Hong Kong Chu Hai College delivered a press release on 12 July 2023 to announce the results of a study carried out by the Department of Civil Engineering on the air quality in public transport vehicles (buses and MTR train cars).  The press release was widely covered by local public media.

The research project was led by Professor Louis Lam, Head of the Department of Civil Engineering, and Dr. Celine Siu Lan Lee, Assistant Professor of the Department. Eleven (11) students participated in the project.

The research team used IoT-based portable sensor devices to measure the concentration of carbon dioxide (CO₂) inside double decker buses of long-haul routes from start to end of the journeys on both the upper and lower decks simultaneously.  The measured results were consistent and showed similar characteristics. A typical measurement on a bus from Tuen Mun to Lam Tin, with nominal travel time of 1 hour 40 minutes, recorded peak CO₂ concentrations on the upper and lower decks were 2,950 ppm and 2,840 ppm respectively. These concentration levels were approximately three-times higher than the guideline concentration level of 1,000 ppm for the “good class” indoor environment.

Measurements were also conducted in MTR train cars at different sections of the train. Results revealed that the measured concentrations, in general, were lower in the cars at the front sections. Typical measured peak values were 1,860 ppm for the route from Admiralty to Tsuen Wan and 1,426 ppm from Tuen Mun to Hung Hom.

Published research results of other research workers indicated that at the level range of 2,000 to 5,000 ppm, headaches, sleepiness, loss of attention, increased heart rate and slight nausea may occur.  As drivers stay inside public transport vehicles for a long period of time during their working hours, high concentration of carbon dioxide may pose potential health impacts and safety risks.  

During the press release conference, the research team demonstrated the use of the IoT-based air quality sensors to measure air pollutants and the potential of using similar methodology and equipment for air quality improvement in public transport vehicles so as to cope with the Smart Transportation initiative.

Prof. Louis Lam also announced during the press conference that the two civil engineering programmes offered by the Department, namely, the Bachelor of Engineering in Civil Engineering (Hons) and the Bachelor of Engineering in Construction Engineering and Management (Hons), were granted full accreditation by the Hong Kong Institution of Engineers (HKIE) in June 2023.  Graduates who enrolled to study the programmes in Academic Year 2019/2020 and thereafter can join the “Scheme “A” training of HKIE and thus allowing them to take professional examination and become Registered Professional Engineers in the shortest time after graduation.