How to Start with the IEC 62304 Standard Implementation

Quick Summary at the Beginning

For those who don’t want to read the entire article, here’s a quick summary:

• To buy the IEC 62304 standard at the best price, visit evs.ee .
• Don’t be intimidated by the IEC 62304 standard; get it and read it in its original form.
• Don’t skip Chapter 3: “Terms and Definitions.”
• The applicable parts of the standard depend on the software safety class of your product.
• Skip most of the introduction and focus on Chapters 5, 6, 7, 8, and 9.
• Pay special attention to Annex B, particularly:
  • B.1.1 - Possible approaches to software development, including Agile development.
  • B.5 - Practical guidelines for software architecture and software design.
  • B.6 - Software maintenance process.
  • B.8 - Configuration management.
  • B.9 - Software problem resolution.

My First Encounter with IEC 62304

When I first read the IEC 62304 standard, many of its requirements were difficult to grasp. Even when I understood them, I wasn’t sure how to apply them in practice. My understanding evolved over time as I went through audits, gathered insights from regulators through their feedback, and learned from findings in internal audits of partner companies.

I want to share my insights with you because practical advice is always valuable. This article is the first in a comprehensive series covering all chapters of IEC 62304. It provides practical recommendations that I wish I had known from the start, as they would have saved me a lot of time and effort.

Where to Get IEC 62304 for the Best Price

For our company, QMLogic, I purchase standards exclusively through the Estonian Center for Standardization and Accreditation (evs.ee ). They offer many standards at much better prices than ISO.org, and the English version you buy there is identical to the official release.

I recommend purchasing a multi-user license, which can then be opened as a standard PDF without the need to use a special program from the EVS organization.

Understand the Norm Even If You Are Not in the QMS Department

It might sound obvious, but don’t overlook this advice. The IEC 62304 standard isn’t just for quality managers or regulatory affairs specialists. It’s equally relevant for software engineers and engineering managers. By reading the standard in its original form, you’ll be better equipped to analyze different interpretations during discussions with team members, auditors, or external consultants. Understanding the standard provides a strong foundation for compliance and implementation.

Read the Original Standard, Not Just Online Interpretations

When it comes to ISO and IEC standards, FDA guidance, and many regulations, opinions vary. If you want to form your own perspective, you need to confront the original text, not just rely on interpretations from colleagues, consultants, or online articles.

It might be challenging at first, but with time, you’ll become familiar with the terminology and be able to quickly extract key requirements. Additionally, you’ll notice that related standards like IEC 81001-5-1 or IEC 82304 often overlap, describing similar concepts from slightly different angles.

Don’t Skip the “Terms and Definitions” Chapter

Many people skip Chapter 3: “Terms and Definitions”, but that’s a big mistake. If you don’t fully understand the terminology, working with the rest of the standard will be much harder.

To deepen your understanding, I recommend comparing definitions with other online resources and AI tools like ChatGPT or Claude. However, don’t settle for a single interpretation; challenge multiple sources to get a well-rounded view.

Key terms to focus on:

• Anomaly
• Configuration Item
• Software Development Life Cycle Model (spoiler: development doesn’t start with coding but with planning, and it doesn’t end with market release but with product withdrawal)
• Software Item
• Software Unit (don’t worry too much about the difference between item and unit for now; we’ll cover it in upcoming articles)
• Verification (spoiler: verification is not just testing!)

Consider Software Safety Class Under Each Paragraph

The concept of Software Safety Class deserves its own article, but for now, here’s what you need to know:

• Class A - Software errors cannot harm the patient.
• Class B - Software errors could cause harm.
• Class C - Software errors could cause serious harm.

Check Chapter 4.3 in IEC 62304 for more details.

Each paragraph from Chapter 5 onward specifies the software safety classes for which it applies. For example:

• [Class A, B, C] - The requirement applies to all software types.
• [Class C] - The requirement only applies to Class C software.

A great summary of these requirements can be found in Table A.1: “Summary of Requirements by Software Safety Class” in Annex A at the end of the standard.

Check the Release Date of Your IEC 62304 Standard

IEC 62304 was first published in 2006, but a significant 2015 amendment introduced changes, including updates to safety class applicability. If you purchase the consolidated version (IEC 62304:2015), you get the latest official version with all amendments.

Key IEC 62304 Requirements Are in Chapters 5-9

Unless you need to deep-dive into specific areas, you can skip the introductory chapters, except for:

• Chapter 3: “Terms and Definitions”
• Chapter 4.3: “Software Safety Class”

Focus on:

• Chapter 5 - Software Development Process
• Chapter 6 - Software Maintenance Process
• Chapter 7 - Software Risk Management
• Chapter 8 - Software Configuration Management
• Chapter 9 - Software Problem Resolution

These are the sections that auditors pay the most attention to.

The Most Valuable Information Is in Annex B

Although this tip appears at the end of the article, it’s crucial. I spent too much time jumping between Chapters 5-9 before I discovered Annex B at the back of the standard.

Annex B is not just an appendix; it makes up half the document and is titled “Guidance on the Provisions of This Standard.” While Chapters 5-9 tell you what to do, Annex B explains how to do it in practice.

Agile Development Is Allowed

Check Section B.1.1 to see that the IEC 62304 standard does not prohibit Agile development for medical device software. If someone tells you otherwise, they probably haven’t read this part.

Integration with Risk Management (ISO 14971)

Section B.4.3 provides a clear link between IEC 62304 and ISO 14971 (Risk Management for Medical Devices). This section helps clarify how to apply risk management to software architecture.

Other Interesting Chapters in Annex B

• B.5 - Explains every step of the software development process, including software architecture, detailed design, implementation, and verification.
• B.6 - Software Maintenance Process.
• B.8 - Configuration Management.
• B.9 - Software Problem Resolution.

If you find any errors or misinterpretations in this article, please let us know. Your feedback helps improve the understanding of IEC 62304 in the industry!