F2 Labs
What FDA Reviewers Are Looking for in Medical Device EMC Submissions

Wendy Fuster, President

A manufacturer completes IEC 60601-1-2 testing. The product passes, the report is submitted to the FDAand then questions come back.

What was considered Essential Performance? How were the acceptance criteria established? Was the device's intended-use performance monitored? What happens when it is exposed to RFID readers, electrosurgical equipment, wireless power systems, or other emitters it may encounter in normal use?

Over the past year, we have noticed FDA reviewers looking more closely at these questions. In many cases, there is nothing technically wrong with the testing that was performed. The problem is that the test program and report do not provide enough information to show what was monitored, why the criteria were appropriate, or whether the testing represented the device's actual use environment.

A passing IEC 60601-1-2 report is still important. It just may not answer every question the reviewer has.

Essential Performance Is Receiving More Scrutiny

Essential Performance is not a new concept, but we are seeing more attention paid to how it is defined and how consistently it is addressed throughout the submission.

Too often, the documentation says that the device must “operate as intended” or experience “no unacceptable degradation.” Those statements do not give the laboratory enough information to develop a meaningful test plan. They also do not tell the FDA reviewer what performance was actually evaluated.

The manufacturer should identify which clinical functions matter, how much change is acceptable and at what point a degradation could create unacceptable risk.

For an infusion device, it may not be enough to show that fluid continued to move during the test. The manufacturer may need to define the allowable change in delivery rate, how long the rate will be measured, what the alarms must do and whether a temporary interruption is acceptable.

For a monitoring device, keeping the display powered may not be the important issue. The real question may be whether the displayed value remains within a defined tolerance and whether an incorrect value could affect a clinical decision.

These decisions need to be made before testing. They affect the test setup, operating modes, software settings, accessories, monitoring equipment and acceptance criteria. In some cases, they affect how the test sample must be built.

We are also seeing problems when the different project documents do not agree. The risk-management file may identify certain important functions, while the EMC test plan monitors something else. The report may allow a temporary loss of performance that is not addressed in the risk analysis. A particular standard may define Essential Performance that was not carried into the manufacturer's criteria.

The equipment may have passed every applied test, but the inconsistencies still raise questions.

A manufacturer can conclude that a device has no Essential Performance. That may be valid, but the conclusion should come from the risk-management process. It should not be the default answer because Essential Performance was never discussed.

IEC 60601-4-2 Is Becoming Part of the EMC Evaluation

We have also noticed more FDA attention on IEC 60601-4-2.

IEC 60601-1-2 addresses electromagnetic compatibility as it relates to Basic Safety and Essential Performance. IEC 60601-4-2 looks more broadly at whether the equipment continues to provide the performance needed for its intended use during electromagnetic disturbances.

That distinction matters because a device can avoid an immediate safety hazard and still fail to provide the medical function for which it is being marketed.

A device may remain powered and not produce a dangerous output, but it could temporarily display inaccurate information, stop recording data, lose communication, or fail to provide another function relied upon by the user. Whether that is acceptable depends on the intended use, how long the condition lasts, whether the user can recognize it and what effect it could have on the patient.

FDA reviewers are increasingly expecting manufacturers to address this broader performance question. In many cases, the IEC 60601-4-2 evaluation can be completed during the same test sessions used for IEC 60601-1-2. That is much easier when it is planned from the beginning.

The laboratory needs to know which additional functions must be exercised and monitored. The manufacturer needs to provide measurable criteria for those functions. The test setup must be capable of detecting a change while the electromagnetic disturbance is being applied.

This is difficult to add after testing has been completed. The correct functions may not have been operating. The needed performance data may not have been recorded. The original test samples, software version, accessories, or monitoring setup may no longer be available.

We recently discussed this with a manufacturer (who previously had his EMC testing done elsewhere) that believed the EMC portion of its program was complete because the device had passed IEC 60601-1-2. The testing itself was acceptable, but the broader intended-use performance had not been evaluated. Addressing that later required additional review and planning that could have been handled during the original test program.

Common Electromagnetic Emitters Are Still Catching Manufacturers Off Guard

Common EM emitters testing has been discussed for several years, but we continue to hear from manufacturers who first learn about it after submitting to FDA.

IEC 60601-1-2 represents many electromagnetic disturbances. It does not necessarily address every emitter the device may encounter in its intended environment.

Depending on the product and where it will be used, the manufacturer may need to consider RFID readers, security systems, metal detectors, NFC equipment, wireless power systems, cellular transmitters, electrosurgical equipment, MRI equipment, or diathermy equipment.

Not every device needs to be tested against every emitter. The decision should come from the intended-use environment, the likelihood of exposure and the possible result if interference occurs.

A device used in a hospital may be exposed to RFID systems or electrosurgical equipment. A wearable or home-use device may be more likely to encounter smartphones, wireless chargers, security gates, or NFC transmitters. The risk assessment should identify which sources are reasonably foreseeable and whether the standard EMC test program addresses them adequately.

When it does not, the manufacturer may need additional testing or a technical justification.

One pattern we continue to see is a company completing IEC 60601-1-2 testing, submitting to FDAand then receiving a question about common emitters. The company must reopen the risk assessment, develop a supplemental test plan, obtain more samples, recreate the setup and update the submission.

What appears to be a small addition can quickly affect the schedule.

This is especially difficult when the engineering team has moved to another project or the exact version of the tested device is no longer available. A discussion about intended environments at the start of the project usually identifies these issues before they become a regulatory delay.

A Passing Report May Not Be a Submission-Ready Package

Manufacturers often compare laboratory proposals by looking at price and test days. That is understandable, but the scopes may not be equivalent.

One laboratory may quote only the standards listed in the request. Another may include work related to Essential Performance, IEC 60601-4-2, common emitters, home healthcare, wireless functions, applicable particular standards, or FDA-specific documentation.

The narrower quote may look less expensive. It is not less expensive when missing work is discovered during the FDA review.

At F2 Labs, we spend time trying to understand what the client is actually likely to need, not only what is written in the initial request for quotation. We ask where the device will be used, what it does clinically, which functions are tied to risk, whether it contains wireless technology and whether the report is intended to support an FDA submission.

Clients do not always know every test that may be expected. That is normal. It is part of the reason they are working with a compliance laboratory.

Our responsibility is to identify likely test requirements before the client commits to a test plan, budget and schedule. That can make the initial scope look more expensive than a proposal that includes only the minimum request. At F2 Labs, we try to help you avoid unexpected fees and issues by clearly outlining the complete project requirements from the start.

The risk-management file, test plan, report, labeling and submission should agree on what was evaluated, how it was monitored, which configurations were tested and what performance was considered acceptable. When those documents do not agree, a passing result may not be enough to close the reviewer's questions.

These Decisions Should Be Made Before Testing

By the time the equipment reaches the EMC chamber, the manufacturer and laboratory should already understand what functions need to be monitored, what limits apply, what degradation is acceptable and which real-world emitters need to be considered.

IEC 60601-1-2 remains a critical part of medical device compliance. Manufacturers should not assume, however, that completing the standard automatically addresses every FDA expectation.

Essential Performance, intended-use performance under IEC 60601-4-2, common emitters, applicable particular standards and the device's intended environment should be considered together when the test plan is developed.

At F2 Labs, our goal is to help clients understand the likely scope before testing begins. It is much easier and less costly to address these issues while the plan is being developed and the product team is still available than after FDA has already asked the question.