Training IEC 62304 SDLC training now available — structured learning, timed assessment & certificate

White Paper · Usability · AI

IEC TS 62366-3
Usability Engineering for AI-Enabled Medical Devices

A practical guide to the first Committee Draft · Version 2.0 · October 2026

IEC TS 62366-3 explains how to apply IEC 62366-1 to medical devices that use AI. Our white paper sets out what the draft says, how it fits with ISO 14971 and regulation, and how to build it into your existing usability process, with a fully worked example you can follow.

Summary Slides (PDF)
At a Glance
19 pages
By Niamh St John Lynch, St John Lynch & Co
90-day plan
To add an AI layer to your IEC 62366-1 process
7-step example
From use specification to post-market plan
9 methods
Complementary analysis methods, with trade-offs

AI Moves Use Error from the Hands to the Head

The draft adds no new mandatory requirements. It shows how each step of the IEC 62366-1 process adapts when the biggest dangers are cognitive: misreading a probability, trusting the AI too much or too little, or not knowing where it is weak. For manufacturers, that means five things.

1
Plan for the future workflow, not the current one
AI changes roles, tasks and use environments, so research methods have to look ahead rather than just observe today's practice.
2
Treat transparency and explainability as user interface design
What the AI tells users about its confidence, inputs and limits is a risk control, and it must be specified and tested.
3
Analyse both routes to harm
A use error can corrupt the AI's input (Path A), or a user can act wrongly on a correct or incorrect AI output, away from the device (Path B).
4
Keep usability evaluation separate from AI performance validation
Even when one study session covers both, keep separate objectives, protocols and reports.
5
Expect behaviour to drift after launch
Trust in AI tends to grow with experience, so post-market surveillance should look for automation bias as well as device faults.

Where AI-Related Use Errors Begin

Most AI-related use errors start at cognition, where outputs are interpreted and trusted. The resulting action either feeds bad input into the AI (Path A) or causes harm elsewhere (Path B). Path B is easy to miss because the harm happens outside the device being assessed.

Diagram: perception, cognition and action, with cognition highlighted, leading to Path A at the device and Path B away from the device

Built to Be Used, Not Just Read

Roadmap

From Draft to Procedure

A clause-by-clause map from IEC 62366-1 to what Part 3 adds for AI and the evidence to produce, with a 90-day plan and links to ISO 14971, IEC 62304, EU MDR, the EU AI Act and FDA.

Worked Example

An AI Sepsis Early-Warning System

A fictional device taken through seven steps: use specification, contributing factors, Path A and Path B hazards, a use scenario, testable UI requirements, evaluation and post-market plan.

Beyond the Draft

Generative AI, Agents & Beyond PCA

Use errors and design patterns for generative AI and AI agents, and how STPA and situation awareness find risks that a single-user analysis can miss.

The Summary in Eight Slides

The key points, figure and worked example as a short slide deck. Free to view and easy to share with your team.

Title slide of the IEC TS 62366-3 white paper summary deck

Get the Full White Paper

All 19 pages, including the worked example, the complementary methods and the full references.