm away from IHb edge). In the 36 exposure scenarios analyzed, statistically significant differences were found when the distances from IHb and vessel dimension, and the height and body mass index of models in exposure scenarios varied, but not between the use of models of pregnant and nonpregnant women. The use of IHb complying with European requirements on general public protection does not ensure that EMF exposure to workers complies with the relevant limits. Adequate protection measures need to address these occupational environmental hazards. © 2020 Bioelectromagnetics Society.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Ergonomia , Campos Magnéticos , Exposição Ocupacional/análise , Exposição à Radiação/análise , Som/efeitos adversos , Feminino , Humanos , Modelos Biológicos , Exposição Ocupacional/efeitos adversos , Postura , Exposição à Radiação/efeitos adversos
6.
Med Pr ; 71(2): 245-253, 2020 Mar 30.
Artigo em Polonês | MEDLINE | ID: mdl-31793558

RESUMO

In 2017, preparations were made in Poland to provide all citizens with access to the Internet at a speed of at least 30 Mb/s, and at a speed of at least 100 Mb/s for 50% of households. This goal is to be realized, among others, by means of the fifth generation (5G) radio-communication networks. This work presents the assumptions of the 5G network structure and estimates of the level of population exposure toelectromagnetic fields related to their rational use. It was also analyzed whether, from the technical point of view, 5G networks could be implemented while respecting the currently acceptable level of electromagnetic field intensity in Poland (7 V/m), taking into account the current environmental exposure caused by antennas of cellular base stations. This is a contribution to the ongoing discussion on the need to change the requirements in Poland in order to limit the level of population exposure to electromagnetic fields. Based on the available documentation of the proposed technical standards, the theoretical analysis of environmental exposure to the electromagnetic field emitted by 5G systems shows that, with rational power management, obtaining the expected (compatible with 5G standards) quality of connections via base stations installed outside of buildings and using intelligent antenna systems with controlled beams, it will be possible to maintain the electric field strength and power density below the current limit values in places accessible to the public (<7 V/m, <0.1 W/m2). Med Pr. 2020;71(2):245-53.


Assuntos
Telefone Celular , Campos Eletromagnéticos , Exposição Ambiental , Humanos , Polônia , Saúde Pública
7.
Med Pr ; 71(1): 105-113, 2020 Jan 20.
Artigo em Polonês | MEDLINE | ID: mdl-31793559

RESUMO

There is an ongoing discussion about electromagnetic hazards in the context of the new wireless communication technology - the fifth generation (5G) standard. Concerns about safety and health hazards resulting from the influence of the electromagnetic field (EMF) emitted by the designed 5G antennas have been raised. In Poland, the level of the population's exposure to EMF is limited to 7 V/m for frequencies above 300 MHz. This limitation results from taking into account the protective measures related not only to direct thermal hazards, but also to diversified indirect and long-term threats. Many countries have not established legal requirements in this frequency range, or they have introduced regulations based on recommendations regarding protection against direct thermal risks only (Council Recommendation 1999/519/EC). For such protection, the permissible levels of electric field intensity are 20-60 V/m (depending on the frequency). This work has been created through an interdisciplinary collaboration of engineers, biologists and doctors, who have been for many years professionally dealing with the protection of the biosphere against the negative effects of EMF. It presents the state of knowledge on the biological and health effects of the EMF emitted by mobile phone devices (including millimeter waves which are planned to be used in the 5G network). A comparison of the EU recommendations and the provisions on public protection being in force in Poland was made against this background. The results of research conducted to date on the biological effects of the EMF radiofrequency emitted by mobile telecommunication devices, operating with the frequencies up to 6 GHz, do not allow drawing any firm conclusions; however, the research evidence is strong enough for the World Health Organization to classify EMF as an environmental factor potentially carcinogenic to humans. At the moment, there is a shortage of adequate scientific data to assess the health effects of exposure to electromagnetic millimeter waves, which are planned to be used in the designed 5G devices. Nevertheless, due to the fact that there are data indicating the existence of biophysical mechanisms of the EMF influence that may lead to adverse health effects, it seems necessary to use the precautionary principle and the ALARA principle when creating environmental requirements for the construction and exploitation of the infrastructure of the planned 5G system. Med Pr. 2020;71(1):105-13.


