Specific case

A specific case is a provision written into a TSI that allows a member state, network or defined class of situations to deviate from the TSI's general requirement — permanently ('P' cases) or temporarily ('T' cases) while migration completes. Specific cases exist because Europe's railways were built to different gauges, electrification systems, clearance profiles and operating rules, and the TSIs regulate the transition to a common target rather than pretending the differences away: the Iberian 1668 mm gauge, the Nordic loading gauge, or particular platform heights all survive as specific cases. For anyone applying a TSI the practical consequence is that the general requirement is not the whole story — the specific-case annex must be checked for each member state in scope, and where a specific case applies, the requirement it modifies is typically covered by notified national rules assessed by a Designated Body rather than a Notified Body. ERA's application guides list the specific cases per TSI and per state.