Abstract
Vibration of the seat and the body of a diesel locomotive and an electric locomotive were measured while driving on the railways of Eastern Finland. At the speed of 120 km/h for the diesel locomotive and 140 km/h for the electric locomotive (the greatest permissible speeds) the vibration of the seat was tangent to the “fatigue-decreased proficiency boundary” of the international standard ISO 2631/1(1) in the side-to-side direction in one-third octave bands of 1–1.6 Hz. The frequency response measurements between the body of the locomotive and the seat indicated that the seat did not reduce side-to-side vibration of the body at low frequencies where the vibration was most harmful.