Assuntos
Campos Eletromagnéticos , Exposição Ambiental , Saúde da População , Ondas de Rádio , Telefone Celular , Humanos , Polônia
8.
Sensors (Basel) ; 19(17)2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31466315

RESUMO

The aim of this study was to model the absorption in the head of an electromagnetic field (EMF) emitted by a radiofrequency identification reader operating at a frequency of 13.56 MHz (recognized as an RFID HF reader), with respect to the direct biophysical effects evaluated by the specific absorption rate (SAR), averaged over the entire head or locally, over any 10 g of tissues. The exposure effects were compared between the head of a user of a hearing implant with an acoustic sensor and a person without such an implant, used as a referenced case. The RFID HF reader, such as is used in shops or libraries, was modeled as a loop antenna (35 × 35 cm). SAR was calculated in a multi-layer ellipsoidal model of the head-with or without models of hearing implants of two types: Bonebridge (MED-EL, Austria) or bone anchored hearing aid attract (BAHA) (Cochlear, Sweden). Relative SAR values were calculated as the ratio between the SAR in the head of the implant user and the non-user. It was found that the use of BAHA hearing implants increased the effects of 13.56 MHz EMF exposure in the head in comparison to non-user-up to 2.1 times higher localized SAR in the worst case exposure scenario, and it is statistically significant higher than when Bonebridge implants are used (Kruscal-Wallis test with Bonferroni correction, p < 0.017). The evaluation of EMF exposure from an RFID reader with respect to limits established for the implant non-user population may be insufficient to protect an implant user when exposure approaches these limits, but the significant difference between exposure effects in users of various types of implants need to be considered.


Assuntos
Campos Eletromagnéticos , Cabeça/fisiologia , Auxiliares de Audição , Dispositivo de Identificação por Radiofrequência , Telefone Celular , Humanos , Próteses e Implantes
9.
Sensors (Basel) ; 20(1)2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31905869

RESUMO

The aim is to evaluate specific absorption rate (SAR) values from exposure near handheld ultra-high frequency radiofrequency identification readers (UHF RFID guns-small electronic devices, or even portable computers with relevant accessories-emitting up to several watts of electromagnetic field (EMF) to search for RFID sensors (tags) attached to marked objects), in order to test the hypothesis that they have an insignificant environmental influence. Simulations of SAR in adult male and female models in seven exposure scenarios (gun near the head, arm, chest, hip/thigh of the operator searching for tags, or near to the chest and arm of the scanned person or a bystander). The results showed EMF exposure compliant with SAR limits for general public exposure (ICNIRP/European Recommendation 1999/519/EC) at emissions up to 1 W (reading range 3.5-11 m, depending on tag sensitivity). In the worst-case scenario, guns with a reading range exceeding 5 m (>2 W emission) may cause an SAR exceeding the general public limits in the palm of the user and the torso of the user, a bystander, or a scanned person; occupational exposure limits may be exceeded when emission >5 W. Users of electronic medical implants and pregnant women should be treated as individuals at particular risk in close proximity to guns, even at emissions of 1 W. Only UHF RFID guns emitting below 1 W may be considered as environmentally insignificant EMF sources.

11.
Int J Occup Med Environ Health ; 31(6): 795-808, 2018 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-30520435

RESUMO

OBJECTIVES: Electromagnetic fields (EMF) may cause malfunctions in electronic devices, in particular in active implantable medical devices (AIMD), along with discomfort or health hazards to users. The use of AIMD by workers is increasing (especially cardiac pacemakers, implantable cardioverter defibrillators and wearable insulin infusion pumps). Electromagnetic fields may be much stronger in the working environment than applied in basic immunity tests of AIMD (based on EN 60601- 1-2:2015 and EN 50527-1:2016). European Directive 2013/35/EU regarding the safety of workers exposed to EMF considered the AIMD users to be "workers at particular risk" who need an individual evaluation of EMF hazards. The study aimed at evaluating the safety of users of AIMD in medical and industrial working environments exposed to EMF. MATERIAL AND METHODS: Near the common sources of strong EMF applied in medical and industrial use, the "standard safety distances" (SSD) for AIMD users were evaluated (i.e., distances from the EMF source, where exposure drops below limits from Recommendation 1999/519/EC and AIMD safety may be expected). The analysis is based on the results of measurements of magnetic and electric field strengths near 127 typical devices, in their normal use. RESULTS: The longest electric field related SSD was identified near dielectric sealers (up to 180 cm), and the longest magnetic field related SSD - near induction heaters (up to 450 cm). CONCLUSIONS: Electromagnetic fields related AIMD malfunctions need to be considered up to several meters from EMF sources. The "individual safety distance," that is sufficient to ensure the safety of a particular AIMD user may be significantly different (usually shorter) from the presented SSD, but needs to be considered in the context of detailed safety data from the AIMD manufacturer (if available). The labelling indicating the location of the area of a strong EMF increases safety of AIMD users in the work environment. Int J Occup Med Environ Health 2018;31(6):795-808.


