50 Hz–21.3 kHz
Exposure duration: continuous for 8 h/day (worst case scenerio)
The study did not confirm any substantial suppressive effect of low frequency electromagnetic fields on the immune system of the exposed subjects. A decrease in radical production (oxidative burst) of monocytes in the group working at induction heaters seems to be compensated by an increased number of active cells. The only parameter deviating from control values was a high number of natural killer cells (found in some subjects at induction heaters).