Evaluation of SAR and Temperature Rise in Human Hand Due to Contact Current From 100 kHz to 100 MHz
International guidelines/standards for the protection of humans from radiofrequency exposure have set a limit by assuming the lowest threshold for a classical heating effect, among other effects. However, no computational study has been reported that evaluates temperature rise due to contact current...
| Main Authors: | , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IEEE
2020-01-01
|
| Series: | IEEE Access |
| Subjects: | |
| Online Access: | https://ieeexplore.ieee.org/document/9247983/ |
| _version_ | 1819173316604198912 |
|---|---|
| author | Taiki Murakawa Yinliang Diao Essam A. Rashed Sachiko Kodera Yoshihiro Tanaka Yoshitsugu Kamimura Shin Kitamura Shintaro Uehara Yohei Otaka Akimasa Hirata |
| author_facet | Taiki Murakawa Yinliang Diao Essam A. Rashed Sachiko Kodera Yoshihiro Tanaka Yoshitsugu Kamimura Shin Kitamura Shintaro Uehara Yohei Otaka Akimasa Hirata |
| author_sort | Taiki Murakawa |
| collection | DOAJ |
| description | International guidelines/standards for the protection of humans from radiofrequency exposure have set a limit by assuming the lowest threshold for a classical heating effect, among other effects. However, no computational study has been reported that evaluates temperature rise due to contact currents. This paper presents the computational dosimetry of a specific absorption rate (SAR) and temperature rise due to touch contact currents in the frequency range 100 kHz to 100 MHz using a detailed numerical model of a human hand. Tissue dielectric properties obtained from a conventional 4-Cole-Cole dispersion model have often been considered in dosimetry studies. However, a comparison of the computed electrical impedance with experimental results suggests that the conductivity of the subcutaneous fat in the finger should be higher than the 4-Cole-Cole values-potentially attributable to collagen fibers. We then proposed a set of tissue dielectric conductivities estimated from recent measurement results of conductivities for the epidermis, dermis, and subcutaneous tissue. Consequently, the computed electrical impedances exhibited good agreement with the measured ones. In addition, the SAR and temperature rise obtained using the proposed tissue conductivities were lower than those obtained using 4-Cole-Cole values. Therefore, the SAR and temperature rise obtained based on the 4-Cole-Cole dispersion model may be overstated. We also observed that the steady-state maximum temperature rise due to the contact current at the guidance/limit level was equivalent to 2.5 °C, which is the maximum permissible temperature rise (5 °C) divided by a reduction factor of 2. |
| first_indexed | 2024-12-22T20:21:09Z |
| format | Article |
| id | doaj.art-046500de761f42f9b83d4a709c4e172d |
| institution | Directory Open Access Journal |
| issn | 2169-3536 |
| language | English |
| last_indexed | 2024-12-22T20:21:09Z |
| publishDate | 2020-01-01 |
| publisher | IEEE |
| record_format | Article |
| series | IEEE Access |
| spelling | doaj.art-046500de761f42f9b83d4a709c4e172d2022-12-21T18:13:50ZengIEEEIEEE Access2169-35362020-01-01820099520100410.1109/ACCESS.2020.30358159247983Evaluation of SAR and Temperature Rise in Human Hand Due to Contact Current From 100 kHz to 100 MHzTaiki Murakawa0https://orcid.org/0000-0001-9068-8950Yinliang Diao1https://orcid.org/0000-0002-6492-4515Essam A. Rashed2https://orcid.org/0000-0001-6571-9807Sachiko Kodera3https://orcid.org/0000-0001-6595-0742Yoshihiro Tanaka4https://orcid.org/0000-0001-7917-1379Yoshitsugu Kamimura5https://orcid.org/0000-0003-3939-3895Shin Kitamura6https://orcid.org/0000-0002-4442-0854Shintaro Uehara7https://orcid.org/0000-0002-6255-1815Yohei Otaka8Akimasa Hirata9https://orcid.org/0000-0001-8336-1140Department of Electrical and Mechanical Engineering, Nagoya Institute of Technology, Nagoya, JapanDepartment of Electrical and Mechanical Engineering, Nagoya Institute of Technology, Nagoya, JapanDepartment of Electrical and Mechanical Engineering, Nagoya Institute of Technology, Nagoya, JapanDepartment of Electrical and Mechanical Engineering, Nagoya Institute of Technology, Nagoya, JapanDepartment of Electrical and Mechanical Engineering, Nagoya Institute of