Software tool certification for functional safety projects

About software development tool certification

When developing safety systems software, tools become more and more important. But it needs to be ensured that the software tool used in development complies with predefined criteria. The requirements of the software tools qualification employed in a functional safety development project therefore is often of big concern to many industry stakeholders like OEMs, system integrators, equipment manufacturers or tool vendors.

Often, a lot of open-ended questions are asked, which leads to long discussions during a project lifecycle, which can cause costly delays. In certification projects, this topic is often seen as an area of risk and uncertainty as more and more certified tools are available, but it’s not always clear which tool would lead to the highest benefit in the development project.

Tool certification is therefore used for development in safety-related environments such as in the automotive, automation, railway, medical or nuclear sector.

To reach a defined safety goal, it’s important to choose the right software tool right from the beginning of the safety-related development. Depending on the project needs, the required tools are planned based on the requirement from the safety standards and the related safety levels (ASIL, SIL, etc.).

But what have all the standards got in common? Only tools that can be trusted or which demonstrate that they do not create any undetected impact on the safety development can be used.

The level of trustiness required by the tool is named in a different way, depending on the standard. The most well-known is the Tool Confidence Level (TCL) used in the automotive domain. The analysis and determination of the TCL needs to consider the impact the tool has on the development process and possible failures that could occur. To avoid failures in the project, a profound tool assessment is needed to avoid any safety errors in the final system.

Tool assessment and certification provide various benefits in functional safety projects:

• Through the tool certification, tool vendors can claim fulfillment of the safety-related requirements by independent certification.
• The certification process ensures that all the relevant standards are covered at once, including:
  • IEC 61508,
  • ISO 26262,
  • EN 50128,
  • ISO 25119,
  • IEC 62304, and
  • IEC 60880.
• Failures and loss of trust can be avoided though the usage of a certified tool.
• The certification process can be tailored based on the complexity and individual requirements of the tool.

The certification process is also planned to cover the upcoming IEC 61508 Edition 3 requirements.

TÜV SÜD ensures safe software tools for your functional safety projects

TÜV SÜD offers proven capabilities backed by international recognition and understands the complex requirements in the field of functional safety. TÜV SÜD has been performing certification of software tools for over 10 years, which was initially based on the automotive requirements. Over the years, the number of certified tools has increased dramatically, covering the other industrial domains, too. For an overview of the certified tool, please refer to our central database. Having worked with several software’s already, you can rely on our experience and assessment approaches to identify the right and safe software tool for your functional safety projects. We support you with our assessment and testing services from the onset of your project with technical expertise that will result in a safe and reliable product. TÜV SÜD’s tool certification allows the usage of tools in safety-related projects in order to improve efficiency but maintaining the required level of safety. TÜV SÜD is involved in the standardization committee, which is continuously working on updating the requirements related to tools in safety-related projects, providing state-of-the-art interpretation of functional safety to customers.

TÜV SÜD’s software tool certification services

We offer two options for certification of tools:

OPTION 1: Functional Safety Mark for software tool certification (all standards)

The certification is based on the assessment of two aspects:

• Evaluation of the tool development process: An on-site audit is conducted based on a standard checklist. The requirements of the standard checklist are derived from the ISO 26262 and IEC 61508 standard requirements for software development. The duration of the audit is dependent on the complexity of the processes and tools.
• Evaluation of validation (test): Review of validation evidence for each provided functionality (feature tests, regression tests, etc.). The review is based on offline documentation review with focus on test documentation related to the tool use case/requirements.

Additional aspects are also considered during the assessment, such as:

• Defect management
• Customer interface
• Bug tracking interface, etc.
• Safety manual

This generic tool assessment approach allows the customer to claim suitability of the tool for the identified use cases in safety-related developments according to ISO 26262, IEC 61508, EN 50128, IEC 62304, etc. for any (A)SIL level or class.

OPTION 2: Tool Classification Level (TCL) 1 safety documentation certification (only applicable for ISO 26262)

The TLC 1 approach is an agile assessment consisting of a detailed review of tool safety documentation (safety analysis of tool impact and tool detection measures).
The assessment will prove that the tool manufacturer has provided adequate safety-related support documentation in order to claim TCL1 for the identified use cases, i.e. either demonstrating no Tool Impact (TI), or providing Tool Detection measures (TD) with a high degree of confidence.

Assessment of modifications for a newer version (re-certification) is also part of the certification (for both options). The re-certification follows a so-called “delta approach”, which is also able to match development processes of the tool based on iterative methods (like agile, etc.).

Additional Services

If you need help setting up the strategy for tool certification or tool usage in a safety-related project, we can also support you with these dedicated services:

• Gap analysis for tool qualification services
• Cooperation with external partner to perform tool qualification

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