Abstract

RIVM performed pilot measurements of the magnetic field in the neighbourhood of transformer houses, underground cables and household appliances. The measurements were made at the request of the Municipal Public Health Services (GGD) and should provide the GGD with background information for answering questions from citizens. Measurement protocols were also developed to assist the GGD in carrying out future measurements.
The strength of the magnetic field in the vicinity of transformer houses and underground cables decreases with distance and is dependent on the strength of the current at the time of the measurement. The strength of the current is proportional to the amount of electricity used. The arrangement of the cables in the ground also affects the strength of the magnetic field. Consequently, the pilot measurements cannot be considered to be representative of apparently similar situations. The same is true for the magnetic field of household appliances, since both the type and age of the appliance affect the strength of the field. The results do, however, indicate the order of magnitude of the strength of the magnetic field at various distances from sources of magnetic fields.
Prior to the measurements being performed, an inventory was made of currently available data on the strength of the magnetic field in common everyday situations. For overhead power lines, there was sufficient information on the strengths of the field at various distances from the lines. In contrast, data were scarce or outdated for underground cables, transformer houses, household appliances and field strengths in dwellings.