What is the EMC Compliance Process for a New Medical Device?

Congratulations! You are on the path to bringing your new design to the US and EU markets. This article will cover the four steps to achieving your compliance goals. It will also give you pointers on the process if you did not pass the first time around.

PART 1: REGULATORY FRAMEWORK OVERVIEW

United States (FDA):

• Regulatory Authority: U.S. Food and Drug Administration (FDA).

• Governing Law: Federal Food, Drug, and Cosmetic Act (FD&C Act).

• Market Entry Pathways:

• 510(k) premarket notification for substantial equivalence.

• De Novo classification request for novel, low-to-moderate risk devices.

• Premarket Approval (PMA) for high-risk Class III devices.

European Union (EU):

• Regulatory Authority: National Competent Authorities and Notified Bodies.

• Governing Law: Medical Device Regulation (MDR) (EU) 2017/745.

• Market Entry: CE Marking via conformity assessment procedure.

PART 2: EMC COMPLIANCE PROCESS

A. Design and Risk Analysis Stage

1. Determine the device's electromagnetic environment and use cases (hospital, home, mobile, etc.).

2. Classify device risk level (U.S.: Class I, II, III; EU: Class I, IIa, IIb, III).

3. Develop an EMC Risk Management Plan per ISO 14971.

4. Establish essential performance criteria and allowable deviation limits under electromagnetic interference.

Relevant Standards:

• ISO 14971: Risk management for medical devices.

• IEC 60601-1-2: General requirements for EMC in medical electrical equipment.

• CISPR 11: Limits and methods of measurement of radio disturbance for ISM equipment.

B. Pre-Compliance Testing (During Development Phase)

1. Set up in-house or outsourced testing to simulate EMC conditions and identify design flaws early.

2. Use near-field probes, spectrum analyzers, EMI receivers, LISNs, TEM cells, and immunity test generators.

3. Perform emission and immunity testing in an uncontrolled (preliminary) environment.

Test Categories Include:

• Conducted emissions (CISPR 11).

• Radiated emissions (CISPR 11).

• Electrostatic discharge (IEC 61000-4-2).

• Radiated RF immunity (IEC 61000-4-3).

• Electrical fast transients (IEC 61000-4-4).

• Surge immunity (IEC 61000-4-5).

• Conducted RF immunity (IEC 61000-4-6).

• Voltage dips and interruptions (IEC 61000-4-11).

1. Refine hardware design through:

• Shielding.

• Grounding improvements.

• Layout optimization.

• Filter integration.

C. Final Compliance Testing (Before Regulatory Submission)

1. Perform full, formal EMC testing at an ISO/IEC 17025-accredited laboratory.

2. Document all procedures, conditions, and results under validated protocols.

3. Demonstrate compliance with the relevant harmonized or recognized standards.

For U.S. FDA Submission:

• Include test reports from EMC testing conforming to IEC 60601-1-2 (Edition 4.1)

• Follow FDA guidance titled "Information to Support a Claim of Electromagnetic Compatibility (EMC) of Electrically-Powered Medical Devices."

• Submit as part of the technical documentation for 510(k), De Novo, or PMA.

• Include a risk management file, labeling with EMC environment specification, and justification for immunity levels.

For EU CE Marking:

• Perform conformity assessment against harmonized EMC standards such as EN 60601-1-2 and EN 55011.

• Compile results into a technical file, including the Declaration of Conformity.

• Submit to Notified Body for assessment (mandatory for Class IIa, IIb, and III devices).

• Once approved, affix the CE Mark and maintain post-market surveillance and updates.

Additional Considerations:

• RoHS compliance (Restriction of Hazardous Substances Directive).

• REACH compliance (chemical safety regulation).

• Consider wireless coexistence testing for devices with Bluetooth, Wi-Fi, ZigBee, etc.

PART 3: STANDARDS SUMMARY BY FUNCTIONAL AREA

• IEC 60601-1-2: General EMC requirements for medical electrical equipment.

