The role of the competent technical body in the railway sector

The work of a competent technical body is based on defined standards and guidelines. The German Federal Railway Authority (EBA) has introduced DIN 27201-7 as a recognised technical rule within its area of responsibility. This makes the standard binding for all vehicles operating on routes under the EBA’s jurisdiction.

The guidelines of the German Society for Non-Destructive Testing (DGZfP) also apply:

• Guideline ISB1: requirements for a competent technical body in accordance with DIN 27201-7
• Guideline ISB2: procedure for the recognition of NDT testing facilities carrying out non-destructive testing in accordance with DIN 27201-7

DIN 27201-7 requires the involvement of a competent technical body when non-destructive testing (NDT) is carried out as part of the maintenance of safety-related components. These include, for example, wheelsets, axles and load-bearing structural components of rail vehicles.

Responsibilities of a competent technical body

The principal task of the competent technical body (known in German as a Fachlich zuständige Stelle, or FzS) is to assess and recognise workshops that carry out NDT during maintenance. This involves checking whether personnel, methods, testing techniques and documentation meet the requirements of the standards. Guideline ISB1 defines further tasks, including:

• Recognition of workshops for NDT during maintenance
• Approval and recognition of NDT inspection methods and testing techniques
• Preparation and approval of testing instructions
• Conducting damage investigations
• Approval and recognition of railway-specific reference blocks
• Contributing to the development of teaching content for training testing personnel in the railway sector

The FzS thus provides a technically independent quality assurance function between the maintenance organisation, testing facility and supervisory authority.

Requirements for an FzS

A competent technical body is recognised through the DGZfP’s Railway Technical Committee (FA Bahn), in coordination with the EBA. Under Guideline ISB1, an FzS must meet requirements including:

• Organisational independence from railway operations and maintenance
• Accreditation to EN ISO/IEC 17020 (inspection body) or EN ISO/IEC 17025 (testing laboratory)
• Engineering personnel with Level 3 NDT certification for the railway sector
• Many years of practical experience in railway maintenance
• Suitable technical equipment for all relevant NDT inspection methods

These requirements ensure that the FzS performs its duties competently, impartially and in accordance with the standards.

The recognition procedure for a competent technical body

The recognition of an FzS by the DGZfP and its Railway Technical Committee, in cooperation with the EBA, involves several stages:

• Submission of an application to the DGZfP’s Railway Technical Committee
• Appointment of an audit team
• An audit at the applicant organisation
• Presentation of the audit report to the technical committee
• A decision on recognition

Official recognition as a competent technical body is granted only after this procedure has been successfully completed.

Recognition of workshops under ISB2

The recognition of NDT testing processes in workshops is governed by Guideline ISB2. In simplified terms, the procedure comprises the following steps:

• An enquiry from the workshop and preparation of a quotation based on relevant information, including locations, inspection methods, components tested and personnel deployed
• An audit of the workshop focusing on documentation, technical equipment, personnel qualifications and the practical execution of testing
• Issue of the recognition certificate, where necessary following implementation of specified corrective actions
• Publication of the recognition in the DGZfP’s online register
• Regular surveillance audits to maintain the time-limited recognition

This ensures a continuous improvement process and long-term monitoring of compliance with the requirements of the standards.

Practice and outlook: the FzS in the railway sector

Since DIN 27201-7 applies to all maintained vehicles operating on routes under the EBA’s jurisdiction, the work of the competent technical body extends across numerous maintenance locations, including outside Germany.

The experience gained during these audits provides valuable insights into the practical implementation of NDT processes in railway maintenance. These findings will be discussed in a further article.

W.S. Werkstoff Service – expertise in the railway sector

By combining practical testing experience, expert assessment work and work on technical rules, we make an important contribution to the further development of inspection methods and technical standards in freight wagon maintenance. An overview of our services is available at https://www.werkstoff-service.de/en/w-s-railwaycenter/.