In situ magnetic field exposure and ICNIRP-based safety distances for electronic article surveillance systems.

Electromagnetic radiation of electronic article surveillance (EAS) systems was investigated in situ for both the detection gate panels and the activators and deactivators. 'Safety distances' for the general public, defined as the distances outside which the magnetic field levels of the EAS systems do not exceed the The International Commission on Non-ionising Radiation Protection reference levels, were determined. Additionally, temporal and frequency behaviour, and signal waveforms were investigated. For the detection gates, the spatially averaged fields exceeded the reference levels for five of the six investigated systems. For the (de)activators, the spatially averaged fields did not exceed the reference levels. Maximal fields up to 148.0 A m(-1) were measured from 20 cm on. The exposure ratios varied from 8 to 13 for EM, from 6 to 8 for AM and from 0.008 to 1.8 for RF systems. Safety distances were maximally 111 cm for EM, 77 cm for AM and 35 cm for RF systems.