UIC Leaflet 912-2: Standard Numerical Coding for Wagons

What is UIC Leaflet 912-2?

UIC Leaflet 912-2 is a foundational document for Information Technology in the rail industry, titled “Standard numerical coding of wagons.” In the context of Freight Traffic, millions of wagons cross international borders annually. To manage this at scale, every wagon must possess a globally unique and machine-verifiable “identity.”

This leaflet provides the technical rules for the 12-digit numbering system found on the side of every European freight wagon. It is a core component of Interoperability, enabling seamless Electronic Data Interchange (EDI) between different railway undertakings and infrastructure managers.

Structure of the 12-Digit Wagon Number

The 12-digit code defined in UIC 912-2 is not random; each segment provides specific technical or administrative information about the Rolling Stock:

• Digits 1–2 (Interoperability Code): Indicates the technical characteristics and the ability of the wagon to operate in international traffic (e.g., RIV/RIC status).
• Digits 3–4 (Country Code): Identifies the country where the wagon is registered (e.g., 80 for Germany, 70 for UK).
• Digits 5–8 (Technical Characteristics): Encodes the wagon type (Flat, Tank, Covered), the number of axles, and loading capacity.
• Digits 9–11 (Serial Number): A unique number within the specific wagon class.
• Digit 12 (Self-Check Digit): A mathematical digit used to verify that the previous 11 digits were entered or scanned correctly.

The Self-Check Digit (Luhn Algorithm)

To prevent data entry errors in Logistics Management, UIC 912-2 mandates the use of the “Luhn Algorithm” (modulus 10). This ensures that if a single digit is mistyped or misread by an OCR camera, the system will immediately flag the number as invalid.

The calculation involves multiplying the digits by a 2-1-2-1 pattern, summing the results, and determining the difference to the next multiple of ten. This simple but effective mechanism is vital for TAF TSI compliance.

Physical Application: Wagon Labeling

The leaflet also specifies the Wagon Labeling requirements:

• Visibility: The number must be applied in a high-contrast color (usually white on a dark background) on both longitudinal sides of the wagon.
• Font and Size: Specific height and width requirements for the characters to ensure they can be read by automated wayside cameras at high speeds.
• Letter Codes: The numerical code is often accompanied by letter codes (e.g., Eans, Shimmns) which provide a human-readable summary of the wagon’s technical features.

Structure of a UIC Wagon Number (Example: 31 80 0691 235-2)