EU Directive 2004/40/EC
“Electromagnetic Fields”
The Negative Impact on
MRI Clinical Applications
COCIR EMF TASK FORCE
page 1 of 49
History, Status and
Context
page 2 of 49
EC Directive: history and status
• In 1989, the European Commission was mandated to
develop Directives protecting workers from potential
hazards caused by “physical agents”
• 4 Directives have been developed
– vibration (2002/44/EC)
– acoustic noise (2003/10/EC)
– electromagnetic field (EMF) (2004/40/EC)
– optical radiation (2006/25/EC)
• EMF Directive published in April 2004
• Transposition into national law within 4 years,
i.e. by 2008
Sept. 2006, page 3
Sept. 2006, page 4
General COCIR statements
Facts:
Directive 2004/40/EC covers minimum health and safety
requirements regarding the exposure of workers arising from
electromagnetic fields. The directive defines exposure limits up to
300 GHz
The directive stipulates “in any event, workers shall not be
exposed above the exposure limit values”
Area of concern for COCIR:
The application of electromagnetic fields in Magnetic Resonance
Imaging (MRI)
COCIR issues:
• Currently, these exposure limits are regularly exceeded with NO
REPORTED NEGATIVE EFFECTS on either workers or >500,000
patients worldwide.
• The EC directive will hamper use of MRI and prohibit future
medical applications of MR.
Sept. 2006, page 5
The Aims and Scope of
the EMF Directive
page 6 of 49
The EMF Directive
• Aims to protect workers from acute exposure to electromagnetic
fields (EMF)
• Defines exposure limits for EMF for frequencies ranging up to 300
GHz
– These limits are based on the ICNIRP Guidelines
(ICNIRP = International Commission on Non Ionizing Radiation Protection)
which considered short term effects (such as dizziness, peripheral nerve
stimulation, temperature effects….) reported at fields levels not used in
MRI.
– Peripheral nerve stimulation is not considered by ICNIRP for workers. The
ICNIRP limit in the kHz range is based on effects ion the central nervous
system
• An explicit statement in the directive states that long term effects are
excluded from the scope of the directive (e.g. carcinogenic effects...)
and hence the directive applies only to acute effects.
Sept. 2006, page 7
The EMF Directive
• Limit values are based on possible short term health effects.
According to the WHO definition, this includes “negative
effects on personal well-being”.
• “In any event, workers shall not be exposed above the
limit values”.
• Using the “precautionary principle”, these exposure limits
are far below those which may produce known
physiological effects and those applied to patients.
Result: a severe conflict with the application of MR
Sept. 2006, page 8
In the workplace…
The Directive applies in the same way to all
workplaces with no special provision or
exemption for the medical environment.
Sept. 2006, page 10
What current
MRI safeguards
exist?
Sept. 2006, page 13
“The” MR safety
standard is
IEC 6061-2-33
Sept. 2006, page 14
Progress on IEC 60601-2-33
• IEC MT 40 is currently working on a 2nd amendment to the
IEC 60601-2-33, which specifically addresses EMF exposure for
MR workers. There proposals are
– Static magnetic field: proposed limit value is equal to the value for
the patient (4T) and working at higher field strength is subject to
approval from local ethics commission
– Gradients: Proposed limit value is equal to the the value for the
patient, which is based on the level required to produce peripheral
nerve stimulation. No peripheral nerve stimulation will be observed
by the MR worker. Unless he is bending into the scanner…
– SAR: the proposed values for workers are equal to the values for the
patient (and thus the whole body SAR = 4W/kg estimated to result in
a core temperature increase of max. 10 C). But that is if the worker
would be inside the transmit coil…
• Status: 2nd amendment distributed as Committee Draft for Vote;
result due Nov/2006
Sept. 2006, page 16
Conflicts between the EMF
directive and scientific
opinion
page 17 of 49
Bodies expressing concern
and their relevant actions
• Intensive discussion have started at Europe and national level, e.g.
the UK House of Commons select-committee report “Watching the
Directives: Scientific Advice on the EU Physical Agents
(Electromagnetic Fields) Directive” which is very critical, and
activities in France, Finland, Germany, Netherlands……
• ISMRM / ESMRMB: Activities of the Safety Committees,
– publishing of information on their websites
– promotion of scientific work on MR
• COCIR:
– determining a common strategy for MR manufacturers
– comments submitted to European Commission
– participating in a COCIR Task Force on the practical
implementation of the EC Directive
• IEC MT40:
– writing an amendment to the MR safety standard
IEC 60601-2-33 for the safety of MR workers by defining
exposure limit values (which are different to those from
the current EC Directive)
Sept. 2006, page 18
Examples of negative
impact of the EMF
directive on MRI and the
applications at risk
page 27 of 49
Applications at risk
• Emergency cases (e.g. coma patients…)
• Special populations (e.g. babies…)
• Interventional applications
• Research and innovation in Europe
(e.g. MR PET…)
These result from the exposure limits for SAR and currents
induced by changing magnetic fields
• All applications of MR are no longer
possible....
....if currents induced by movement in the static field are not
excluded!
Sept. 2006, page 30
COCIR statements and
recommendations
page 32 of 49
COCIR Questions
• EC directives “noise” and “vibration” contain a chapter “derogations”.
– Why are we told “derogations” are not possible for the
“EMF” directive for medical uses where an existing
International Standard exists?
• The directive only applies to acute effects.
– Why are workers treated differently to patients?
• IEC 60601-2-33 (Particular requirement for the safety of magnetic
resonance equipment for medical diagnostic) is a perfect candidate to
assure safety in the MRI environment.
– Why is this not being used?
• The exposure level for the MR worker close to the edge of the bore of
the system both for the RF and the gradients is difficult to measure
and must therefore be estimated based on simulations.
– Do we need more research in this area?
Sept. 2006, page 33
Consequences of the implementation
of the EMF directive
• If partially implemented i.e. the effects of moving
in a magnetic field are ignored, then many existing
and developing applications will be prevented.
• If the directive is implemented as published, then
MRI will be unusable.
In each case, the treatment of patients will be
compromised due to the lack of diagnostic
imaging, or they will be subjected to
unnecessary exposure to ionising radiation.
Sept. 2006, page 34
COCIR Recommendations:
• A general exemption from the scope of
the EMF Directive for personnel working in
electromagnetic fields in connection with
the use of MR is enacted and the
International Safety standard, specifically
designed for MRI*, is adopted.
• Research is undertaken to establish the
real consequences of exposure to EMF at
the levels used in MRI, and a risk benefit
analysis is then undertaken.
(* IEC 60601-2-33)
Sept. 2006, page 35
However, …
“MR services are among the most powerful, yet safest,
of all diagnostic procedures to be developed in the
history of modern medicine”
(Emanuel Kanal)
Sept. 2006, page 36