Occupational Exposure Assessment on an FM Mast: Electric Field and SAR Values

• Autorzy: Valic B. , Kos B. , Gajsek P.
• Języki publikacji: EN

Abstrakty

EN

Electric field strengths normally exceed the reference levels for occupational exposure in close vicinity to large frequency modulation (FM) transmitters. Thus, a detailed investigation on compliance with basic restrictions is needed before any administrative protection measures are applied. We prepared a detailed numerical model of a 20-kW FM transmitter on a 32-m mast. An electrically isolated anatomical human model was placed in 3 different positions inside the mast in the region where the values of the electric field were highest. The electric field strengths in this region were up to 700 V/m. The highest calculated whole-body specific absorption rate (SAR) was 0.48 W/kg, whereas the maximum 10-g average SAR in the head and trunk was 1.66 W/kg. The results show that the reference levels in the FM frequency range are very conservative for near field exposure. SAR values are not exceeded even for fields 10 times stronger than the reference levels.

Słowa kluczowe

EN

occupational exposure; exposure assessment; measurements; numerical calculation; SAR; FM; radio tower; FDTD

• Wydawca: Taylor & Francis
• Czasopismo: International Journal of Occupational Safety and Ergonomics
• Rocznik: 2012
• Tom: Vol. 18, No. 2
• Strony: 149--159
• Opis fizyczny: Bibliogr. 15 poz., rys., tab., wykr.

Twórcy

autor

Valic B.

• Institute of Non-Ionizing Radiation, Ljubljana, Slovenia

autor

Kos B.

• Faculty of Electrical Engineering, University of Ljubljana, Slovenia

autor

Gajsek P.

• Institute of Non-Ionizing Radiation, Ljubljana, Slovenia

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