Can this be safe?

Ricardo is demonstrating the use of his transceiver for body-coupled communication by strapping it to his head. Irfan, not shown in the picture, is standing by with another transceiver in his hand.

When shaking hands, effectively bridging Portugal and Pakistan :), they also demonstrate that a communication link is established.

Ricardo Matias in action (and sorry for the somewhat shaky photo).

The power levels are orders of magnitude less than those of mobile phones and operating frequencies are selected to be well above the "biological frequencies" of the human body. The body has a frequency profile up to some kHz.