MDR EMC requirements live in Annex I of Regulation (EU) 2017/745 — specifically Section 14.2(d), which requires devices to be designed and manufactured so that risks linked to reasonably foreseeable external influences, including electromagnetic disturbances, are removed or reduced as far as possible, and Section 17.1, which requires electronic programmable systems to perform reliably in their intended environment. The MDR does not specify test methods for EMC. EN 60601-1-2:2015+A1:2021 is the harmonised collateral standard that, when applied correctly, gives presumption of conformity with those EMC-related obligations for medical electrical equipment. The standard is the tool. The MDR is the obligation. Founders who skip EMC design until the test lab visit almost always pay for the schematic twice.

By Tibor Zechmeister and Felix Lenhard. Last updated 10 April 2026.

TL;DR

  • EMC obligations under MDR come from Annex I Section 14.2(d) (resistance to electromagnetic disturbances) and Annex I Section 17.1 (reliability of electronic programmable systems in their intended environment). These sections state the outcome; they do not prescribe how to prove it.
  • EN 60601-1-2:2015+A1:2021 is the harmonised collateral standard for EMC of medical electrical equipment. It is applied on top of EN 60601-1:2006+A1+A12+A2+A13:2024 — the general standard — not instead of it.
  • EMC has two halves: emissions (what your device radiates or conducts into its environment) and immunity (how your device behaves when the environment radiates or conducts into it). Both halves must be addressed for any device with electronics.
  • Immunity is risk-based. EN 60601-1-2:2015+A1:2021 ties immunity pass/fail criteria to the device's essential performance and basic safety, defined against ISO 14971 risk management. No essential performance on paper means no valid EMC immunity test.
  • Designing for EMC at the schematic and enclosure stage is cheap. Chasing EMC in the test lab after first tape-out is expensive. This is the single most consistent cost multiplier we see in startup projects that skip pre-compliance.

What EMC is and why the MDR cares about it

Electromagnetic compatibility is the property of a device to function correctly in its intended electromagnetic environment without introducing intolerable electromagnetic disturbances to anything else in that environment. In plain language: your device has to survive the hospital's electromagnetic weather, and it cannot create weather that knocks out the neighbour.

The MDR cares about this for a simple reason. A medical device that resets itself when a mobile phone transmits nearby is not safe. A monitor whose alarm fails to trigger because of conducted noise on the mains is not safe. A device that radiates enough energy to corrupt the signal of the infusion pump on the next trolley is not safe. All three failure modes are electromagnetic. All three are invisible to a casual bench test. All three are exactly what the MDR Annex I requirements in Section 14.2(d) and Section 17.1 exist to prevent.

Section 14.2(d) of Annex I addresses risks related to reasonably foreseeable external influences, including electromagnetic disturbances. Section 17.1 requires devices incorporating electronic programmable systems to be designed to ensure repeatability, reliability, and performance in line with their intended use, and to include adequate means to eliminate or reduce as far as possible the risks or impairment of performance that arise from foreseeable environmental conditions. Together, these sections create a legal obligation that the device works in the real electromagnetic environment of the intended use — not in an idealised lab with no radios.

The MDR does not tell you how to demonstrate this. That is where EN 60601-1-2:2015+A1:2021 enters.

EN 60601-1-2 as the harmonised route

EN 60601-1-2:2015+A1:2021 is titled "Medical electrical equipment — Part 1-2: General requirements for basic safety and essential performance — Collateral Standard: Electromagnetic disturbances — Requirements and tests." It is a collateral standard, which means it modifies and extends the general standard EN 60601-1:2006+A1+A12+A2+A13:2024 on the specific topic of EMC. It is never applied on its own; it is always applied in combination with the general standard.

When EN 60601-1-2:2015+A1:2021 is listed as a harmonised standard in the Official Journal of the European Union for a given MDR provision, following it gives presumption of conformity with the corresponding MDR requirement. In practice, this means that if your device passes the tests specified in this standard with the acceptance criteria tied to your documented essential performance, the Notified Body presumes your device meets the EMC-related obligations in Annex I. Any other route to demonstrating EMC conformity exists in principle but has no realistic path through a Notified Body review.

