Freight vehicles for International traffic are registered in accordance with the regulations (RIV) of the UIC. Vehicles are scrutinised against the requirements of UIC fiches rather than Railway Group Standards. Once a vehicle has been shown to meet these technical requirements the Owner enters a contract for use with a Railway Undertaking (RU) who issues the final vehicle approval. In Great Britain the RU is EWSI.

Due to the specific nature of the British Network all foreign registered UIC vehicles must also be validated against specific requirements contained within fiche UIC503 before they are permitted to run within Great Britain.

EWSI ensure the vehicles are technically validated against UIC503 and that operational (including route acceptance) and legislative requirements are met. EWSI can then agree for the vehicles to be used on the British Network.

RAL is authorised by EWSI to perform technical evaluation leading to acceptance of wagons against both the RIV and UIC503. RAL is also authorised by RSSB to issue the required Engineering Acceptance certification.