Assuntos
Desfibriladores Implantáveis/normas , Equipamentos e Provisões Elétricas/normas , Campos Eletromagnéticos/efeitos adversos , Guias como Assunto , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/normas , Local de Trabalho/normas , Adulto , Falha de Equipamento , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Segurança
13.
Int J Radiat Biol ; 94(10): 926-933, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29265909

RESUMO

PURPOSE: The aim was to model the effects of exposure to a low or intermediate frequency electromagnetic field (LIF-EMF), characterized by the electric field induced in the body, in order to evaluate how the type of insulin needle and the way it is injected influences the exposed user of a wearable insulin pump. MATERIAL AND METHODS: Numerical models of exposure scenarios (sources of LIF-EMF, with a dominant magnetic component: 50Hz-1MHz; the insulin needle type; the way it is injected and insulin pump user) were worked out. The influence of the insulin needle on the user's safety (the ratio of the induced electric field in tissues surrounding the needle and tissues of a person without an injection, both exposed identically) were calculated. RESULTS: The effects of LIF-EMF exposure in insulin pump users were found to be up to approximately 7-times higher, varying with statistically significance (p < .05) with the material of the needle, the way it is injected and the polarization of the affecting magnetic field. CONCLUSIONS: When steel insulin needles is used, the assessment of user's EMF exposure should be carried out using magnetic field limits at least 5-times lower than given in general international requirements.


Assuntos
Simulação por Computador , Sistemas de Infusão de Insulina , Campos Magnéticos , Dispositivos Eletrônicos Vestíveis , Injeções , Campos Magnéticos/efeitos adversos , Agulhas , Segurança
14.
Biomed Res Int ; 2017: 5785482, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28758119

RESUMO

OBJECTIVES: The aim was to evaluate correlations between biophysical effects of 27 MHz electromagnetic field exposure in humans (limb induced current (LIC)) and (1) parameters of affecting heterogeneous electric field and (2) body anthropometric properties, in order to improve the evaluation of electromagnetic environmental hazards. METHODS: Biophysical effects of exposure were studied in situ by measurements of LIC in 24 volunteers (at the ankle) standing near radio communication rod antenna and in silico in 4 numerical body phantoms exposed near a model of antenna. RESULTS: Strong, positive, statistically significant correlations were found in all exposure scenarios between LIC and body volume index (body height multiplied by mass) (r > 0.7; p < 0.001). The most informative exposure parameters, with respect to the evaluation of electromagnetic hazards by measurements (i.e., the ones strongest correlated with LIC), were found to be the value of electric field (unperturbed field, in the absence of body) in front of the chest (50 cm from body axis) or the maximum value in space occupied by human. Such parameters were not analysed in previous studies. CONCLUSIONS: Exposed person's body volume and electric field strength in front of the chest determine LIC in studied exposure scenarios, but their wider applicability needs further studies.


Assuntos
Simulação por Computador , Extremidades , Modelos Biológicos , Ondas de Rádio/efeitos adversos , Humanos
15.
Med Pr ; 68(4): 469-477, 2017 Jun 27.
Artigo em Polonês | MEDLINE | ID: mdl-28655937

RESUMO

BACKGROUND: Low frequency magnetic field, inducing electrical field (Ein) inside conductive structures may directly affect the human body, e.g., by electrostimulation in the nervous system. In addition, the spatial distribution and level of Ein are disturbed in tissues neighbouring the medical implant. MATERIAL AND METHODS: Numerical models of magneto-therapeutic applicator (emitting sinusoidal magnetic field of frequency 100 Hz) and the user of hearing implant (based on bone conduction: Bonebridge type - IS-BB or BAHA (bone anchorde hearing aid) type - IS-BAHA) were worked out. Values of Ein were analyzed in the model of the implant user's head, e.g., physiotherapist, placed next to the applicator. RESULTS: It was demonstrated that the use of IS-BB or IS-BAHA makes electromagnetic hazards significantly higher (up to 4-fold) compared to the person without implant exposed to magnetic field heterogeneous in space. Hazards for IS-BAHA users are higher than those for IS-BB users. It was found that applying the principles of directive 2013/35/EU, at exposure to magnetic field below exposure limits the direct biophysical effects of exposure in hearing prosthesis users may exceed relevant limits. Whereas applying principles and limits set up by Polish labor law or the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines, the compliance with the exposure limits also ensures the compliance with relevant limits of electric field induced in the body of hearing implant user. CONCLUSIONS: It is necessary to assess individually electromagnetic hazard concerning hearing implant users bearing in mind significantly higher hazards to them compared to person without implant or differences between levels of hazards faced by users of implants of various structural or technological solutions. Med Pr 2017;68(4):469-477.


