IEC 62366-1 and IEC 60601-1-6 Usability Engineering for Medical Devices

IEC 60601-1-6 is a collateral standard within the IEC 60601 series that focuses on usability engineering, the process of designing medical devices to minimize use-related risks and errors.

Within the IEC 60601 framework:

• IEC 60601-1 defines general safety and essential performance
• IEC 60601-1-6 focuses on usability and human interaction
• IEC 60601-2-XX standards define device-specific requirements

IEC 60601-1-6 is closely aligned with IEC 62366-1, which provides a detailed framework for usability engineering processes across medical devices.

IEC 60601-1-6 ensures your device can be used correctly, safely, and consistently by the people it was designed for.

IEC 62366-1 is the international standard that defines the usability engineering process for medical devices. It provides a lifecycle-based approach to identifying how users interact with a device, where errors may occur, and how design can reduce or eliminate those risks.

While standards like IEC 60601-1-6 apply usability principles within the medical electrical equipment framework, IEC 62366-1 operates at a broader level. It defines the process, documentation, and validation expectations that manufacturers must follow to demonstrate that use-related risks have been systematically addressed.

In practical terms, IEC 62366-1 ensures that usability is not treated as an afterthought or a subjective design exercise. Instead, it becomes a structured, evidence-based discipline that supports regulatory compliance and patient safety.

The two standards are closely aligned and are typically evaluated together as part of a complete usability engineering and compliance strategy.

Together, they help manufacturers ensure that medical devices are not only technically compliant, but also safe, intuitive, and effective for the people using them in real-world conditions.

All of these standards work together to create a more complete and defensible approach to medical device safety.

Many medical device risks are not caused by component failures or hardware defects. Instead, they emerge through user interaction.

Use-related risks may occur when:

• Controls are confusing or poorly labeled
• Interfaces are overly complex
• Workflows are difficult to follow
• Instructions are unclear or incomplete
• Devices are used under stress or time pressure
• Non-clinical users operate devices in home environments

Modern medical devices increasingly rely on touchscreen interfaces, software-driven workflows, connectivity, remote operation, and use by patients or caregivers outside traditional healthcare facilities. These factors increase the importance of usability engineering and human factors validation.

Regulators increasingly expect manufacturers to demonstrate that use-related risks have been systematically identified, evaluated, mitigated, and validated rather than simply assumed to be acceptable.

IEC 62366-1 and IEC 60601-1-6 define a structured usability engineering process that begins with understanding users and ends with validating safe device operation.

Manufacturers begin by identifying intended users, use environments, and critical tasks. From there, realistic use scenarios are developed to evaluate how users interact with the device in practice, not simply how the device was intended to function in theory.

The process then focuses on identifying hazard-related use scenarios where user interaction could lead to harm. Risk control measures are implemented to reduce or eliminate those risks, often through interface design improvements, workflow simplification, alarms, prompts, or other usability enhancements.

Finally, usability validation confirms that representative users can safely and effectively operate the device under expected conditions.

This process is grounded in real-world user behavior, including stress, fatigue, distractions, environmental conditions, and varying levels of training or experience.

Usability engineering is a critical component of a complete Risk Management File.

The RMF is intended to demonstrate how a device has been made safe throughout its lifecycle. That story is incomplete without addressing how users interact with the device and where use-related risks may occur.

IEC 62366-1 helps manufacturers identify risks that may not be captured through traditional engineering analysis alone, including:

• Confusing workflows
• Misinterpretation of information
• Improper operation under stress
• Incorrect setup or configuration
• Delayed response to alarms or prompts
• User actions that could result in hazardous situations

Within the RMF, usability engineering contributes:

• Hazard-related use scenario identification
• Use error analysis
• Design-based risk controls
• Usability validation evidence
• Traceability between risks, mitigations, and validation activities

This aligns closely with ISO 14971 expectations, where all reasonably foreseeable risks, including those related to human interaction, must be identified and controlled.

Usability engineering applies broadly to medical devices where user interaction can impact safety or essential performance. This includes everything from traditional hospital-based equipment and diagnostic systems to portable, mobile, and software-driven medical technologies that rely heavily on user interfaces and workflow interaction.

As healthcare delivery continues to evolve, usability considerations have become especially important for connected medical devices, wearable technologies, and home healthcare equipment used by patients and caregivers outside controlled clinical settings. Devices that incorporate touchscreen interfaces, remote connectivity, software-driven workflows, or real-time monitoring capabilities often introduce additional human factors considerations that must be evaluated as part of the overall safety and risk management strategy.

Whether the device is used by clinicians in fast-paced hospital environments or by non-clinical users at home, usability engineering helps ensure that the technology can be operated safely, effectively, and consistently under real-world conditions.

Even experienced development teams can face challenges when integrating usability engineering into product development and broader risk management activities. One of the most common difficulties is identifying realistic use scenarios that accurately reflect how devices will be operated in real-world environments rather than idealized conditions. Manufacturers must also anticipate how users may behave under stress, fatigue, time pressure, distractions, or varying levels of training and experience.

These challenges become even more significant as medical devices grow increasingly software-driven, connected, and interface-heavy. Complex workflows, touchscreen interfaces, remote functionality, and home healthcare use conditions can all introduce additional opportunities for use-related risk that may not emerge through traditional engineering analysis alone.

Many manufacturers also struggle with aligning usability engineering activities with ISO 14971 risk management expectations, integrating usability findings into the Risk Management File (RMF), and generating meaningful usability validation evidence that satisfies regulator expectations. In some cases, usability engineering is treated as a late-stage activity rather than an integrated part of product development, leading to gaps in documentation, additional regulatory scrutiny, costly redesigns, or delayed approvals.

Usability engineering is increasingly emphasized across global regulatory frameworks.

Key regulatory alignment includes:

• FDA Human Factors and Usability Engineering guidance
• EU MDR expectations for safe and effective use
• IEC 62366-1 usability engineering requirements
• IEC 60601-1-6 usability expectations within electrical safety evaluations
• ISO 14971 risk management integration

Regulators increasingly expect manufacturers to provide objective evidence that use-related risks have been systematically identified, mitigated, and validated through documented usability engineering activities.

Intertek helps manufacturers integrate usability engineering into a broader medical device compliance and risk management strategy. Our teams support usability engineering, human factors evaluations, usability validation, and RMF integration across a wide range of medical technologies, including connected devices, home healthcare systems, wearable technologies, and software-driven platforms.

We work with manufacturers to define intended users and use environments, identify hazard-related use scenarios, and align usability engineering activities with ISO 14971 risk management expectations. Our support extends across formative and summative evaluations, usability validation planning, and the development of regulator-ready documentation that connects usability findings directly to the broader Risk Management File.

Because usability engineering does not exist in isolation, Intertek also helps manufacturers align human factors activities with broader IEC 60601 compliance efforts and overall product safety strategies. With experience across complex medical technologies and evolving global regulatory expectations, Intertek provides practical guidance that helps manufacturers reduce risk, improve usability, and move forward with confidence.

Usability engineering is most effective when integrated early and continuously throughout product development.

Addressing usability late in development can lead to avoidable redesigns, validation failures, and regulatory delays. By incorporating usability engineering and human factors considerations from the beginning, manufacturers can improve device safety, streamline compliance activities, and strengthen regulatory submissions.