A phone positioning system (headband, adjustable arm, and phone holder) made of non-metallic plastic materials held the phone on the subject's dominant-hand side so that its longitudinal axis followed an imaginary line from the entrance to the ear canal to the corner of the mouth, in accordance with the "touch position" of CENELEC standard EN 50361 .
The mobile phone was controlled via cable by a PC. The sham or genuine exposure was realized using a 50 Ω resistive load or an open-circuit dummy load connected to the remote antenna connector of the phone. Each subject participated in two sessions with real or sham exposure in double-blind random order performed on separate days at least 24 h apart. Each session lasted 26 min: 13 min in supine rest condition followed by 13 min in stand condition.
Measurements of the SAR in the head were made in standard brain tissue equivalent liquid in a phantom using a 3-D step motor robot system, internal E-field probe, and a non-metallic phone-positioning system holding the phone in the "touch position" according to CENELEC standard EN 50361 .