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New measurement methods and equipment for correct 5G New Radio (NR) electromagnetic field (EMF) in-situ exposure assessment of instantaneous time-averaged exposure (Eavg) and maximum extrapolated field exposure (Emax) are proposed. The different options are investigated with in-situ measurements around 5G NR base stations (FR1) in different countries. The maximum electric field values satisfy the ICNIRP 2020 limit (maximum 7.7%). The difference between Emax and Eavg is

This paper describes radiofrequency (RF) electromagnetic field (EMF) measurements in the vicinity of single and banks of advanced metering infrastructure (AMI) smart meters. The measurements were performed in a meter testing and distribution facility as well as in-situ at five urban locations. The measurements consisted of gauging the RF environment at the place of assessment, evaluating the worst-case electric-field levels at various positions around the assessed AMI meter configuration (spatial assessment), which ranged from a single meter to a bank of 81 m, and calculating the duty cycle of the system, i.e. the fraction of time that the AMI meters were actually transmitting (12-h temporal assessment). Both in-situ and in the meter facility, the maximum field levels at 0.3 m from the meter configurations were 10-13 V/m for a single meter and 18-38 V/m for meter banks with 20-81 m. Furthermore, 6-min average duty cycles of 0.01% (1 m) up to 13% (81-m bank) were observed. Next, two general statistical models (one for a single meter and one for a meter bank) were constructed to predict the electric-field strength as a function of distance to any configuration of the assessed AMI meters. For all scenarios, the measured exposure levels (at a minimum distance of 0.3 m) were well below the maximum permissible exposure limits issued by the International Commission on Non-Ionizing Radiation Protection (ICNIRP), the U.S. Federal Communications Commission (FCC), and the Institute of Electrical and Electronics Engineers (IEEE). Indeed, the worst-case time-average exposure level at a distance of 0.3 m from an AMI installation was 5.39% of the FCC/IEEE and 9.43% of the ICNIRP reference levels.

A multi-band body-worn distributed exposure meter (BWDM) is designed and calibrated for diffuse fields in a reverberation chamber (RC) for personal exposure assessment in indoor environments. The BWDM uses 22 nodes distributed over the torso and measures the incident power density ( $S_{\mathrm{ inc}}$ ) on body for 11 telecommunication bands in the frequency range of 790–5513 MHz. In order to calibrate the measurement device in diffuse fields, a protocol is proposed for on-body calibration of the BWDM. This protocol is applicable to wearable personal exposure meters in general. The BWDM and the proposed calibration protocol are validated in five indoor locations and five frequency bands (the downlink bands at 800, 900, 1800, and 2100 MHz as well as Wi-Fi 2 GHz) using a tri-axial broadband antenna and a spectrum analyzer (SA). The calibration shows that the BWDM has a relatively low measurement uncertainty with a 68% confidence interval on its antenna apertures, in the range 3.4–5.5 dB. A maximum difference of 0.9 dB is obtained for the total exposure in the test areas between the measurements of the BWDM and SA, which is an excellent agreement.

The advent of the Internet of things comes with a huge increase in wirelessly communicating devices in our environment. For example, smart energy-consumption meters are being widely deployed in residences from which they communicate their state using radiofrequency networks. Accurate characterization of the radiofrequency emissions from emerging residential wireless solutions is important to inform the public about the potential impact on their exposure to radiofrequency electromagnetic fields. A new measurement procedure to determine the exposure from residential radiofrequency devices is proposed by assessing the peak emitted fields at various distances and the proportion of time they transmit (duty cycle). Radiofrequency emissions from 55 residential devices were measured in 10 residences (Belgium and France) and compared to environmental levels, emissions from 41 mobile phones, and international standards. Overall, residential levels of radiofrequency electromagnetic field exposure are low. In addition to the continuous environmental exposure, wireless access points (due to frequent use) and especially mobile phones and other personal communication devices (due to their use close to the body) continue to represent the bulk of the radiofrequency electromagnetic field exposure in the smart home. However, some residential devices can significantly increase the exposure if their duty cycles are high enough (>10%), especially when held or used close to the body. Individual smart meters, on the other hand, will contribute only little in general, despite emissions of up to 20 V m(-1) at 50 cm, due to their low duty cycles (maximum 1%) and locations.

