Reduction of Atmospheric PM2.5 Level by Restricting the Idling Operation of Buses in a Busy Station

Abstract

Fine particulate matter (PM 2.5 ) has been found to be harmful when inhaled by people, which has caused enormous health problems. It is found at high levels at public bus stations, where many passengers and workers may be exposed to PM 2.5 emissions from idling diesel engines. This study evaluated the restriction on idling vehicles as a strategy to control PM 2.5 levels at bus stations by measuring the PM 2.5 and the chemical properties at both upwind and exposure sites for comparable data. The sampling took place on weekends and weekdays and before and after the idling restriction was applied. Originally, the exposure site showed a PM 2.5 level that was 7% higher, non-neutralized nitrate content, anthropogenic metal elements, and higher mobile source contributions, as evaluated by a chemical mass balance model (CMB8.2). After the prohibition on idling heavy-duty diesel vehicles, the PM 2.5 mass concentrations at the exposure site were reduced to levels comparable to those at the upwind site. Additionally, the nitrate content was reduced in the background. Moreover, the contributions of several anthropogenic metals (Zn, Pb, Mn, Cu, Cr, V, Ni, and Ti) in PM 2.5 were reduced while those of crustal elements (Na, Mg, Al, K, and Ca) significantly increased after the restriction. Finally, the mobile contribution decreased to only 33.7-34.5%. Consequently, these findings verify that the prohibition policy on idling vehicles works well as a control strategy to manage the PM 2.5 emissions at local hotspots such as bus stations.

Public health implications of particulate matter inside bus terminals in Sao Paulo, Brazil

“…The fine particle concentrations found inside MASP bus terminals in the present study were lower than those reported for bus terminals in other countries. For example, the reported PM2.5 concentrations at bus terminals in Taiwan range from 35.4 µg m −3 in the city of Chiayi (Lee, Lin, Aniza, et al, 2017) to 51.7 µg m −3 in Taipei (Cheng, Chang, and Yan, 2012), which were approximately 1.2 and 1.7 times higher, respectively, than the overall average of all of the studies we identified in the literature (30 µg m −3 ). In the city of Brisbane, Australia, the average PM2.5 concentration inside bus terminals was reported to be 25.3 µg m −3 (Wang, Morawska, Jayaratne, Mengersen, and Heuff, 2011), approximately 1.3 times lower than the overall average.…”

Effect of the implementation of community activity restriction policies during the COVID-19 pandemic on air quality

“…It can affect the air quality in Jakarta or surrounding areas such as Serpong, which is a satellite city of Jakarta. Lee et al [20] stated that a vehicle in an idle position could increase the concentration of pollutants by 34%. Sarwar et al [21] noted that an idling engine would produce more exhaust emissions than a moving engine, and fuel consumption would increase to 1.8 gallons of fuel per hour.…”

Development of Transit Bus Idling Control Strategies Using Geospatial Information

“…(9) A study evaluated the restriction on idling vehicles to lower PM2.5 levels at busy bus stations. (10) As previously described, previous studies have focused on analyzing the characteristics of vehicle emissions during idling or the effects of applying ISG systems to transit buses. It is difficult to find studies aimed to establish traffic management strategies that mitigate the adverse effects of transit bus idling based on temporal and spatial frequencies and the density of idling resulting from the use of spatial information through a literature review.…”