The standard approaches EMC as a risk management task. It is built to be applied on top of a live ISO 14971 risk management file, not alongside an empty one. Teams that try to run EMC testing without first defining essential performance and basic safety in risk terms find out that the test lab cannot define the acceptance criteria for them.

The two halves — emissions and immunity

EMC has two halves, and they are tested separately, for different reasons.

Emissions is the half that asks: what is your device putting out into the electromagnetic environment, and is it below the limits that protect other equipment? Emissions come in two flavours. Radiated emissions travel through space as electromagnetic waves from the enclosure, cables, and any antenna-like structures on the device. Conducted emissions travel through the mains cable or any other wired connection back into the power grid or the attached network. The limits on both flavours depend on the device class and the intended environment. A device intended for a domestic healthcare environment has tighter emissions limits than one intended for a professional healthcare facility, because domestic environments are near broadcast receivers and consumer electronics that are more sensitive to interference.

Immunity is the half that asks: how does your device behave when the environment pushes energy into it, and does that behaviour remain safe and effective? Immunity tests subject the device to a specified disturbance and then observe whether it still does what it is supposed to do. The disturbance types in EN 60601-1-2:2015+A1:2021 include radiated radio-frequency fields, conducted disturbances induced by radio-frequency fields, electrostatic discharge, electrical fast transients and bursts, surges, voltage dips and interruptions, and power-frequency magnetic fields. Each test represents a category of real-world electromagnetic insult — a mobile phone, a nurse's synthetic uniform building up charge, a nearby motor switching on, a power glitch during a thunderstorm.

Both halves matter. A device that passes emissions but fails immunity is unsafe. A device that passes immunity but fails emissions is a nuisance — and under the Regulation, a nuisance that disturbs other medical equipment is also unsafe. A clean EMC file addresses both halves explicitly.

What EN 60601-1-2:2015+A1:2021 actually tests

The test plan under EN 60601-1-2:2015+A1:2021 has four elements that have to be in place before the first plug goes into the wall at the test lab.

First, the essential performance of the device must be documented. Essential performance is the performance of a clinical function, other than that related to basic safety, where loss or degradation beyond specified limits would result in unacceptable risk. EN 60601-1-2:2015+A1:2021 uses essential performance as the yardstick for immunity acceptance criteria. No documented essential performance means the test lab cannot decide whether the device passed or failed — they have no definition of what "still working" means. This is the single most common reason a test campaign stalls before the first test is even run.

Second, the intended environment must be classified. The standard distinguishes between professional healthcare facility environments, home healthcare environments, and special environments. The immunity test levels and the emissions limits both depend on this classification. If your device is intended to go home with the patient, the test levels for immunity are higher — because home environments contain more uncontrolled electromagnetic sources.

Third, the configuration under test must reflect the worst case realistic configuration of the device as placed on the market. That includes cables of the maximum length stated in the instructions for use, the worst case orientation for the weakest mode, and all intended accessories. Test labs will not invent this configuration for you.

Fourth, the acceptance criteria must be tied back to basic safety and essential performance for each immunity test. "No change in indication" is a valid criterion for some devices. "Recovery within 10 seconds with user notification" may be valid for others. "Loss of alarm function for 200 milliseconds" is almost never valid because it crosses a basic safety line. The acceptance criteria are written by the manufacturer before the test, in the test plan, and are defended against the risk management file.

With those four elements in place, the test lab runs the emissions measurements and the immunity exposures defined by the standard, records the results, and issues a report. The report feeds into the technical file as evidence against the MDR Annex I provisions listed above. That mapping — which test addresses which MDR requirement — is what the Notified Body reviewer will be looking for.

Designing for EMC from the start versus chasing it at the test lab

Here is the pattern that produces the ugliest startup budget variances in this category. A team builds a prototype that works on the bench. They plan EMC testing as the final pre-submission step. They book the test lab. They show up. The device fails radiated immunity at 1 GHz because the enclosure has a seam that behaves like a slot antenna. They go home, redesign the enclosure, pay for new tooling, come back. The second visit reveals conducted emissions above the Class B limit because the power supply has no mains filter on the input. They redesign the power entry, come back. The third visit reveals an ESD sensitivity on the user interface button because the PCB ground plane was interrupted. They redesign the PCB, come back. Three visits. Three tool changes. Three accredited-lab bookings. Six to nine months. A six-figure variance against the original budget.

