Seat components and claddings for railway molded or formed from a thermoplastic polymer composition comprising, based on the total weight of the composition, 50 to 93 wt. % of a specific polycarbonate; 4 to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenol A carbonate units, and siloxane units; 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; wherein an article having a thickness of 0.5 to 10 mm molded from the composition has a Ds-4 smoke density≦300 measured according to ISO 5659-2, and a MAHRE≦90 kW/m2 measured according to ISO 5660-1, a multiaxial impact energy ≧100 J, and a ductility in multiaxial impact of 80 to 100% at +23° C. according to ISO 6603.