EN 45545-2 controls the fire behaviour of materials in railway vehicles. Instead of one test, it defines requirement sets (the R-sets) matched to material use - interior surfaces, seats, cables, hoses and so on - and three hazard levels, HL1 to HL3, set by the vehicle's operation and design categories. The same material can pass for HL1 and fail for HL3, because the limits tighten with the level.
The tests inside the sets
Most interior sets combine the same instruments: oxygen index to ISO 4589-2 as a flammability floor; smoke density to ISO 5659-2 in the NBS chamber, reported as Ds and VOF4 values; smoke toxicity by FTIR analysis of the chamber gases, expressed as the CIT index under EN 17084-referenced methods; and, for floorings and some surfaces, heat release by cone calorimeter or radiant panel methods. Seat assemblies have their own furniture-scale route (see EN 16989 in our blog), and cables follow their own sets.
Planning a railway test programme
Start from the R-set for your component and the hazard level of the vehicle programme; the set names the tests and the limits. Our railway sector page maps the sets to the Motis instruments that run them - fire testing for railway applications - and the individual instruments (NBS chamber, oxygen index, FTIR) are in the product index.