Evaluation of the efficacy of commercial devices used for protection against electromagnetic fields emitted by cellular phones

Rosanna Pinto, Alessandro Polichetti, Giorgio A. Lovisolo

Research output: Contribution to journalArticle


This study aims to experimentally assess the protective efficacy against electromagnetic radiation emitted by cellular phones of some commercially available devices of different shapes and sizes. Comparative measurements have been performed of electromagnetic power absorbed per unit of mass (SAR, Specific Absorption Rate, W/kg) and of the diagram of far-field radiation to assess eventual changes in the quality of the signal emitted by cellular phones. The results show that even if the devices are used according to the manufacturer's instructions they are ineffective. However, in certain conditions, some of them seem to be able to modify the structure of the electromagnetic field generated by the phone antenna as suggested by variations (increase or decrease) in the SAR and by the results of the radiometric measurements carried out applying the devices in different positions on the phone. The behaviour of another kind of devices has been examined, widely used with cellular phones, designed to have free hands through the use of earphones, and also used to reduce exposure of the head to electromagnetic fields. In response to the doubts raised by a British consumer association, a series of comparative measurements have been made under specific conditions to verify the actual electromagnetic energy dissipated in the head through the earphone or directly by the telephone itself. About twenty devices have been analysed with the telephones of three producers. The analysis has confirmed the significant reduction of the electromagnetic energy dissipated in the head by the use of hands free kits.
Original languageEnglish
Pages (from-to)19 - 26
Number of pages8
JournalPhysica Medica
Issue number1
Publication statusPublished - Jan 2004
Externally publishedYes


All Science Journal Classification (ASJC) codes

  • Biophysics
  • Physics and Astronomy(all)

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