Human exposure to electric and magnetic fields from RF sealers and dielectric heaters--a COMAR technical information statement.

Radio frequency (RF) sealers and dielectric heaters, operating between 3 and 100 MHz, are used for a variety of industrial applications. There is concern about the safety of such devices because measurements during operation often show leakage of electric and magnetic fields, as well as induced currents in the body, that exceed RF exposure guidelines. Both the leakage of fields and the absorption of RF energy by an operator can be reduced by shielding, proper grounding of the sealers, isolation of the operator from ground, and increasing the distance between the sealer and the operator. Several national and international standards now include limits on body-to-ground and contact currents for humans. Based on present knowledge of the biological effects of RF fields and the reported exposures from such devices, COMAR recommends that the leakage field strengths from RF sealers and dielectric heaters, as well as body-to-ground and contact currents, be monitored and exposure to workers be limited so as to meet the recommended RF exposure guidelines.