[Standardization of electromagnetic fields of 3-30 MHz with reference to the time factor].

In chronic experiments (4 months) in rabbits, rats, and mice biological effects were investigated from 7 exposure regimen of electromagnetic fields with a frequency of 24 MHz at field strengths of the electric field component of 125, 250, 500, and 1,000 V/m, respectively, and an exposure time of 0.25, 1, and 4 hrs. respectively. The effects on the CNS, the immune and hormone systems, the peripheral blood and on the spermato and embryo genesis were estimated. The results delivered the basis for the introduction of an index. In point of time different limit values are to be determined according to the energetic load. A concrete value for the energetic load 7,200 (V/m)2.h is proposed as maximum allowable field strength of the electric component 300 V/m.