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1.
Health Phys ; 125(3): 202-206, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37195187

RESUMO

ABSTRACT: Pacemakers (PM) and implantable cardioverter defibrillators (ICD) are active implantable medical devices (AIMD) needed in case of cardiac arrhythmias. Given their potentially life-sustaining nature, the interaction between any source of electromagnetic field and these AIMDs is an ongoing concern of patients, industry, and regulators. According to the current regulatory framework, the required immunity of PM and ICD provides a reasonable unperturbed behavior in the presence of cell phones and base stations that use pre-5G technologies. PM/ICD international standards do not consider some peculiar characteristics of 5G technology and some of the 5G technology frequency bands (those above 3 GHz), since these frequencies are considered not to add risks to the AIMD functioning. Here we analyze the theoretical issues about the interference between 5G technology and PM/ICD and propose an experimental approach to perform a measurement campaign.


Assuntos
Telefone Celular , Desfibriladores Implantáveis , Marca-Passo Artificial , Humanos , Campos Eletromagnéticos/efeitos adversos , Arritmias Cardíacas/terapia
2.
Radiat Prot Dosimetry ; 172(4): 496-500, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26656081

RESUMO

Time-integrated measurements of indoor radon levels are commonly carried out using solid-state nuclear track detectors (SSNTDs), due to the numerous advantages offered by this radiation detection technique. However, the use of SSNTD also presents some problems that may affect the accuracy of the results. The effect of overlapping tracks often results in the underestimation of the detected track density, which leads to the reduction of the counting efficiency for increasing radon exposure. This article aims to address the effect of overlapping tracks by proposing an alternative calibration technique based on the measurement of the fraction of the detector surface covered by alpha tracks. The method has been tested against a set of Monte Carlo data and then applied to a set of experimental data collected at the radon chamber of the Istituto Nazionale di Metrologia delle Radiazioni Ionizzanti, at the ENEA centre in Casaccia, using CR-39 detectors. It has been proved that the method allows to extend the detectable range of radon exposure far beyond the intrinsic limit imposed by the standard calibration based on the track density.


Assuntos
Poluentes Radioativos do Ar/análise , Polietilenoglicóis/química , Monitoramento de Radiação/instrumentação , Monitoramento de Radiação/métodos , Radônio/análise , Calibragem , Humanos , Método de Monte Carlo
3.
Radiat Prot Dosimetry ; 167(4): 425-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25527181

RESUMO

The aim of this study was to investigate the effect of ageing and fading on PADC detector response, as a function of the storage time and temperature. Several groups of CR-39 detectors provided by Radosys, Ltd. were exposed at the reference radon chamber of the Istituto Nazionale di Metrologia delle Radiazioni Ionizzanti, at the ENEA centre in Casaccia. The results indicate that low-temperature storage inhibits the effect of both ageing and fading. Finally, the overall reduction in CR-39 sensitivity due to the combined ageing/fading effect was estimated. In particular, the sensitivity of the detectors continuously exposed in air at room temperature over 6 and 3 months was reduced, respectively, by 7.5 and 4 %.


Assuntos
Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Polietilenoglicóis/química , Monitoramento de Radiação/instrumentação , Radônio/análise , Calibragem , Monitoramento de Radiação/métodos
4.
Radiat Prot Dosimetry ; 162(4): 625-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24573967

RESUMO

The indoor radon concentration was measured in 16 schools and 6 public departments in the Ardea municipality, using both active and passive detectors. The annual concentration of radon has been determined as the mean of two consecutive 6-month periods of sampling from January 2012 to January 2013. The indoor radon level measured in the monitored buildings ranged from 17 to 918 Bq·m(-3), with a mean value of 154 Bq·m(-3). In addition, the correlation between short-term and long-term measurements was studied. Experimental data demonstrate that the deviation of short-term measurements with respect to polyallyl diglycol carbonate data does not exceed ±40 % in a very extended range of radon concentrations.


Assuntos
Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Radônio/análise , Poluentes Radioativos do Ar/efeitos adversos , Poluição do Ar em Ambientes Fechados/efeitos adversos , Coleta de Dados , Humanos , Logradouros Públicos , Monitoramento de Radiação , Radiometria , Radônio/efeitos adversos , Cidade de Roma , Instituições Acadêmicas
5.
Radiat Prot Dosimetry ; 158(1): 107-10, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23918743

RESUMO

Solid-state nuclear track detectors are commonly used for the detection of indoor radon levels. However, despite numerous advantages, this technique still presents many unsolved problems. An important source of error is represented by the reduction in the detection efficiency due to overlapping tracks, which results in a sensible underestimation of the radon levels. This paper presents a new experimental procedure to address the effect of overlapping tracks by establishing a relationship between the detection efficiency and the number of detected tracks. Experimental data have been collected at the radon chamber of the Istituto Nazionale di Metrologia delle Radiazioni Ionizzanti (INMRI), at the ENEA centre in Casaccia, using CR-39 detectors provided by Radosys Ltd. It has been proved that the method, applied to the experimental settings of this study, gives reliable results up to 7607 kBq h m(-3). Finally, the method has been validated through a Monte Carlo simulation, exploring a wide range of radon exposure.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Polietilenoglicóis/química , Monitoramento de Radiação/métodos , Radiometria/métodos , Radônio/análise , Exposição Ambiental , Humanos , Método de Monte Carlo , Plásticos , Monitoramento de Radiação/instrumentação , Radiometria/instrumentação
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