Medical Device Usability Requirements in South Korea — Legal Basis and How to Prepare

Key takeaway — Usability in Korean medical device review asks not "is it easy to use" but "did the design control the ways it can be used wrongly." The Korean legal basis is the Common Standards for Electrical and Mechanical Safety of Medical Devices (MFDS Notice No. 2025-40, in force since June 17, 2025): among devices using electrical or electronic circuits, those for which usability needs to be established are additionally subject to [Annex 3], the supplementary usability standard (Article 3(1)). The international reference is IEC 62366-1, and the output only carries weight when it connects to the risk management file. Verified as of August 2026.

"Nice to use" and "usability" are different questions

Usability review runs in the opposite direction from marketing. Marketing asks how pleasant the device is; review asks how it can be used wrongly, what happens then, and whether the design prevents it. Two buttons confusable enough to set the wrong dose, an alarm muted and never restored, a home-use device operated without reading the manual — these use errors are the object of analysis.

That is why the backbone of a usability file is not one usability test report but a record of a process: defining the intended user (professional or lay), the use environment (hospital or home), identifying hazardous use scenarios, controlling them through interface design, and confirming by evaluation. The international standard that defines this methodology is IEC 62366-1.

The Korean basis — Article 3 and Annex 3 of the common standards

In Korea, this requirement attaches through the Common Standards for Electrical and Mechanical Safety of Medical Devices (MFDS Notice No. 2025-40, in force June 17, 2025).

• Scope: instruments, machines, and apparatus using electrical or electronic circuits (Article 2)
• Additional-application structure: Annex 1 (common standards and test methods) applies as the baseline, and devices for which usability needs to be established are additionally subject to [Annex 3], the supplementary standard on medical device usability (Article 3(1) subparagraph 2)
• The same structure gives radiation-emitting devices Annex 2, alarm-signal devices Annex 4, and physiological closed-loop controller devices Annex 5

The practical implication is clear: whether your product is in scope is the first question, and the answer comes from Annex 3 and the product-specific standard, not from guessing. Within the framework of how test standards are selected, usability is best understood as one more axis that attaches on top.

Unconnected to risk management, the file floats

The starting point of usability analysis — hazardous use error — is a hazard in risk management terms. If a use scenario exists in the usability file but not in the risk management file, or vice versa, the consistency question follows immediately. By the same principle that makes specification–report–labeling agreement the heart of the technical file, usability ↔ risk management ↔ instructions and warnings (IFU) must agree.

Warnings deserve a special note: from a usability standpoint, a warning is the last resort. Handling an error that design could prevent with a caution sentence alone invites the reviewer to re-ask the hierarchy of controls.

How to prepare — three steps

Step 1 — Confirm scope. Check the product-specific standard and Annex 3 of the common standards for whether usability applies. Everything downstream depends on this call.

Step 2 — Define users, environments, and error scenarios. Specify the intended user and environment in writing, and identify hazardous use errors in the same language as the risk management file. For home-use and lay-user devices, the density of this step drives review difficulty.

Step 3 — Design controls and evaluation records. Control the errors through the interface — screens, buttons, labels, IFU — and keep the evaluation records. If the overseas manufacturer already holds IEC 62366-1-based files, that is your starting asset — but as always with foreign documentation, the first step is a gap check against Korean format requirements, not submission as-is.

Common mistakes

• Writing the usability file retroactively after development — as a process record, the chain has gaps and deficiencies follow
• Use error scenarios that live apart from the risk management file
• Controlling design-preventable errors with warning sentences only
• Marketing a professionally designed device for home use without updating the user definition

Checklist before you proceed

• Check the product standard and Annex 3 for usability applicability
• Document the intended user and use environment
• Cross-check hazardous use scenarios against the risk management file
• For imports, confirm whether the manufacturer holds IEC 62366-1-based files and in what form
• Review whether IFU and labeling warnings duplicate or complement the design controls

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Usability is an area where cases diverge from the very first question of applicability. Send us the product name and the use environment (professional or home) and the free preliminary review will map the applicability check and the skeleton of the file to prepare.