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Electromagnetic Immunity Test Method for Evaluating Device Exposure to Consumer Inductive Wireless Power Transfer (WPT) Systems

Catalog of Regulatory Science Tools to Help Assess New Medical Devices
 

This Regulatory Science Tool (RST) is a lab method for testing medical device electromagnetic immunity to consumer-grade wireless power transfer (WPT) systems as part of assessing Electromagnetic Compatibility (EMC) of medical devices.

Technical Description

This RST provides an EMC immunity test method for evaluating medical device exposure to consumer-grade wireless power transfer (WPT) systems. Test signal parameters were selected based on measured electromagnetic emission characteristics of 13 commercially available consumer-grade WPT products operating in both ping and charging modes, recorded at various separation distances, as detailed in [1]. 

Intended Purpose 

This RST may be used as one approach to characterize medical device exposure to emissions from consumer-grade WPT electronics as part of a broader EMC evaluation strategy. Consumer-grade WPT systems use magnetic induction to charge electronic products such as smartphones, earbuds, or smart watches. While existing EMC medical device consensus standards (e.g., IEC 60601-1-2:2020 [2], which is FDA-recognized [3]) prescribe immunity test methods for a device’s expected electromagnetic environment of use, current editions of these standards do not specify test methods for emerging technologies such as consumer-grade WPT systems. This RST was developed considering available medical device EMC standard approaches (e.g., IEC 60601-1-2:2020).

Testing

Emission characteristics were measured from 13 consumer-grade WPT products that were widely commercially available in the consumer market at the time of developing this RST [1]. WPT system emissions were measured by performing 3D translation of a magnetic field sensor over each WPT system using a robotic arm system. The test frequencies and test levels were selected based on the strongest emissions measured from those WPTs at each separation distance, to represent the risk-conservative upper-bound exposure condition. The modulation profiles were based on the actual modulation envelopes captured from those WPTs.  After developing the test signals and associated test method protocol, the test was applied to a commercially available Holter monitor as a demonstration example of a wearable device with analog and digital electrical components, to illustrate the method’s utility under conditions approximating reasonable worst-case consumer WPT exposure [4]. 

Limitations

  1. This RST is limited to consumer-grade WPT systems that use magnetic induction and operate between 100 – 500 kHz. Emission characterization did not include other types of WPT technology such as large WPT-based electric vehicle charging stations or other WPT systems beyond consumer-grade inductive WPT systems.
  2. This RST was developed using 13 consumer-grade WPTs that were widely commercially available at the time of development. The described emission characteristics may not adequately represent all consumer WPTs available in the market under all operating conditions, and might not represent consumer WPTs with higher power or different operating frequencies that may emerge in the future. 
  3. This RST does not establish test acceptance criteria, nor does it establish acceptable risk for a medical device.
  4. The user may specify the test levels based on reasonably expected minimum separation distances between consumer-grade WPTs and their medical devices, considering the intended use environment of their medical device and relevant use conditions. 

Supporting Documentation

A detailed description of this tool with a table of test signal characteristics is provided in the user manual.

Modulation profiles are available here: [https://github.com/dbp-osel/Consumer-WPT-modulations]

Additional information is available in the following publications:

  1. Y. Ardeshirpour, J. W. Guag, J. L. Silberberg and S. J. Seidman, "Medical Device Electromagnetic Immunity Testing for Exposure to Consumer Wireless Power Transfer Systems - Part I: Emission Characteristics," in IEEE Electromagnetic Compatibility Magazine, vol. 15, no. 1, pp. 48-59, 1st Quarter 2026, https://doi.org/10.1109/MEMC.2026.11435322. 
  2. IEC 60601-1-2, 2020, “Medical electrical equipment - Part 1-2: General requirements for basic safety and essential performance - Collateral Standard: Electromagnetic disturbances - Requirements and tests”, https://webstore.iec.ch/en/publication/59644 
  3. FDA Recognized Consensus Standards: Medical Devices, https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfStandards/search.cfm .
  4. Y. Ardeshirpour, J. W. Guag, J. L. Silberberg and S. J. Seidman, "Medical Device Electromagnetic Immunity Testing for Exposure to Consumer Wireless Power Transfer Systems - Part II: Test Method," in IEEE Electromagnetic Compatibility Magazine, vol. 15, no. 1, pp. 60-68, 1st Quarter 2026, https://doi.org/10.1109/MEMC.2026.11435344.

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