Effects of vibration on sedentary activities in passenger trains

The effects of vibration on train passengers' sedentary activities were investigated with a questionnaire survey as well as onboard vibration measurements. Three types of Swedish inter-regional trains were studied on four different lines. 330 passengers were randomly selected for the questionnaire survey. The vibration measurements were made at five positions around a passenger seat above the bogie during normal service. The vibration data were weighted according to ISO 2631-1 and the older German (Sperling) Ride Index Wz. Two-thirds of the passengers reported difficulties in performing sedentary activities such as reading and writing due to vibration and shocks. However, the standardized measurements did not reveal any severe discomfort values due to the vibration. This reveals that ISO and Wz standards do not evaluate vibrations effect on sedentary activities correctly. This also indicates that even low levels of vibration can reduce the ability to perform sedentary activities. Both chair and table produced more vibration than the floor. The spectral analysis showed that the chair had nearly the same frequency content as the floor, below 10 Hz. This range is critical since it coincides with the most vulnerable range for reading and writing as well as the perception of ride comfort.