Researchers at the University of British Columbia Okanagan are exploring an air-cleaning device that can remove airborne pathogens, offering a powerful new tool for reducing the spread of respiratory diseases in enclosed spaces.
The traditional approach to alleviating transmission of infectious diseases involves improving a building’s ventilation system to regulate large-scale airflow, explained Sunny Li, a professor in the School of Engineering.
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Personalised ventilation systems go a step further by directing clean air towards a person from a fixed distance – similar to the air circulation system on passenger airplanes. But these systems have drawbacks, he said. A person needs to stay in the same position, or all people in the surrounding area need to be using the same system at the same time. There is also the discomfort of dry skin and eyes due to the constant exposure to the air.
‘Ensuring high air quality while indoors is crucial for mitigating the transmission of airborne disease, particularly in shared environments,’ said Li. ‘Many Canadians spend nearly 90 per cent of their time inside, making indoor air quality a critical factor for health and wellbeing.’
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Postdoctoral researcher Mojtaba Zabihi explained that room layouts and ventilation systems vary significantly, making it challenging to implement changes in existing heating, ventilation and air conditioning systems. This highlights the importance of personalised ventilation.
‘We wanted to develop an innovative system that prevents occupants from inhaling contaminated air while allowing them to use a personalised ventilation system comfortably for extended periods,’ he says.
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The team of mechanical engineers, who work with UBC’s Airborne Disease Transmission Research Cluster, created an induction-removal or jet-sink airflow concept to capture and remove exhaled aerosols before they can circulate through the room.
Unlike conventional personalised ventilation systems, which rely on high-speed air jets that can cause discomfort and lose effectiveness when users move, the new design redirects airflow around the person while continuously drawing contaminated particles into a localised purification zone.
‘Our design combines comfort with control,’ said Zabihi. ‘It creates a targeted airflow that traps and removes exhaled aerosols almost immediately – before they have a chance to spread.’
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Using computer simulations to model breathing, body heat and airflow during a 30-minute consultation scenario, the researchers compared their device against standard personal ventilation systems.
The results were dramatic. The new system reduced the probability of infection to just 9.5 per cent, compared with 47.6 per cent for a personal setup, 38 per cent for a personal ventilation system with an exhaust design and 91 per cent under standard room ventilation.
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Under optimal placement, the device prevented pathogen inhalation for the first 15 minutes of exposure, allowing only ten particles out of 540,000 to reach another person. In fact, their simulations indicated it was able to remove up to 94 per cent of airborne pathogens.
‘Traditional personalised ventilation systems can’t adapt when people move or interact,’ explained Joshua Brinkerhoff. ‘It’s a smart, responsive solution for spaces like clinics, classrooms or offices where close contact is unavoidable.’
Brinkerhoff says the study highlights the potential for airflow engineering – not just filtration – to improve indoor air quality and occupant safety. Future research will focus on refining the design for larger rooms and testing physical prototypes in clinical and public settings.
The research has been published in Building and Environment.