This paper studies the effect of antenna polarization on measurement uncertainty of a multi-band body-worn distributed exposure meter (BWDM). The BWDM is a device for assessing electromagnetic fields in real environments accurately. The BWDM consists of 8 nodes and is calibrated on the body for simultaneous measurement of the incident power density in four frequency bands. Each node contains an antenna that can have two potential antenna polarizations.The BWDM is calibrated on four human subjects in an anechoic chamber to determine its measurement uncertainty in terms of 68% confidence interval (CI68) of the on-body antenna aperture. The results show that using a fixed polarization of the antennas on body can lead to a different CI68 up to maximum 4.9 dB when worn by another person which is still 9.6 dB lower than the measurement uncertainty of commercial exposure meters.

This paper describes the assessment of radiofrequency (RF) electromagnetic field (EMF) exposure from fifth generation (5G) new radio (NR) base stations in a commercial NR network in Bern, Switzerland. During the measurement campaign, four base station sites were investigated and the exposure induced by the NR massive multiple-input-multiple-output (MaMIMO) antennas was assessed at 22 positions, at distances from the base station between 30 m and 410 m. The NR base stations operated at 3.6 GHz and used codebook-based beamforming. While the actual field levels without inducing downlink traffic were very low (&lt, 0.05 V/m) due to a low traffic load and low antenna input powers of up to 8 W, setting up a maximum downlink traffic stream towards user equipment resulted in a time-averaged exposure level of up to 0.4 V/m, whereas the maximum extrapolated exposure level reached 0.6 V/m. Extrapolated to an antenna input power of 200 W, values of 4.3 V/m and 4.9 V/m, respectively, were obtained, which amount to 0.5–0.6% of the reference level recommended by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). In Bern, it was found that the impact of the NR network on the total environmental RF exposure was very limited, with maximum downlink, it contributed 2% on average. Finally, it was also concluded that extrapolation to the maximum exposure level can be done without prior knowledge of the radiation patterns, directly based on the measurement of the Physical Downlink Shared Channel (PDSCH) resource elements.

For the first time, a dual band wearable personal distributed exposure meter (DPDE) is designed. The DPDE is calibrated on-body in a reverberation chamber. The meter consists of four nodes including textile antennas operating at 2443 MHz (WiFi 2 GHz) and 2595 MHz (LTE 2600 MHz). The location of the nodes are optimized based on the calibration in a reverberation chamber. The results show that the DPDE has a high antenna-body isolation and thus its performance is less affected by presence of the human body. The measurement uncertainty of the designed DPDE is maximum 4.5 dB in terms of 68% confidence interval of its response. The results are validated in a real office environment for WiFi 2 GHz. The DPDE has a detection limit of $3\ \mu W.m^{-2}$ in diffuse fields.

A multi-band Body-Worn Distributed exposure Meter (BWDM) calibrated for simultaneous measurement of the incident power density in 11 telecommunication frequency bands, is proposed. The BDWM consists of 22 textile antennas integrated in a garment and is calibrated on six human subjects in an anechoic chamber to assess its measurement uncertainty in terms of 68% confidence interval of the on-body antenna aperture. It is shown that by using multiple antennas in each frequency band, the uncertainty of the BWDM is 22 dB improved with respect to single nodes on the front and back of the torso and variations are decreased to maximum 8.8 dB. Moreover, deploying single antennas for different body morphologies results in a variation up to 9.3 dB, which is reduced to 3.6 dB using multiple antennas for six subjects with various body mass index values. The designed BWDM, has an improved uncertainty of up to 9.6 dB in comparison to commercially available personal exposure meters calibrated on body. As an application, an average incident power density in the range of 26.7-90.8 muW.m - 2 is measured in Ghent, Belgium. The measurements show that commercial personal exposure meters underestimate the actual exposure by a factor of up to 20.6.

