Interoperability for newly adopted countries in the EU is key to trains safety. Calculating the braking force used by the Leaflet 544-1 of the UIC Leaflet  brake elements is important for safety when running trains in the braking mode.
The researching of the facts shows that Regulation 58  is harmonized with the contents of UIC Leaflet 544-1 and EU Regulation No 1302/2014 . The test is to be used for the interoperability of the technical infrastructure in connection with Commission Regulation (EU) No 1299/2014 of 18 November 2014  on technical specifications for interoperability with respect to the infrastructure subsystem of the railway system in the Union concerned.
When designing the rail lines used braking calculation, made by easy way remain based on the friction of the pads on the wheel surface, but it is not related to the examples in the UIC Leaflet 544-1 .
- UIC Leaflet 544-1: Brakes - breaking performance
- Ordinance 58 of 2.08.2006 on the rules for the technical operation, movement of trains and signaling in railway transport, issued by the Minister of Transport, promulgated SG, issue 73 of 5.09.2006, amended, issue 88 from 2007, as amended. and suppl., issue 43 of 2009, issue 68 of 2014, and issue 97 of 23.11.2018, effective from 24.02.2019.
- Commission Regulation (EU) N1302/2014 COMMISSION REGULATION (EU) No 1302/2014 of 18 November 2014 concerning a technical specification for interoperability relating to the ‗rolling stock — locomotives and passenger rolling stock‘ subsystem of the rail system in the European Union, Official Journal of the European Union, L 356/228-393 http://data.europa.eu/eli/reg/2014/1302/oj
- Commission Regulation (EU) No 1299/2014 of 18 November 2014 on the technical specifications for interoperability relating to the ‗infrastructure‘ subsystem of the rail system in the European Union Text with EEA relevance http://data.europa.eu/eli/reg/2014/1299/oj
- DIN EN 14531-1:2005: Railway applications - Methods for calculation of stopping distances, slowing distances and immobilization braking - Part 1: General algorithms, May 2005,
- DIN EN 14531-6:2009: Railway applications - Methods for calculation of stopping and slowing distances and immobilization braking - Part 6: Step by step calculations for train set or single vehicles
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