New Edition of EMC Standard for Medical Devices: What Has Changed and When to Apply?
A new fourth edition of the EMC standard IEC EN 60601-1-2 was published in February 2014. It is yet to be fully adopted in the industry and there are many questions on its applicability to different medical devices and changes incorporated. In this article we review the purpose and implications of the change.
What Has Changed and Why?
The main reason for publishing this new edition of the EMC standard is the proliferation of mobile phones. People are carrying them around everywhere, including hospitals. When so many people have a mobile radio transmitter in their pocket, the immunity of medical equipment needs to be extended to a level that will allow the unrestricted use of mobile phones in hospitals and near medical devices. Also, compatibility to other wireless systems like WLAN, TETRA and RFID is included in the additional tests and frequency ranges.
In the previous, 3rd edition, of the standard, the requirements were based on the purpose of the equipment. In the current 4th edition, the requirements are based on the intended use environment of the equipment:
- Professional healthcare facilities (hospitals, clinics)
- Home healthcare environments (other locations)
- Special environments (military, industrial, planes/helicopters, cars etc.)
The standard includes some new definitions:
- Intended use (medical purpose only)
- Normal use (including medical use and transport, maintenance, standby)
One of the key issues is risk analysis by the manufacturer. In the Risk Management File (RMF), Essential Performance (EP) and Basic Safety with regard to electromagnetic disturbances of the equipment to be tested shall be defined. The RMF shall also include and define deviations of functionality and performance during EMC phenomenon. Before any tests can be started, careful planning and good communication between the testing laboratory and the manufacturer are essential. This planning has to be documented in a test plan. The EMC laboratory can support the client in making the test plan.
Changes for the emission requirements are minimal. ITE shall now fulfil CISPR 32 and as an informative change, common mode emissions for patient cables are introduced. In addition, a more detailed guide is given in the 4th edition of the standard for selection of emission class A or B, depending on intended use and location.
Changes for the immunity requirements are numerous and substantial, for example:
- IEC EN 61000-4-2 ESD: higher 8/15 kV test levels are required, connector tests modified
- IEC EN 61000-4-3 Radiated RF: Extended frequency range 80-2700 MHz, 3/10 V/m levels, transmitter exclusion band eliminated
- New test for proximity field immunity: 15 discrete frequencies, levels 9-28 V/m, pulse modulations up to 6 GHz
- IEC EN 61000-4-4 Burst/EFT: Repetition rate has been increased from 5 kHz to 100 kHz
- IEC EN 61000-4-6 Conducted RF: 6V/m test level at ISM frequencies and amateur bands
- IEC EN 61000-4-8 Magnetic immunity: Considerably higher test level of 30 A/m instead of 3 A/m
- IEC EN 61000-4-11 Voltage dips: Modified dips / interruptions
- New tests for vehicle equipment, ISO 7637-2 transients (12 VDC) and emissions according to CISPR 25
- New references to RTCA DO-160G for additional requirements concerning intended use in aircraft
Selected pre-compliance tests are strongly recommended during development process to ensure that the new requirements can be fulfilled by the system.
When to Apply the New Edition of the Standard?
There is no transition period for IEC standards. When a new edition is published, it is valid immediately. In the CB scheme there a no definite rules on when to apply the new edition of a collateral standard. Detailed regulation on transition will be implemented on a national level. However, it is possible to give some guidance, based on IECEE’s Operational Document OD-2055 and private communication with CB experts:
- When a medical device (MD) is tested and certified according to the 2nd edition of the basic standard IEC EN 60601-1, the corresponding EMC standard IEC EN 60601-1-2, ed. 2:2000 + Am.1:2004 is applied
- When a MD is tested and certified according to the 3rd edition of the basic standard, the corresponding EMC standard is IEC EN 60601-1-2, ed. 3:2007. However, it is possible to test and certify the MD against the EMC requirements separately. In that case the 4th edition can be applied
- When the MD is tested and certified against requirements of the 3rd edition + Am1:2012 of the basic standard, it is possible to apply both the 3rd and 4th edition of the EMC standard. However, it should be noted that some particular standards include a dated reference to the EMC standard as normative that should be applied. In spite of that, we do recommend applying the most recent edition
- Within the EU region, presumption of conformity is dictated by the list of harmonised standards that is published in the Official Journal. Unfortunately, there is an ongoing clash between the EU Commission and standardisation organisations that has practically paralysed the list of harmonised standards. Because of that, the manufacturer’s Notified Body has to define what represents the state of the art. In most cases, the newest edition of the standard is the safest option
For more information, please contact:
Product Line Manager
SGS Fimko Oy
t: +358 40 560 9500