EU magnetic field strength rules gain final approval

June 2, 2004

Proposed European Union legislation governing exposure to electromagnetic fields has received its final stamp of approval. The new directive, which affects the use of MRI equipment, is now set to become law. The EU's EMF directive sets minimum health and

Proposed European Union legislation governing exposure to electromagnetic fields has received its final stamp of approval. The new directive, which affects the use of MRI equipment, is now set to become law. The EU's EMF directive sets minimum health and safety requirements to protect workers exposed to electromagnetic fields. These include regular health surveillance of personnel, comprehensive risk assessment of working environments and use of protective measures, and appropriate equipment to minimize dosage.

Possible long-term health effects related to cumulative exposure are not covered, given the lack of conclusive scientific evidence for a causal relationship between EMF and cancer. Exposure of individuals undergoing medical exams is also excluded. Significantly, however, interventional radiologists or surgeons may have to wear a form of EMF dosimetry badge.

News that EMF legislation was in the works initially provoked concern within the medical imaging community (SCAN 11/12/2003). Researchers and clinicians in Europe raised fears that vendors may be forced to reengineer MR scanners, pushing up manufacturing, purchasing, installation, and operating costs. Others warned of a two-tier system for MRI, with U.S. teams forging ahead on ultrahigh field systems barred from Europe.

Alterations made to the draft document during its passage through the European Parliament may appease critics. Concessions have been made in the final version, though EU regulators have not met every wish of the MRI community, said Hans Bursig, secretariat general of the European Coordination Committee of the Radiological, Electromedical, and IT Industries (COCIR).

COCIR had lobbied regulators to exempt medical MR equipment from the new EMF rules, on the grounds that MR scanners were already subject to comprehensive regulation under the EU's Medical Devices Directive. This stance was supported by the International and the European Societies for Magnetic Resonance in Medicine and Biology (ISMRMB and ESMRMB), as well as by the European Association of Radiology (EAR). But exemption requests fell on deaf ears. Future use of MRI for diagnosis and/or treatment in any hospital or clinic within an EU member state will be bound by the new rules.

The legislation does not, however, put an explicit limit on the permitted field strength of MR scanners. Early versions of the directive cited restrictions to static field strength, though these have been removed from the final document, Bursig said. Restrictions on switching, or "time-varying" electromagnetic fields remain.

"Our experts tell us that existing equipment in clinical practice will not face any problems from this directive, but this may change as stronger magnets leave research laboratories and enter clinical environments," Bursig said. "We were very concerned when we saw the first draft of this directive, and we still have some reservations with regard to the future. But all in all, we believe that our customers and users of MRI equipment will be able to live and work with this legislation."

The majority of MRI facilities will simply have to adopt new working practices, he said. He suggested setting up procedures for monitoring workers' daily EMF dose as a possible instance. Rules governing EMF exposure over a fixed time period may have more serious implications for interventional MRI, though. Complex neurointerventions performed over several hours could be particularly affected.

"This may become problematic, but we don't know for sure," Bursig said. "We would have liked to have had a general exemption for medical devices to make sure that this didn't happen."

EU regulators have agreed to review the legislation in five years, at which point restrictions on static field strengths could be added, Bursig said. The review stage would also present an opportunity for the MRI community to explain how the directive has affected medical imaging.

It will still be a while before radiologists, hospital managers, and MRI vendors feel the full weight of the EU's EMF regulations. The approved directive must first be signed by the president of the EU Council and then published in the Council's official journal. All countries within the newly expanded EU will then have four years maximum to set up a legal framework for compliance.

"The next problem-or set of problems-may arise as member states transpose this directive into national law," Bursig said. "They may stick to the directive, they may have additional requirements, or they may just do something different. Some countries, like Germany, for example, already have worker protection rules with regard to electromagnetic fields."