Functional Safety Assessment according to ISO 61508 and EN 50126 for a TIER1 supplier in the railway industry

This image shows INVENSITY‘s Head of Safety Management, Philipp Hofmann. The title of the blog post is Functional Safety Assessment according to ISO 61508 and EN 50126 for a TIER1 supplier in the railway industry.

May 7, 2024 – Reading time: 4 minutes

With the increasing automation of passenger and freight transportation, the complexity of railroad development is also increasing. This leads to ever higher demands on functional safety, which ensures that safety risks to life and limb are kept as low as possible by the railroad system. However, it is precisely this increase in requirements, which are generally defined by legislators and rail operators, that is becoming a challenge for both original equipment manufacturers (OEMs) and their suppliers.

Standards such as EN 50126 (RAMS), EN 50128 and EN 50129 are used as benchmarks, compliance with which must be proven for product approval. At this point, it is essential to possess not only a thorough grasp of the standards and the system but also the capability to integrate safety into product development. Both as a starting point for safety-compliant development and as proof of compliance with the standards to clients or for your own quality assurance, as well as in preparation for a required safety audit, the implementation of a safety assessment by a neutral party is a good idea. We have carried out such an assessment for one of our customers, a leading TIER1 supplier in the rail industry.

A safety assessment is a standardized, proven procedure that can be carried out at short notice to compare the current state of development with the requirements of the relevant standards at both product and process level. Such an assessment can be carried out in-house, i.e. by the company’s own safety managers, or outsourced to an external third party. External outsourcing is usually recommended when resource bottlenecks, whether they are of a personnel nature or related to newly acquired expertise, need to be overcome quickly.

At INVENSITY, we are able to complete such an assessment within two weeks. Customers then receive a gap list. This shows which gaps still need to be closed in order to meet the requirements of the relevant standard. We also provide a very specific action plan that explains how these gaps can be closed operationally.

Both the speed and the development of specific and action-oriented solutions convinced our customer. In this very specific case, their quality management stipulated that an internal safety assessment should be carried out at certain milestones, based on ISO 61508 (System Safety) and EN 50126 (RAMS). The customer installed this regular and systematic survey in order to be able to ensure that the requirements set by the client for product freedom were met.

Thanks to our many years of expertise in the safety sector and our experience in preparing for TÜV audits, we were able to carry out a complete analysis of all safety-relevant activities and documents for the customer’s complex system within a very short time. Thanks to good and active cooperation with our contact person at the customer, the Project Safety Manager, open questions were quickly addressed and clarified. Among other things, we checked whether all the necessary documents were available and whether they contained the required information. Our team also examined whether the processes of the safety life cycle had been adhered to and whether the safety measures and the associated reasoning were comprehensible. It was then necessary to evaluate whether the implementation of the risk reduction could be verifiably documented.

The gap analysis made it possible to efficiently identify security gaps and derive a plan with specific recommendations for action. This was discussed with the customer. One of the gaps identified concerned a document required by the process that was not created during development. However, the Safety Manager was able to show that the contents required by the standard were fully included in the Safety Management Plan (SMP). The process deviation was discussed internally, approved and subsequently documented in the SMP. A final assessment report, combined with further recommendations, confirmed to the customer that the process and the safety standards were sufficiently fulfilled and that the system met the internal quality requirements.

In order to avoid safety gaps in the future, to be better prepared for audits and to empower employees in the area of functional safety, we carried out additional training courses on safety-compliant work in accordance with ISO 61508 and EN 50126 and on establishing a safety culture on site after consulting with the customer.

If you are interested in a functional safety assessment in the future or need support in preparing for an audit, please contact us for a non-binding consultation.


  • Faissal Makrini

    Technology Consultant

Contact Person

  • Philipp Hofmann

    Head of Safety Management

How can we accelerate your development?
Let’s start


Learn more