Revised EMC Standard May Emit EU Trouble

Medical Electrical Equipment entering the European Union after November 1, 2004 is required to meet the requirements of the 2001 revision of EN 60601-1-2 "Medical electrical equipment - Part 1-2: General requirements for safety - Collateral standard: Electromagnetic compatibility - Requirements and tests."

Compared to the currently harmonised 1993 edition of the standard, the 2001 revision is considered by EMC experts to be much more detailed and technically relevant, and possibly more difficult to conform to. If your medical device is in design now, or recently completed design, testing to the 1993 vs. the 2001 edition may be an extremely important decision for you because after 1 November, 2004, CE Marking Declarations of Conformity may no longer refer to the 1993 standard.

Performance Criteria Categories

The previous standard identifies the two categories for medical electrical equipment and the new standard defines the two categories: life-supporting and non-life-supporting. The new standard goes further to require specific performance criteria for each category. The life-supporting equipment category is subject to much more stringent requirements in many areas.

One of the most significant requirements of the revised standard is the amount information to be included in the declaration of conformity. Detailed examples and decision tables are provided to assist manufacturers in the process of preparing the declaration of conformity to meet the requirements of the standard.

In addition to meeting the technical requirements, manufacturers will have to review existing compliance documentation to ensure that their declarations of conformity show the correct standards and that the documentation provided to the user is adequate. Technical experts should be consulted in case of questions.

Preparing the Proper Test Plan

Determining the appropriate test plan is critical to the success of your compliance. The test plan development process presents a challenge in that numerous factors must be considered before you begin compliance testing.

For example:

Is the system patient-connected or not?
Is it portable or stationary?
Will it be used in shielded rooms?
How many different interfaces are there?
How many cables are required to use it?
What are the processor speeds?
What clock frequencies does it operate on?
In what environment will it be used?
In which countries will it be used?
Under what conditions will it be used?

Comparison Overview
Size	EN 60601-1-2:1993 16 pages (11 normative, 5 informative)	EN 60601-1-2: 2001 100 pages (50 normative, 50 informative)
Labeling, accompanying documents, and manufacturer's declaration	1/2 page	19 pages
Performance criteria for immunity testing	1 paragraph	3 pages
Figures and tables	1	32
Definitions	3 pages	4 pages

When developing a new product, designers should first identify and work with tested and approved components. If the power supplies, filters and other assemblies are already tested and certified to the revised standard, your product stands a better chance of success. However, integrating compliant components does not necessarily mean that the end product will test compliant. Every system needs to be evaluated in its final form, and the final tests required consider the whole - each component, all cabling and the interaction of all components.

Technical Comparison
	EN 60601-1-2:1993 All	EN 60601-1-2:2001 Non-Life Support	EN 60601-1-2:2001 Life-Support
Electro-Static Discharge (ESD)	IEC801-2 ±3 kV contact ±8kV Air	IEC 61000-4-2 ±6 kV contact ±8 kV air	IEC 61000-4-2 ±6 kV contact ±8 kV air
Radiated E-Field Immunity *	IEC 801-3 26-1000 MHz 3 V/m 1 kHz AM 80% (IEC 801-3 method)	IEC 61000-4-3 80 MHz to 2.5 GHz 3 V/m 1 kHz AM 80% (IEC 61000-4-3 method)	IEC 61000-4-3 80 MHz to 2.5 GHz 10 V/m 1 kHz AM 80% (IEC 61000-4-3 method)
Electrical Fast Transient Immunity (EFT)	IEC 801-4 ±1 kV mains ±0.5 kV I/O>3m	IEC 61000-4-4 ±2 kV power supply ±1 kV input/output	IEC 61000-4-4 ±2 kV power supply ±1 kV input/output
Surge Immunity	IEC 801-5 ±1 kV DM ±2 kV CM	IEC 61000-4-5 ±1 kV DM ±2 kV CM	IEC 61000-4-5 ±1 kV DM ±2 kV CM
RF Conducted Immunity *	Not specified	IEC 61000-4-6 3 Vrms 150 kHz to 80 MHz	IEC 61000-4-6 3 Vrms 150 kHz to 80 MHz outside ISM bands 10 Vrms 150 kHz to 80 MHz in ISM bands
Power Frequency Magnetic Field Immunity	Not specified	IEC 61000-4-8 3 A/m	IEC 61000-4-8 3 A/m
Voltage Dips & Interrupts *	Not specified	IEC 61000-4-11 >95 % dip for 0,5 cycle 60 % dip for 5 cycles 30 % dip for 25 cycles >95 % dip for 5 sec	IEC 61000-4-11 >95 % dip for 0,5 cycle 60 % dip for 5 cycles 30 % dip for 25 cycles >95 % dip for 5 sec
Conducted Emissions	EN 55011 Class A	EN 55011, EN 55014, EN 55015, EN 55022 depending on function Refer to 36.201.1	EN 55011, EN 55014, EN 55015, EN 55022 depending on function Refer to 36.201.1
Radiated Emissions	Class A	EN 55011, EN 55014, EN 55015, EN 55022 depending on function Refer to 36.201.1	EN 55011, EN 55014, EN 55015, EN 55022B depending on function Refer to 36.201.1
Harmonics	Not specified	EN 61000-3-2	EN 61000-3-2
Flicker	Not specified	EN 61000-3-3	EN 61000-3-3

* Indicates more stringent requirements for life supporting equipment

Note 1: This comparison information shows the general technical requirements for most equipment. Certain equipment (e.g. equipment monitoring physiological parameters) may be subject to additional or different requirements. Familiarity with the full standard is necessary for the development of a valid test plan for specific equipment.

Note 2: The highlighted items show areas where the requirements of the 2001 version are more stringent than those of the 1993 version.

Note 3: Do not make any decisions based on this chart alone; take the time to consult with your CRO Group consultant to confirm that your test plan and documentation adequately meet the new requirements, or to arrange for a test plan to be prepared for your product.

Revised EMC Standard May Emit EU Trouble

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