• CISPR 11 / EN 55011: RF emissions for ISM equipment.

• IEC 61000-4-2: Electrostatic discharge immunity.

• IEC 61000-4-3: Radiated RF electromagnetic field immunity.

• IEC 61000-4-4: Electrical fast transient/burst immunity.

• IEC 61000-4-5: Surge immunity.

• IEC 61000-4-6: Conducted RF immunity.

• IEC 61000-4-11: Voltage dips and interruptions immunity.

• ISO 14971: Risk management for medical devices.

PART 4: SUBMISSION AND MARKET ENTRY STEPS

FDA Submission Process:

1. Prepare the technical submission, including EMC test reports, risk management documentation, labeling, and intended use environment.

2. Submit through the appropriate regulatory pathway (510(k), De Novo, or PMA).

3. Respond to any additional information requests or testing clarifications from the FDA.

4. Await clearance or approval before entering the U.S. market.

CE Marking Process in the EU:

1. Prepare the complete technical file, including EMC data and conformity assessments.

2. Work with a Notified Body for review if the device is Class IIa, IIb, or III.

3. Submit Declaration of Conformity and apply CE Mark upon successful review.

4. Register the device with the appropriate EU national authority and maintain compliance records.

What does the designer do if the product does not pass compliance?

Suppose your medical device fails EMC compliance testing. In that case, this is when most companies call on us, Elexana.

Or, the designer and engineering team must take a structured, iterative approach to identify the root cause and redesign the product to meet regulatory requirements. Here’s what happens next:

1. Review Test Report and Failure Data

• Examine the official test results in detail.

• Identify which test(s) failed (e.g., radiated emissions, ESD immunity).

• Note frequency ranges, severity levels, and environmental conditions that caused the failure.

2. Conduct Root Cause Analysis

• Replicate the failure in-house or in a controlled environment.

• Use near-field probes, spectrum analyzers, current probes, and oscilloscopes to pinpoint EMI sources.

• Map failure to specific subsystems, such as:

• Switching power supplies.

• High-speed digital interfaces.

• Poor PCB layout or grounding.

• Inadequate shielding or filter design.

3. Implement Design Corrections

Depending on the failure, mitigation strategies may include:

For Radiated or Conducted Emissions Failures:

• Add or improve EMI filters on power lines (e.g., LC filters, common-mode chokes)

• Optimize PCB layout:

• Shorten high-speed traces.

• Improve return paths.

• Add ground planes.

• Add or enhance shielding around noisy components.

• Replace switching regulators with lower-EMI designs or add spread-spectrum modulation.

For Immunity Failures (e.g., ESD, radiated RF):

• Add transient voltage suppression (TVS) diodes

• Isolate sensitive analog circuitry.

• Increase spacing between high-voltage and logic signals.

• Improve enclosure grounding and bonding.

• Use ferrite beads and capacitive bypassing on I/O lines.

4. Update Risk Management and Documentation

• Document the changes and rationale per ISO 14971.

• Reassess any risks introduced by modifications.

• Update the design history file (DHF) and technical file for regulatory submission.

5. Retest the Device

• Perform internal pre-compliance testing to confirm the fix before returning to the lab.

• Schedule a partial or full re-test at the accredited EMC lab, depending on the scope of changes.

• Ensure any new components or board revisions are validated.

6. Finalize and Resubmit

• Include revised test results in the submission (FDA or CE).

• If the review is under 510(k) and changes are significant, the FDA may require additional documentation or delay clearance.

• For CE marking, the Notified Body may require a repeat of the conformity assessment.

Key Tip: Many compliance failures stem from early-stage design decisions. Performing thorough EMC pre-compliance testing during prototyping significantly reduces the risk of failure at the final compliance stage.

ELEXANA can help you achieve compliance. Please don't hesitate to contact us via the Contact page.