Assessment of the air pollution problems inside public transport interchanges in Hong Kong

Abstract

This research aims to identify the problems that exist in the public transport interchanges (PTIs) in Hong Kong. The study was conducted through literature review, semi-structured interview, site observation, face-to-face questionnaire interview and ventilation calculation. Based on the result of the questionnaire interview, most people commented that inadequate ventilation was the main reason of the poor air quality inside PTIs. Factors such as smoking habit, health status, environmental conditions and seasonal variations were found to be associated with people's perception and complaints. The study revealed that most of the PTIs in Hong Kong were enclosed by structural walls which would hinder natural ventilation. Under such circumstance, mechanical ventilation should be provided. However, most PTIs in Hong Kong were designed with low level mechanical exhaust system which is inefficient to capture vehicle exhaust gases. Instead, high level exhaust and low level outdoor air supply system is found to be a more efficient and cost effective solution. The provision of an air-conditioned queuing enclosure to separate passengers from the source would be desirable. The air quality problems inside PTIs can also be reduced to a certain extent through an introduction of stricter legislation and regulations.