Every item on that list is preventable at the schematic and mechanical design stage. Shielding strategy, ground plane continuity, power entry filtering, cable shielding, connector choice, enclosure seam treatment, PCB stack-up, sensitive-trace layout, firmware-level tolerance to transient errors — all of these are EMC design decisions, not EMC test decisions. Teams that decide these things with 60601-1-2 in mind at Pass 2 of the Subtract to Ship framework typically pass the first formal test visit cleanly. Teams that decide these things based on "we will fix it at the lab" typically do not.

The practical sequence we recommend is: open the risk management file first, define basic safety and essential performance, identify EN 60601-1-2:2015+A1:2021 as the applicable EMC standard, walk the preliminary design against the four pillars of EMC design (shielding, filtering, grounding, firmware robustness), run pre-compliance testing at a cheaper facility, fix what the pre-compliance exposes, and only then book the accredited lab. The extra work at the start is smaller than a single re-test in the middle.

Common EMC test failures and what they tell you

A short list of failure patterns we see repeatedly in Notified Body interactions and test lab reports.

  • Radiated emissions above the limit around a clock harmonic. The board design placed the clock trace near an unshielded opening in the enclosure, or the clock oscillator has no spread-spectrum option and no damping resistor.
  • Conducted emissions above the limit on the mains. There is no input filter on the power entry, or the filter is there but the grounding is broken by an insulating paint layer under the mounting screw.
  • Radiated immunity failure at a cellular band. The device firmware has no recovery path from a transient signal-integrity glitch, and an input pin latches in an unexpected state. Fixing this can be a firmware change, a trace-level filter, or both.
  • ESD failure on a user interface surface. The enclosure has an exposed metallic trim that couples directly to a sensitive trace because the ground return was not designed for static discharge paths.
  • Electrical fast transient / burst failure on a signal cable. The cable is long, unshielded, and terminates on an unprotected input.
  • No essential performance defined. The test campaign stops before it starts because no pass/fail criterion exists for immunity. This is a documentation failure, not a hardware failure.

Every single one of these is cheaper to prevent than to debug after the fact.

Cost and timeline reality

A clean first-pass EMC test for a small Class IIa medical electrical device with a sensible pre-compliance history, in a professional healthcare environment, applying EN 60601-1-2:2015+A1:2021, sits in a very different cost bracket from a messy multi-iteration campaign. The clean case is a matter of a single accredited-lab booking of a few days, a single report, and a predictable contribution to the technical file. The messy case is multiple lab bookings, multiple tool revisions, multiple PCB spins, and a timeline that can add half a year to the certification project.

The cost driver is not the lab day rate. The cost driver is the number of iterations and the depth of the rework each iteration forces. A single PCB re-spin plus new tooling dwarfs the cost of a pre-compliance campaign that would have caught the problem in week one.

The Subtract to Ship angle — design-for-EMC-early

EMC is where the additive instinct looks most reasonable and is most expensive. Every team is tempted to overscope the immunity levels "just to be safe," to over-specify cable shielding "just to be safe," to over-engineer the enclosure shielding "just to be safe." None of those additions are free, and not all of them are needed for the intended environment.

The Subtract to Ship move is not to skimp on EMC. It is to match EMC scope precisely to the intended environment and the applicable collateral, and then to put the saved engineering budget into getting the few things that do apply right at the schematic stage. Test to the professional healthcare environment if that is the intended use. Do not test to the home healthcare environment if the device will never leave the hospital. Do not apply immunity levels from a standard that does not apply to your device. And do spend the week up front walking the design with EMC in mind — because that week pays for itself ten times over against the cost of one rework iteration.

The obligation is the MDR. EN 60601-1-2:2015+A1:2021 is the efficient route to proving you meet it. Both sentences matter, and the direction between them matters more than either in isolation.

