A Characterization of Occupational Static Magnetic Field Exposures at a Diaphragm-Cell and a Mercury-Cell Chlor-Alkali Facility

Abstract

Static magnetic field levels from direct current were studied in two chlor-alkali facilities, one a diaphragm-cell and one a mercury-cell technology facility. At the diaphragm-cell facility, static magnetic fields ranged from 1.0 to 173.2 Gauss (G), with an average of 82.3 G. At the mercury-cell facility, levels ranged from 4.1 to 182.9 G, with an average of 46.8 G. At the diaphragm-cell facility, field strengths were highest at the mid-height (3.5 feet) level. There was no difference in field strength by height at the mercury-cell facility. In both facilities, field strengths were higher at sampling locations closer to the electrical buss bar. Static magnetic field strengths at the property lines were comparable to expected background levels (below detection to 2.5 G). Measurements near the cell building (25–45 feet away) were slightly higher and ranged from 0.4 to 15.0 G. All measurements inside and outside the cell buildings were below the American Conference of Governmental Industrial Hygienists ceiling guideline (600 G); however, levels inside and near the cell buildings were greater than the guideline of 10 G for persons having implanted cardiac pacemakers. Given the increased attention to the potential health effects of electromagnetic fields in general, it is important to characterize carefully and limit occupational exposures to static magnetic fields.