On particulate emissions from moving trains in a tunnel environment. (March 2018)

• Record Type: Journal Article
• Authors: Cha, Yingying; Olofsson, Ulf; Gustafsson, Mats; Johansson, Christer
• Is Part Of: Transportation research. Volume 59(2018)
• Page Start: 35
• Page End: 45
• Publication Date: 2018-03
• Subjects: Railway tunnel -- Airborne particulates -- Individual train -- Particle number concentration -- Particulate size distribution; Transportation -- Research -- Periodicals; Transportation -- Environmental aspects -- Periodicals; 354.76
• DOI: 10.1016/j.trd.2017.12.016
• Languages: English
• ISSNs: 1361-9209

Abstract

Highlights: The operation of the trains affect the particle size distribution observed on the platform. Particulate number concentration is dominated by a 170-nm mode when a train passes through the station. Different types of train make different contributions to particulate size distribution. Abstract: Increasing attention is being paid to airborne particles in railway environments because of their potential to adversely affect health. In this study, we investigate the contribution of moving trains to both the concentration and size distribution of particles in tunnel environments. Real-time measurements were taken with high time-resolution instruments at a railway station platform in a tunnel in Stockholm in January 2013. The results show that individual trains stopping and starting at the platform substantially elevate the particulate concentrations with a mobility diameter greater than 100 nm. Two size modes of the particulate number concentrations were obtained. A mode of around 170 nm occurs when a train moves, while the other mode peaks at about 30 nm when there is no train in the station. By using principal component analysis (PCA), three contributing sources were identified on the basis of the classification of the sizes of the particles, namely railway-related mechanical wear, suspension due to the movement of trains and sparking of electric-powered components. It is concluded that the particulate matter released by individual moving trains is a key contributor to fine particles (100–500 nm) on the railway platform in a tunnel.