PAIR Seminar: Prof. William P. BAHNFLETH delivers "How Can We Realise the Aspirations of Indoor Air Science? Lessons from 30 Years Spent Trying to Improve Indoor Air Quality"

Prof. William P. BAHNFLETH of The Pennsylvania State University, USA, presented a PAIR Seminar titled “How Can We Realise the Aspirations of Indoor Air Science? Lessons from 30 Years Spent Trying to Improve Indoor Air Quality” on 14 November 2025 at the PolyU campus.  The seminar attracted approximately 100 in-person participants and an online audience of over 21,300 across various social media platforms.

Prof. Bahnfleth commenced his presentation by outlining his research focus on the development of intelligent building systems that monitor and respond to changes in indoor air quality, aiming to create a healthy air environment for public health.   Drawing upon his extensive experience, he emphasised four key elements for successful research: clearly defining research objectives, fully engaging with the processes required to achieve them, breaking down disciplinary silos, and fostering effective communication with practitioners, the public and regulators.  He noted that the indoor air quality challenges faced by society during the COVID-19 pandemic are not new; they have existed throughout the history of the field.   

Prof. Bahnfleth further explained that a significant gap remains between scientific knowledge and practical application.  He asserted that this gap can be bridged, but only if we recognise that the major obstacles are not scientific nor technological, but pertain to human behaviours, risks and uncertainty, standards and regulations, regulatory processes and policy considerations.  He stressed that improving indoor air quality depends on broader engagement and cooperation, which is grounded in the shared vision and collective efforts of all stakeholders.

In summary, Prof. Bahnfleth expressed his firm belief that the success we pursue is attainable, provided we understand our current landscape, chart a clear path towards our goals, and persevere in the face of obstacles and setbacks.

The presentation was followed by a lively question-and-answer session moderated by Prof. CHEN Qingyan, Director of PAIR and Chair Professor of Building Thermal Science.  Both the on-site and online audiences participated in a productive discussion with Prof. Bahnfleth.

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