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13 postsFilters: category: thermal-effects Clear
Electromagnetic Exposure from RF Antennas on Subway Station Attendant: A Thermal Analysis
This paper reports a multiphysics electromagnetic–thermal simulation of radiofrequency (RF) antenna exposure for a subway station attendant, estimating specific absorption rate (SAR) and temperature rise in the trunk and selected organs at 900, 2600, and 3500 MHz. Using a COMSOL-based model with a detailed human anatomy representation, the authors found simulated SAR and temperature increases that they state are well below ICNIRP occupational exposure limits. The study concludes that RF emissions from antennas in the modeled subway environment pose low health risk for female attendants with similar characteristics to the model used, while noting the work is based on simulations rather than measurements.
Effect of fat thickness on subcutaneous temperature field under monopolar radiofrequency
This PubMed-listed study models and experimentally validates how subcutaneous fat thickness affects temperature distribution during monopolar radiofrequency (RF) treatment used for skin tightening and tissue repair. Using finite element analysis (COMSOL) and in vitro pork tissue experiments, the authors report that thicker fat layers reduce achieved intratissue temperatures under the same RF settings. The paper concludes that RF energy parameters may need adjustment based on adipose thickness to reach desired effects while staying within stated epidermal safety limits.
Parametric analysis of electromagnetic wave interactions with layered biological tissues for varying frequency, polarization, and fat thickness
This PubMed-listed study models how RF electromagnetic waves interact with a simplified three-layer tissue structure (skin–fat–muscle) across common ISM bands (433, 915, 2450, 5800 MHz), varying polarization (TE/TM), incidence angle, and fat thickness. Using a custom MATLAB pipeline combining multilayer transmission-line methods, Cole–Cole dielectric parameters, and a steady-state Pennes bioheat solution, the authors estimate reflection, absorption, and resulting temperature rise. The simulations report small temperature increases at lower frequencies (433–915 MHz) and larger superficial heating at 5.8 GHz under the modeled conditions, highlighting how fat thickness and wave parameters modulate dosimetry and thermal outcomes.
Radio Frequency Exposure in Military Contexts: A Narrative Review of Thermal Effects and Safety Considerations
This narrative review focuses on RF exposure in military contexts, emphasizing thermal effects as the established mechanism of harm and discussing safety limits set by bodies such as ICNIRP and IEEE. It reports that whole-body SAR limits (≤4 W/kg) generally prevent dangerous core temperature rises, but localized heating risks may persist for tissues like skin and eyes, especially when thermoregulation is impaired. The review highlights CEM43 as a potentially useful thermal-dose metric but notes complexity for transient exposures and calls for improved models and methods across relevant frequency bands.
Exposure to 5G-NR electromagnetic fields affects larval development of Aedes aegypti mosquito
This animal study exposed Aedes aegypti larvae to 5G-NR RF-EMF at 3.6 GHz for 5 days under two feeding regimes. The study reports delayed development at a lower exposure level mainly in nutritionally weakened larvae, and at a higher exposure level reports developmental changes and reduced adult size attributed to dielectric heating. Mortality and wing length asymmetry were reported as unchanged, and the authors note such high exposure levels are unlikely in natural aquatic settings.
Model Variability in Assessment of Human Exposure to Radiofrequency Fields
This review examines how variability in computational dosimetry models affects assessment of human RF exposure from MHz to terahertz frequencies, focusing on SAR, absorbed power density, and temperature rise. It reports that anatomical scaling and model choices can drive meaningful differences in predicted SAR (including higher values in children/smaller models), while temperature-rise predictions are especially sensitive to thermophysiological parameters and vascular modeling. The authors indicate that computed variability remains within ICNIRP/IEEE safety margins but argue that uncertainties warrant ongoing research and refinement as new technologies (e.g., 6G) emerge.
Thermal and SAR-Based Limits for Human Skin Exposed to Terahertz Radiation
This conference paper uses COMSOL Multiphysics simulations to evaluate thermal and SAR-based exposure limits for modeled human skin exposed to terahertz radiation (0.1–5 THz). The authors report negligible temperature increases at power densities consistent with keeping SAR below 1.6 W/kg, but note that higher power densities can yield minimal heating while producing SAR values above recognized safety thresholds. They conclude that existing sub-THz standards are not directly transferable to the full THz band and call for updated guidelines, especially for prolonged exposure.
Numerical analysis of the thermal effects on adult with brain pacemaker implantation exposed to WIFI antennas
This numerical study modeled RF exposure from WiFi/5G-type antennas near a 3D brain model with implanted brain pacemakers relevant to Parkinson’s disease. SAR and temperature increases were reported to remain below ICNIRP 2020 limits across modeled conditions, with maxima at a 90° antenna-to-brain angle. Despite compliance with SAR/temperature limits, the authors report modeled thermal strain and tissue displacement that could affect postoperative efficacy, leading them to recommend caution and increased distance from phones.
Numerical Analysis of Human Head Exposure to Electromagnetic Radiation Due to 5G Mobile Phones
This conference paper uses numerical simulations to evaluate near-field exposure and thermal effects in a detailed human head model from a realistic 5G mobile phone operating at 26 GHz. The preliminary modeling suggests moderate, localized temperature increases in superficial tissues. The authors emphasize the need for higher-resolution models, refined tissue segmentation, longer exposure durations, and varied phone placements to better characterize potential impacts.
Standards: Exposure Limits for Brief High Intensity Pulses of Radiofrequency Energy Between 6 and 300 GHz
This standards-focused paper evaluates ICNIRP and IEEE (C95.1-2019) exposure limits for brief, high-intensity pulsed RF-EMF between 6 and 300 GHz, particularly when exposures vary within the 6-minute averaging window. Using numerical and analytical modeling with a one-dimensional thermal tissue model, it reports differences in protection against transient skin heating, with IEEE described as more conservative than ICNIRP. The authors propose an adjustment to pulse fluence limits to improve consistency of protection and note that nonthermal and thermoacoustic effects were not analyzed.
Characterization of the Core Temperature Response of Free-Moving Rats to 1.95 GHz Electromagnetic Fields
This animal study measured core body temperature in free-moving male and female Sprague Dawley rats during and after 3-hour exposure to 1.95 GHz RF-EMF at multiple whole-body average SAR levels. A measurable thermal response was reported at 4 W/kg, while lower SAR conditions showed smaller or no significant temperature increases. The authors note that temperature dropped quickly after exposure ended, implying post-exposure measurements may underestimate peak heating.
Assessment of RF EMF Exposure to Car Driver from Monopole Array Antennas in V2V Communications Considering Thermal Characteristics
This modeling study assessed RF-EMF exposure from a 5.9 GHz V2V monopole array antenna integrated into a car roof shark-fin antenna. Using COMSOL simulations with an adult male body model inside a vehicle, the authors estimated localized and whole-body SAR and associated core temperature rise over a 30 min averaging period. Reported SAR and temperature rise values were below ICNIRP occupational thermal-based restrictions, leading the authors to conclude the exposure does not pose a threat under the studied conditions.
Single exposure to near-threshold 5G millimeter wave modifies restraint stress responses in rats
In a rat experiment (n=59), a single 40-minute whole-body 28 GHz exposure at near-threshold WBA-SAR levels was evaluated under normal and heat conditions with restraint. After accounting for sham-related restraint stress, exposure was associated with increased serum-free corticosterone 1–3 days later, especially when rectal temperature rose by >1°C. Urinary catecholamines suggested an immediate inhibitory effect on stress response (notably noradrenaline), with heat amplifying effects and linking noradrenaline to tail surface temperature.