Magnetic Field Assessment of Consumer Products

Electromagnetic fields come from many well-known sources like radio and television broadcast signals and the increasingly ubiquitous cell phones.  In addition to these sources operating in the radio frequency (RF) portion of the electromagnetic spectrum there are many sources which operate at much lower frequencies.  The power grid in the North America and in Europe operates at an alternating current (AC) frequency of 60 Hz, and 50 Hz, respectively.  Anything connected to the power grid (e.g., consumer electronics) may therefore produce AC and/or RF fields.  Finally, permanent magnets (increasingly common in consumer electronics) produce a 0 Hz (or DC) magnetic field.  Exponent engineers have extensive experience in evaluating both the electromagnetic characteristics of a source as well as the potential effects of these sources on other consumer devices such as those for medical use.

Services we offer clients related to DC/AC/RF sources, include:


  • Design and Manufacturing
  • Reliability
  • Risk Assessment
    • FMEA
    • FTA
    • Failure Analysis
    • RF Safety

Specific capabilities that Exponent consultants employ to answer clients’ needs may include:


  • Nearfield sub-millimeter precision 3D magnetic field mapping of DC/AC/RF magnetic fields from consumer electronics.
  • Site-evaluation to measure DC/AC/RF for potential EMI/EMC.
  • Personal/site inspection for exposure assessments
  • Computational modeling of electric and magnetic fields and device operation
  • Electromagnetic compatibility evaluation of electromagnetic fields (AC/DC/RF) for medical device safety evaluations.

Exponent also has extensive in-house testing capabilities including an anechoic chamber for high-dynamic range laboratory measurements, as well as susceptibility analysis in addition to sensitive portable measurement equipment for in-situ field testing (DC to daylight).  Previous measurements using this equipment have been used to make measurements with a distributed average noise level of between -161 and -172 dBm miles from the nearest plug-in power source.

Professionals