The exposure system consisted of three groups of Helmholtz coils, two power regulators and a set of CO2 incubators. The magnetic fields were generated from line current . Cell culture dishes were placed coaxially with the centerline in the central area of the coils. Sham exposed cells as control were placed in an identical incubator without magnetic fields.
The AC background field was 1-2 µT and the static magnetic field was 18.5 µT, with a 14.1 µT horizontal and a 12.0 µT vertical component.