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Electromagnetic shielding mats: facts and fiction
1Institute of Clinical Engineering with European Notified Body of Medical Devices, Graz University of Technology, Inffeldgasse 18, A-8010 Graz, Austria. norbert.leitgeb@tugraz.at
Radiation Protection Dosimetry
|December 8, 2006
Summary
Electromagnetic shielding mats do not work as advertised and may even increase exposure to electric and magnetic fields (EMFs). Their effectiveness is often exaggerated, making them a poor investment for consumers seeking EMF protection.
Area of Science:
- Environmental Science
- Electrical Engineering
- Consumer Product Safety
Background:
- Widespread public concern regarding environmental electromagnetic fields (EMFs) has led to a market for shielding products.
- Manufacturers often make unsubstantiated claims about the efficacy of electromagnetic shielding mats.
Purpose of the Study:
- To numerically simulate and evaluate the effectiveness of electromagnetic shielding mats.
- To verify manufacturer claims and expert opinions regarding EMF shielding.
- To assess shielding performance across extremely low frequency (ELF) and radiofrequency (RF) ranges.
Main Methods:
- Numerical simulations were employed to model the performance of shielding mats.
- Investigated the impact of grounding and material conductivity on shielding effectiveness.
- Analyzed manufacturer claims and supporting expert reports for validity.
Main Results:
- Shielding mats failed to meet customer expectations in both ELF and RF ranges.
- Products often exacerbated EMF exposure rather than reducing it.
- Grounding connections and material conductivity did not improve shielding and could worsen field exposure.
Conclusions:
- Manufacturer claims regarding the shielding effectiveness of mats are misleading.
- The acquisition and use of electromagnetic shielding mats are strongly discouraged due to their ineffectiveness and potential to worsen EMF exposure.
- Consumers are advised against purchasing these products based on current evidence.
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