IEC 62366 / HE75

IEC 62366-1:2015+AMD1:2020 specifies a usability engineering process for medical devices that allows manufacturers to identify, analyze, specify, design, verify, and validate aspects of a medical device's user interface that relate to safety.

The standard recognizes that use errors — mistakes made by trained, experienced users — are a leading cause of medical device adverse events. The usability engineering process is designed to proactively identify and mitigate use-related risks before they cause patient harm.

IEC 62366-1 is harmonized with the EU MDR (listed in Annex ZA), recognized by FDA as a consensus standard, and adopted by regulatory authorities in Canada, Japan, Australia, and worldwide.

Intended Use and User Profiles: Define the device's intended use, the intended user populations (lay users, healthcare professionals, operators), and the use environments.

Use-Related Risk Analysis (URRA): Systematically identify hazardous situations arising from use errors and evaluate their severity. The URRA feeds into ISO 14971 risk management and drives the selection of critical tasks.

Summative Usability Evaluation: The validation test demonstrating that representative users can safely and effectively use the device. The summative evaluation must test all critical tasks with a sufficient sample of representative users.

Usability Engineering File (UEF): The collection of records documenting the complete usability engineering process. The UEF must be maintained throughout the product lifecycle and is reviewed during regulatory submissions and audits.

Formative Evaluations: Iterative usability studies conducted during design development to identify and resolve use problems before the summative evaluation. While not strictly required by the standard, FDA guidance strongly encourages formative studies.

AAMI HE75:2009/(R)2018 provides detailed technical guidance on human factors engineering methods for medical devices — complementing the process requirements of IEC 62366-1 with specific techniques, example study designs, and worked examples.

Where IEC 62366-1 defines what to do (the process), AAMI HE75 explains how to do it well. Key HE75 topics include: user interface design principles, user research methods, task analysis techniques, and usability test design guidance.

FDA's HFE guidance documents frequently reference both IEC 62366-1 and AAMI HE75 in tandem. Medical device manufacturers targeting FDA clearance or approval should align to both documents, not just the ISO standard.

FDA's 2016 guidance 'Applying Human Factors and Usability Engineering to Medical Devices' establishes FDA expectations for HFE in premarket submissions — and goes beyond IEC 62366-1 in several important areas.

Key FDA-specific requirements include: critical task identification (with explicit justification for which tasks are and are not critical), use error analysis in the summative evaluation report, and HFE report submission (a standalone summary document required in most 510(k)s, De Novos, and PMAs).

FDA also provides specific guidance for complex device types: combination products, drug delivery devices, in vitro diagnostic devices, and software user interfaces each have additional FDA human factors expectations beyond the base standard.