Technology, Nagoya, JapanDepartment of Information Science, Utsunomiya University, Utsunomiya, JapanFaculty of Rehabilitation, Fujita Health University, Toyoake, JapanFaculty of Rehabilitation, Fujita Health University, Toyoake, JapanDepartment of Rehabilitation Medicine I, Fujita Health University, Toyoake, JapanDepartment of Electrical and Mechanical Engineering, Nagoya Institute of Technology, Nagoya, JapanInternational guidelines/standards for the protection of humans from radiofrequency exposure have set a limit by assuming the lowest threshold for a classical heating effect, among other effects. However, no computational study has been reported that evaluates temperature rise due to contact currents. This paper presents the computational dosimetry of a specific absorption rate (SAR) and temperature rise due to touch contact currents in the frequency range 100 kHz to 100 MHz using a detailed numerical model of a human hand. Tissue dielectric properties obtained from a conventional 4-Cole-Cole dispersion model have often been considered in dosimetry studies. However, a comparison of the computed electrical impedance with experimental results suggests that the conductivity of the subcutaneous fat in the finger should be higher than the 4-Cole-Cole values-potentially attributable to collagen fibers. We then proposed a set of tissue dielectric conductivities estimated from recent measurement results of conductivities for the epidermis, dermis, and subcutaneous tissue. Consequently, the computed electrical impedances exhibited good agreement with the measured ones. In addition, the SAR and temperature rise obtained using the proposed tissue conductivities were lower than those obtained using 4-Cole-Cole values. Therefore, the SAR and temperature rise obtained based on the 4-Cole-Cole dispersion model may be overstated. We also observed that the steady-state maximum temperature rise due to the contact current at the guidance/limit level was equivalent to 2.5 °C, which is the maximum permissible temperature rise (5 °C) divided by a reduction factor of 2.https://ieeexplore.ieee.org/document/9247983/Contact currenthuman safetydosimetry |
| spellingShingle | Taiki Murakawa Yinliang Diao Essam A. Rashed Sachiko Kodera Yoshihiro Tanaka Yoshitsugu Kamimura Shin Kitamura Shintaro Uehara Yohei Otaka Akimasa Hirata Evaluation of SAR and Temperature Rise in Human Hand Due to Contact Current From 100 kHz to 100 MHz IEEE Access Contact current human safety dosimetry |
| title | Evaluation of SAR and Temperature Rise in Human Hand Due to Contact Current From 100 kHz to 100 MHz |
| title_full | Evaluation of SAR and Temperature Rise in Human Hand Due to Contact Current From 100 kHz to 100 MHz |
| title_fullStr | Evaluation of SAR and Temperature Rise in Human Hand Due to Contact Current From 100 kHz to 100 MHz |
| title_full_unstemmed | Evaluation of SAR and Temperature Rise in Human Hand Due to Contact Current From 100 kHz to 100 MHz |
| title_short | Evaluation of SAR and Temperature Rise in Human Hand Due to Contact Current From 100 kHz to 100 MHz |
| title_sort | evaluation of sar and temperature rise in human hand due to contact current from 100 khz to 100 mhz |
| topic | Contact current human safety dosimetry |
| url | https://ieeexplore.ieee.org/document/9247983/ |
| work_keys_str_mv | AT taikimurakawa evaluationofsarandtemperatureriseinhumanhandduetocontactcurrentfrom100khzto100mhz AT yinliangdiao evaluationofsarandtemperatureriseinhumanhandduetocontactcurrentfrom100khzto100mhz AT essamarashed evaluationofsarandtemperatureriseinhumanhandduetocontactcurrentfrom100khzto100mhz AT sachikokodera evaluationofsarandtemperatureriseinhumanhandduetocontactcurrentfrom100khzto100mhz AT yoshihirotanaka evaluationofsarandtemperatureriseinhumanhandduetocontactcurrentfrom100khzto100mhz AT yoshitsugukamimura evaluationofsarandtemperatureriseinhumanhandduetocontactcurrentfrom100khzto100mhz AT shinkitamura evaluationofsarandtemperatureriseinhumanhandduetocontactcurrentfrom100khzto100mhz AT shintarouehara evaluationofsarandtemperatureriseinhumanhandduetocontactcurrentfrom100khzto100mhz AT yoheiotaka evaluationofsarandtemperatureriseinhumanhandduetocontactcurrentfrom100khzto100mhz AT akimasahirata evaluationofsarandtemperatureriseinhumanhandduetocontactcurrentfrom100khzto100mhz |