Passenger comfort on high-speed trains: effect of tunnel noise on the subjective assessment of pressure variations

Abstract

When passing through a tunnel, aerodynamic effects on high-speed trains may impair passenger comfort. These variations in atmospheric pressure are accompanied by transient increases in sound pressure level. To date, it is unclear whether the latter influences the perceived discomfort associated with the variations in atmospheric pressure. In a pressure chamber of the DLR-Institute of Aerospace Medicine, 71 participants (M = 28.3 years ± 8.1 SD) rated randomised pressure changes during two conditions according to a crossover design. The pressure changes were presented together with tunnel noise such that the sound pressure level was transiently elevated by either +6 dB (low noise condition) or +12 dB (high noise condition) above background noise level (65 dB(A)). Data were combined with those of a recent study, in which identical pressure changes were presented without tunnel noise (Schwanitz et al., 2013, 'Pressure Variations on a Train - Where is the Threshold to Railway Passenger Discomfort?' Applied Ergonomics 44 (2): 200-209). Exposure-response relationships for the combined data set comprising all three noise conditions show that pressure discomfort increases with the magnitude and speed of the pressure changes but decreases with increasing tunnel noise. Practitioner Summary: In a pressure chamber, we systematically examined how pressure discomfort, as it may be experienced by railway passengers, is affected by the presence of tunnel noise during pressure changes. It is shown that across three conditions (no noise, low noise (+6 dB), high noise (+12 dB)) pressure discomfort decreases with increasing tunnel noise.

Definition of an On-Board Comfort Index (Rail) for the Railway Transport

“…A further study [16] investigates the influence of tunnels on comfort on high-speed trains, simulating, in a pressure chamber, the only acoustic discomfort due to the crossing of railway tunnels. The study demonstrates using a scale from 0 to 6, as the lowest discomfort was obtained for the condition with the highest increase in sound pressure level (+12 dB noise tunnel).…”

Investigation on Passenger Comfort During HST Operation Using a New App for Smartphones

“…In order to clearly quantify the passenger's sense of pressure discomfort, the discomfort feeling is divided into seven levels (i.e., 0 'not at all', 1 'slightly', 2 'moderately', 3 'fairly', 4 'very', 5 'awfully', and 6 'extremely' uncomfortable) in Area B. This seven-point rating scale is similar to that in the investigation [7] .…”

“…Passenger comfort is an abstract concept that requires specific quantification; Sanok et al divided passenger comfort into seven levels and used the seven-point rating scale to investigate the influence of noise on pressure comfort. [7]. Tunnel length plays an important role on passenger comfort.…”

Control of interior surface materials for speech privacy in high-speed train cabins

“…As an increasing amount of time is spent in transport vehicles, the indoor environment of enclosed transport cabins should be considered in terms of not only thermal comfort and air quality but also acoustical comfort …”

“…As an increasing amount of time is spent in transport vehicles, the indoor environment of enclosed transport cabins should be considered in terms of not only thermal comfort and air quality [1][2][3][4] but also acoustical comfort. 5,6 High-speed trains are essential transportation systems in Asia and Europe, and research and development in the railway industry have been directed toward achieving higher speeds and eco-friendly characteristics. To develop an advanced high-speed train, the thermal comfort, air quality, 3 riding comfort, and acoustic comfort [7][8][9] of the indoor environment must be considered.…”