Rising concern about the potential harmfulness of human radio-frequency exposure causes scientists to be highly interested in measuring these exposure levels. The set of measured signal levels on a map of locations is then used for epidemiological research, looking for correlation to the incidence of certain illnesses. Currently available hand-held exposimeters have the disadvantage that the measured signal levels are often significantly different from the exposure to which the human body is actually subjected. Therefore, a personal distributed exposimeter was developed and documented in this paper. Multiple on-body antennas are employed in order to measure the electromagnetic field strengths directly on the body. In this design, 11 commonly used frequency bands are measured, with front and back textile antennas for each of those bands. These 22 antennas are implemented in substrate-integrated-waveguide technology, thereby combining a compact size with a large bandwidth. The measurement system operates autonomously, through measurement, control and data-logging circuitry directly integrated onto the antennas. The textile-antenna based nodes are unobtrusively integrated into a garment, resulting in maximum comfort for the user. A measurement campaign using the system is currently underway in a number of European countries, yielding a large amount of valuable and unique data for epidemiological analyses.

For the first time, a wearable personal distributed exposimeter (WPDE) is designed and calibrated for the Long-Term Evolution (LTE) 800 and 2600 MHz downlink bands. The proposed WPDE has a 68% confidence interval of 4.8–5.6 dB for different number of antennas and polarizations. Measurements of the WPDE are compared and validated with a commercial exposimeter in a real environment.

Human exposure to electric and magnetic fields has been amply investigated in the extremely-low frequency (ELF) and radiofrequency (RF) ranges. However, research on typical emissions in the intermediate-frequency (IF) range remains limited. In this study, an extensive measurement survey was performed on the levels of electric and magnetic fields at intermediate frequencies typically emitted by a wide range of household appliances. The emissions contained either harmonic signals, with fundamental frequencies between 6 kHz and 100 kHz, or much more capricious spectra, dominated by 50 Hz harmonics emanating far in the IF domain. Use of appliances at close distance (20 cm) of certain appliances may result in a relatively high exposure, but no appliance's IF emissions exceeded the ICNIRP2010 exposure summation rule (maximum electric- and magnetic-field exposure quotients were respectively 1.00, for a compact fluorescent lamp, and 0.13, for an induction cooker).

In situ exposure of electric fields of 11 microwave ovens is assessed in an occupational environment and in an office. Measurements as a function of distance without load and with a load of 275 ml of tap water were performed at distances of < 1 m. The maximal measured field was 55.2 V m(-1) at 5 cm from the oven (without load), which is 2.5 and 1.1 times below the International Commission on Non-Ionizing Radiation Protection reference level for occupational exposure and general public exposure, respectively. For exposure at distances of > 1 m, a model of the electric field in a realistic environment is proposed. In an office scenario, switching on a microwave oven increases the median field strength from 91 to 145 mV m(-1) (+91 %) in a traditional Wireless Local Area Network (WLAN) deployment and from 44 to 92 mV m(-1) (+109 %) in an exposure-optimised WLAN deployment.

In this study, in situ exposure assessment of both electric and magnetic fields of different intermediate frequency (IF) sources is investigated. The authors investigated smart boards and touchscreens, energy-saving bulbs, fluorescent lamps, a portable hearing unit and an electrosurgical unit (ESU). For most of these sources, the electric field is the dominating quantity. International Commission on Non-Ionizing Radiation Protection reference levels are exceeded for touchscreens (44 kHz: up to 155.7 V m(-1) at 5 cm), energy-saving bulbs (38-52 kHz: up to 117.3 V m(-1)), fluorescent lamps (52 kHz: up to 471 V m(-1) at 5 cm) and ESUs (up to 920 kHz: 792 V m(-1) at 0.5 cm). Magnetic field strengths up to 1.8 and 10.5 A m(-1) were measured close to the ESU and portable hearing unit (69 V m(-1)), respectively. Large differences of measured field values exist among the various operating modes of the IF equipment. Compliance distances for general public range from 15.3 cm (touchscreen) to 25 cm (fluorescent lamps).