Near field energy densities of hand-held transceivers

Calculations are presented that indicate with reasonable accuracy that hand-held transmitter-receiver units used by amateur radio operators, although excluded from ANSI Standard C95.1-1982 protection guidelines, may be a radiation hazard. The transmitters generate between 1 and 5 W of radiofrequency power and operate at the 2-m, 75-cm, and other UHF bands. These units use short spiral (rubber ducky) antennas that are held near the face during transmissions. Although no calculations or measurements give unequivocal values for the electromagnetic energy in the near-field, energy densities in the induction fields (within the head of the user) may be an order of magnitude greater than ANSI protection guidelines. This analysis indicates that it is not prudent to hold the transceiver four or five inches from the face, as is normally done. Certainly it should not be held against the cheek. It is recommended instead that a hand-held transceiver be held at arm's length when transmitting.<>