National Safety Authority (NSA)
A National Safety Authority (NSA) is the body each EU Member State designates under the Railway Safety Directive (EU) 2016/798 to regulate and supervise railway safety on its territory. Examples include the Eisenbahn-Bundesamt in Germany, EPSF in France and Trafikstyrelsen in Denmark.
The NSA supervises railway undertakings and infrastructure managers, enforces national safety rules, maintains national vehicle registers and monitors whether safety management systems work in practice. Each NSA publishes an annual report on its activities and sends it to the European Union Agency for Railways by 30 September.
The NSA’s role changed with the technical pillar of the 4th Railway Package. Since June 2019, the EU agency issues single safety certificates and vehicle authorisations for cross-border operations, with NSAs assessing the national parts; for operations limited to one Member State, the applicant chooses between the agency and the NSA.
Supervisor, not investigator
The NSA is a permanent supervisory authority, not an accident investigator. Independent investigation of serious accidents belongs to each country’s Accident Investigation Body (AIB), which operates separately from the NSA precisely so that findings are not shaped by the body that approved the operations under investigation.
The division of labour matters for how the system corrects itself. The NSA acts before and during operations — certification, authorisation, supervision — while the AIB acts after failures, and its safety recommendations feed back to the NSA for enforcement.
Without NSAs, EU rail safety law would have no national enforcement arm: directives and common safety methods only bind operators in practice because a designated authority supervises compliance on each network.