Electromagnetic Interference Measurements of Fluorescent Lamps Operated with Solid-State Ballasts

Solid-state ballasts were placed in fluorescent lamps in various areas of a hospital to determine if these high-frequency systems would adversely affect any hospital operations. The general areas tested included a lobby and an office space. Potentially sensitive areas containing hospital diagnostic and monitoring equipment, including a computerized axial tomography (CAT) scanning room, an electroencephalograph (EEG) examination room, and a coronary ward were also tested. The measurement techniques are described and the results discussed with respect to the existing radio-frequency interference (RFI) environment and with respect to electromagnetic interference (EMI) radiated and conducted limits specified by the Federal Communications Commission (FCC) and the Federal Drug Administration (FDA).