Extremely strong magnetic fields at the frequencies used in an electromagnetic articulometer (EMA) system may pose a risk to the health of a subject. To avoid such risks, the field strengths produced by any EMA system should be measured, and compared to published permissible exposure standards. This Letter reports measurements of the 2–50 kHz magnetic field strength of the Carstens Articulograph AG100. The measured field strength (35 μT at a distance of 7.5 cm) is permissible under local standards in Austria, Germany, the UK, and the USA (except Massachusetts), but may be impermissible under the 1995 European Community Prestandard, and in Canada.
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