Assuntos
Condução Óssea , Implantes Cocleares/efeitos adversos , Campos Eletromagnéticos , Exposição à Radiação , Humanos , Modelos Teóricos
16.
MAGMA ; 30(3): 255-264, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27981395

RESUMO

OBJECTIVE: To assess the individual exposure to the static magnetic field (SMF) and the motion-induced time-varying magnetic field (TVMF) generated by activities in an inhomogeneous SMF near high and ultra-high field magnetic resonance imaging (MRI) scanners. The study provides information on the level of exposure to high and ultra-high field MRI scanners during research activities. MATERIALS AND METHODS: A three-axis Hall magnetometer was used to determine the SMF and TVMF around human 3- and 7-Tesla (T) MRI systems. The 7-T MRI scanner used in this study was passively shielded and the 3-T scanner was actively shielded and both were from the same manufacturer. The results were compared with the exposure restrictions given by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). RESULTS: The recorded exposure was highly variable between individuals, although they followed the same instructions for moving near the scanners. Maximum exposure values of B = 2057 mT and dB/dt = 4347 mT/s for the 3-T scanner and B = 2890 mT, dB/dt = 3900 mT/s for 7 T were recorded. No correlation was found between reporting the MRI-related sensory effects and exceeding the reference values. CONCLUSIONS: According to the results of our single-center study with five subjects, violation of the ICNIRP restrictions for max B in MRI research environments was quite unlikely at 3 and 7 T. Occasions of exceeding the dB/dt limit at 3 and 7 T were almost similar (30% of 60 exposure scenarios) and highly variable among the individuals.


Assuntos
Campos Magnéticos , Imageamento por Ressonância Magnética , Magnetometria/métodos , Exposição Ocupacional/análise , Exposição à Radiação/análise , Monitoramento de Radiação/métodos , Humanos , Radiologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Electromagn Biol Med ; 34(3): 265-73, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26444204

RESUMO

Antennas from various wireless communications systems [e.g. mobile phones base transceiver stations (BTS) and handsets used by passengers, public Internet access, staff radiophone transmitters used between engine-drivers and traffic operators] emitting radiofrequency electromagnetic radiation (RF-EMR) are used inside underground metro public transportation. Frequency-selective exposimetric investigations of RF-EMR exposure inside the metro infrastructure in Warsaw (inside metro cars passing between stations and on platforms) were performed. The statistical parameters of exposure to the E-field were analyzed for each frequency range and for a total value (representing the wide-band result of measurements of complex exposure). The recorded exposimetric profiles showed the dominant RF-EMR sources: handsets and BTS of mobile communication systems (GSM 900 and UMTS 2100) and local wireless Internet access (WiFi 2G). Investigations showed that the GSM 900 system is the dominant source of exposure - BTS (incessantly active) on platforms, and handsets - used by passengers present nearby during the tube drive. The recorded E-field varies between sources (for BTS were: medians - 0.22 V/m and 75th percentile - 0.37 V/m; and for handsets: medians - 0.28 V/m and 75th percentile - 0.47 V/m). Maximum levels (peaks) of exposure recorded from mobile handsets exceeded 10 V/m (upper limit of used exposimeters). Broadband measurements of E-field, including the dominant signal emitted by staff radiophones (151 MHz), showed that the level of this exposure of engine-drivers does not exceed 2.5 V/m.


Assuntos
Campos Eletromagnéticos , Exposição à Radiação/análise , Ondas de Rádio , Meios de Transporte/instrumentação , Polônia , Tecnologia sem Fio/instrumentação
18.
Biomed Res Int ; 2015: 272460, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25879021

RESUMO

The use of radiofrequency (98-2450 MHz range) personal exposimeters to measure the electric field (E-field) in far-field exposure conditions was modelled numerically using human body model Gustav and finite integration technique software. Calculations with 256 models of exposure scenarios show that the human body has a significant influence on the results of measurements using a single body-worn exposimeter in various locations near the body ((from -96 to +133)%, measurement errors with respect to the unperturbed E-field value). When an exposure assessment involves the exposure limitations provided for the strength of an unperturbed E-field. To improve the application of exposimeters in compliance tests, such discrepancies in the results of measurements by a body-worn exposimeter may be compensated by using of a correction factor applied to the measurement results or alternatively to the exposure limit values. The location of a single exposimeter on the waist to the back side of the human body or on the front of the chest reduces the range of exposure assessments uncertainty (covering various exposure conditions). However, still the uncertainty of exposure assessments using a single exposimeter remains significantly higher than the assessment of the unperturbed E-field using spot measurements.


