EVALUATING EXTREMELY LOW FREQUENCY MAGNETIC FIELDS IN THE REAR SEATS OF THE ELECTRIC VEHICLES

Electromagnetic exposure levels of electric vehicle drive motors to cochlear implanted passenger

In order to evaluate the effects of electromagnetic radiation generated by the dual-drive motors of an electric vehicle on special passengers with cochlear implanted, this study considers a cochlear implanted passenger as the research object, takes the drive motors in electric vehicle as the exposure source. A calculation model including the vehicle body, brain tissue, skull, eyes, human body, and cochlear implant is built, and the finite element method is used to calculate the induced electric field ([Formula: see text]), specific absorption rate (SAR), and temperature changes in different tissues and organs of the passenger's body. The results show that the maximum value of [Formula: see text] on the human body surface is 60.8 mV/m at the ankle. The [Formula: see text] around the cochlear implant inside the human head is also high, with a maximum value of 57.1 mV/m. The maximum SAR of the human body is [Formula: see text], which also appears near the cochlear implant. Besides, the maximum temperature rise of the human body, brain tissue, and cochlear implant is 0.10 °C, 0.28 °C, and 0.0076 °C, respectively. Calculation shows that the [Formula: see text] and SAR of the human body and different tissues are much lower than the safety limit specified in the guidelines of the International Commission on Non-Ionizing Radiation Protection (ICNIRP), and the temperature rise does not reach the thermal damage threshold in the guidelines. The electric field around the electrode tip and the surface of the cochlear implant, the temperature rise of the cochlear implant also meet the requirements of the ICNIRP and the International Organization for Standardization's 14708-7 medical device standard. The results could enrich the study on the electromagnetic environment of electric vehicles and provide references for the design and improvement of cochlear implants and electromagnetic exposure protection for vehicles.

Electromagnetic exposure level of pure electric vehicle inverter to human body in different seating positions

The market share of pure electric vehicle (PEV) as a green transportation steadily increases as the global demand for renewable energy sources and environmentally friendly mobility continues to increase. However, during PEV operation, the inverter system, as the key power conversion device, generates strong electromagnetic field in the local space. Long-term exposure to such electromagnetic environments may have potential effects on human body. In this study, the electromagnetic environment model of the PEV body, human body and simplified inverter is established. The finite element software, COMSOL Multiphysics, is used to calculate and analyse the variations in the induction field in different tissues of the driver and rear passenger, caused by the electromagnetic field generated by the inverter system operating at maximum power. The electromagnetic exposure level of the driver and rear passenger is assessed. Results show significant differences in the electromagnetic exposure levels of different seating positions in the vehicles. The electromagnetic exposure level in the driver's body is higher than that of the rear passenger, but it does not exceed the exposure limits defined by the International Commission for Non-ionizing Radiation Protection. This finding effectively complements the study on evaluating the safety of the electromagnetic environment of PEV and improves public awareness.

Extremely low frequency magnetic fields (ELF-MF) in Switzerland: From exposure monitoring to daily exposure scenarios

Exposure to extremely low frequency magnetic fields (ELF-MF) is ubiquitous in our daily environment. This study aims to provide a comprehensive overview of the ambient ELF-MF exposure in Switzerland and presents a novel environmental exposure matrix for exposure assessment and risk communication. Magnetic flux density levels (µT) were measured using a portable exposimeter carried in a backpack for the main ELF sources: railway power (16.7 Hz), domestic power (50 Hz), and tram ripple current (300 Hz). We collected ELF-MF levels between 2022 and 2024 in various environments representative of the Swiss population: 300 outdoor areas (e.g. city centres, residential areas), 245 public spaces (e.g. train stations, schools), 348 transport journeys (e.g. train, cars), and in 59 homes (e.g. bedrooms, living rooms). Over all environments, the highest ELF-MF exposure levels were measured in train stations (median: 0.48 µT), trains (median: 0.40 µT), and in living rooms near (<200 m) highest voltage lines of 220 kV and 380 kV (median: 0.37 µT). ELF-MF median levels measured two years apart showed high Pearson correlation coefficients in the same 150 outdoor areas (r = 0.88) and 86 public spaces (r = 0.87), without any significant changes. All measurements are well below the Swiss ambient regulatory limit based on the ICNIRP 1998 guidelines (median: 0.2 %). Finally, we derived an environmental exposure matrix and modelled 27 daily time-weighted average ELF-MF exposure scenarios by combining typical time spent at home, work and transport environments. People who do not live near highest voltage lines or work in highly exposed environments are typically exposed to less than 0.3 µT on average, while those who do are likely to exceed this level. This novel environmental exposure matrix is a useful tool for public communication and agent-based exposure modelling for future epidemiological research.

LOW FREQUENCY MAGNETIC FIELDS INSIDE CARS

Magnetic fields were compared inside passenger seats of electric, petrol and hybrid cars. While driving about 5 km in an urban environment, values were recorded and compared between car types. The magnetic flux densities of the cars were less than 2.6 μT. The magnitudes of the magnetic fields of petrol cars and hybrid cars were about the same and slightly lower for electric cars. Based on our measurements, values were less than 3% of the guidelines given for the general population or people using pacemakers.

Long-Term Monitoring of Extremely Low Frequency Magnetic Fields in Electric Vehicles

Extremely low frequency (ELF) magnetic field (MF) exposure in electric vehicles (EVs) has raised public concern for human health. There have been many studies evaluating magnetic field values in these vehicles. However, there has been no report on the temporal variation of the magnetic field in the cabin. This is the first study on the long-term monitoring of actual MFs in EVs. In the study, we measured the magnetic flux density (B) in three shared vehicles over a period of two years. The measurements were performed at the front and rear seats during acceleration and constant-speed driving modes. We found that the B amplitudes and the spectral components could be modified by replacing the components and the hubs, while regular checks or maintenance did not influence the B values in the vehicle. This observation highlights the necessity of regularly monitoring ELF MF in EVs, especially after major repairs or accidents, to protect car users from potentially excessive ELF MF exposure. These results should be considered in updates of the measurement standards. The ELF MF effect should also be taken into consideration in relevant epidemiological studies.