Reality Check — Where do you stand?

  1. Have you documented essential performance for your device in writing, specific enough that a test lab could verify it?
  2. Have you classified the intended environment (professional healthcare, home healthcare, or special) and written down the classification?
  3. Have you walked the schematic against the four EMC design pillars — shielding, filtering, grounding, firmware robustness — before tape-out?
  4. Is EN 60601-1-2:2015+A1:2021 named explicitly in your standards list, alongside the general standard EN 60601-1:2006+A1+A12+A2+A13:2024?
  5. Have you planned a pre-compliance EMC pass before the first accredited lab booking, or are you planning to use the accredited lab as your debug bench?
  6. For each immunity test in the standard, do you know what "pass" means for your device in terms of basic safety and essential performance?
  7. Have you mapped your EMC test report back to MDR Annex I Section 14.2(d) and Section 17.1 in the technical file?

Frequently Asked Questions

Is EMC testing legally required by the MDR? The MDR does not name EMC testing as mandatory. What it requires, in Annex I Section 14.2(d) and Section 17.1, is that the device resists electromagnetic disturbances and performs reliably in its intended environment. EN 60601-1-2:2015+A1:2021 is the harmonised collateral standard that gives presumption of conformity with those obligations for medical electrical equipment. In practice, for any device with electronics, no realistic alternative route exists and every Notified Body expects this standard to be applied. So in effect, yes.

Can I use EN 60601-1-2 without also applying EN 60601-1? No. EN 60601-1-2:2015+A1:2021 is a collateral standard. It is always applied on top of the general standard EN 60601-1:2006+A1+A12+A2+A13:2024, not instead of it. The collateral modifies and extends the general standard on the topic of EMC and cannot stand alone.

Does EMC apply to battery-powered devices that never plug into the mains? Yes. Emissions limits and immunity requirements apply regardless of power source. A battery-powered device still radiates, still conducts through any cable connections, and still has to survive ESD, radiated RF fields, and magnetic fields in its intended environment. Some specific tests (mains conducted emissions, voltage dips and interruptions) do not apply if there is no mains connection, but the rest of the test plan does.

What is the difference between emissions and immunity? Emissions is what the device puts out into the environment — radiated or conducted. Immunity is how the device behaves when the environment pushes disturbances into it. Both must be addressed for any device with electronics, because both correspond to real safety obligations under Annex I.

Can pre-compliance testing replace accredited lab testing? No. Pre-compliance testing finds the large failures cheaply so the accredited lab visit is not used as a debug bench. The accredited test report from an ISO/IEC 17025 accredited lab is the evidence that enters the technical file. Pre-compliance is the cheap rehearsal; the accredited lab is the performance that counts.

What happens to the EMC evidence if the firmware changes after testing? It depends on whether the change affects basic safety, essential performance, or the specific behaviours the immunity tests exercised. A firmware change that alters alarm logic, recovery behaviour, or signal processing in the presence of noise will typically require at least partial retesting. The change control process in the QMS, driven by the risk management file, is what determines this.

Sources

  1. Regulation (EU) 2017/745 of the European Parliament and of the Council of 5 April 2017 on medical devices, Annex I Chapter II, Section 14 (construction of devices and interaction with their environment), in particular Section 14.2(d) (resistance to electromagnetic disturbances), and Section 17.1 (reliability of electronic programmable systems in their intended environment). Official Journal L 117, 5.5.2017.
  2. EN 60601-1-2:2015+A1:2021 — Medical electrical equipment — Part 1-2: General requirements for basic safety and essential performance — Collateral Standard: Electromagnetic disturbances — Requirements and tests.
  3. EN 60601-1:2006+A1+A12+A2+A13:2024 — Medical electrical equipment — Part 1: General requirements for basic safety and essential performance.

This post is part of the Electrical Safety & Systems Engineering Under MDR series in the Subtract to Ship: MDR blog. Authored by Felix Lenhard and Tibor Zechmeister. The MDR is the North Star. EN 60601-1-2:2015+A1:2021 is a harmonised tool that gets you there — useful, powerful, and only ever in service of the Regulation itself.