Assuntos
Modelos Biológicos , Equipamento de Proteção Individual , Exposição à Radiação/análise , Monitoramento de Radiação/instrumentação , Ondas de Rádio , Contagem Corporal Total/instrumentação , Telefone Celular , Simulação por Computador , Campos Eletromagnéticos , Desenho de Equipamento , Análise de Falha de Equipamento , Fidelidade a Diretrizes , Micro-Ondas , Monitorização Ambulatorial/instrumentação , Doses de Radiação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
19.
Int J Occup Med Environ Health ; 27(6): 1043-54, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25519944

RESUMO

OBJECTIVES: The aim of the study was to identify and assess electromagnetic radiofrequency radiation (EMRR) exposure in a workplace located in a publicly accessible environment, and represented by offices (where exposure is caused by various transmitters of local fixed indoor and outdoor wireless communication systems). MATERIAL AND METHODS: The investigations were performed in 45 buildings (in urban and rural areas in various regions of Poland), using frequency-selective electric field strength (E-field) exposimeters sensitive to the EMRR with a frequency range of 88-2500 MHz, split into 12 sub-bands corresponding to the operating frequencies of typical EMRR sources. The variability of the E-field was analyzed for each frequency range and the total level of exposure by statistical parameters of recorded exposimetric profiles: minimum, maximum, median values and 25-75th - percentiles. RESULTS: The main sources of exposure to EMRR are mobile phone base transceiver stations (BTS) and radio-television transmitters (RTV). The frequency composition in a particular office depends on the building's location. The E-field recorded in buildings in urban and rural areas from the outdoor BTS did not exceed respectively: medians - 0.19 and 0.05 V/m, 75th percentiles -0.25 and 0.09 V/m. In buildings equipped with the indoor BTS antennas the E-field did not exceed: medians - 1 V/m, 75th percentiles - 1.8 V/m. Whereas in urban and rural areas, the median and 75th percentile values of the E-field recorded in buildings located near the RTV (within 1 km) did not exceed: 1.5 and 3.8 V/m or 0.4 and 0.8 V/m, for radio FM band or for TV bands, respectively. CONCLUSIONS: Investigations confirmed the practical applicability of the exposimetric measurements technique for evaluating parameters of worker's exposure in both frequency- and time-domain. The presented results show EMRR exposure of workers or general public in locations comparable to offices to be well below international limits.


Assuntos
Radiação Eletromagnética , Exposição Ocupacional/análise , Radiometria/instrumentação , Tecnologia sem Fio , Telefone Celular , Exposição Ambiental/análise , Humanos , Rádio , Televisão , Local de Trabalho
20.
Med Pr ; 65(3): 351-60, 2014.
Artigo em Polonês | MEDLINE | ID: mdl-25230564

RESUMO

BACKGROUND: Thermal effects of radiofrequency electromagnetic fields (REMF) exposure of humans may be assessed by calculations of the parameter recognized as SAR (specific energy absorption rate) in virtual human body models, which actually do not represent anthropometric properties of the entire population. Therefore, it is important to determine the relations between SAR values and anthropometric parameters that enable individualization of SAR estimation independently of body properties of a given person. MATERIAL AND METHODS: The analysis concerned 48 exposure scenarios of 4 virtual body models (male and female) to vertically or horizontally polarized REMF of 27 MHz or 100 MHz frequency of various directions of propagation. RESULTS: In the subgroup of results 100 MHz/vertical polarization statistically significant (strong; p < 0.05) correlations were identified between SAR averaged in the whole body and height, mass, BMI, circumference of chest, waist, neck and frontal cross-section area, and between local SAR in head and neck and the height, mass, circumference of chest waist or neck and frontal cross-section area. Identified relations and SAR in the Gustav model were used to estimate the variety of SAR in Polish population of adults (5-95. percentile of female and male): +/- 30% for SAR averaged in the whole body, +/- 50% for localized SAR. CONCLUSIONS: It was demonstrated that in the preliminary classified type of assessed REMF exposure (e.g., in terms of field polarization and frequency) it is possible to identify statistical relations between various SAR parameters and anthropometric properties of the exposed body. Related quantities can be used for individualized assessment of worker's electromagnetic hazards.


Assuntos
Absorciometria de Fóton , Antropometria/métodos , Campos Eletromagnéticos , Modelos Biológicos , Ondas de Rádio , Irradiação Corporal Total , Adulto , Algoritmos , Simulação por Computador , Feminino , Humanos , Masculino , Exposição Ocupacional , Doses de Radiação , Valores de Referência
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