Waterloo PhD student teaches individuals how to build their own low-cost and efficient air purifier.

Ryan Tennant, a PhD student from the Department of Systems Design Engineering at the University of Waterloo, hosted a hands-on workshop for staff and students on August 27, 2023, where participants learned how to build their own affordable air purifier with performance comparable to commercial models.

Commercial air purifiers use a high-efficiency particulate absorbing (HEPA) filter, but these devices can be noisy and expensive. The DIY model already existed, but Tennant wanted to design his own version utilizing personal computer fans to generate comparable air flow while being significantly quieter. It also came equipped with colourful lights to provide a fun aesthetic.

Tennant received funding from the Centre for Bioengineering and Biotechnology (CBB) and the Graduate Student Endowment Fund to help lower the cost to participate, and offered free masks donated by CanadaMasq to all attendees. 

Inspired by online communities made up of engineers and innovative minds from around the world, Tennant discovered that he could design a local kit without shipping or duty fees using the tools available to him as a University of Waterloo Engineering student.

By utilizing the laser cutter in the Engineering building’s Rapid Prototyping Centre, Tennant worked to find the right dimensions and parts needed to make his vision a reality. After completing his design, Tennant sparked the interest of many community members, students and staff.

The DIY air purifier measures 16 in x 25 in x 7 in. It generates 340 cu ft per minute of clean air, uses the equivalent of one LED lightbulb at 20 watts of power, and produces a mere 38 decibels of sound. The device uses standard Minimum Efficiency Reporting Value (MERV) 13 filters to be replaced every six to 12 months.

With the outbreak of COVID-19 and other respiratory illnesses such as respiratory syncytial virus (RSV), and influenza, and the increase in wildfire smoke throughout Canada, the need for air purification solutions has become more apparent than ever. As of November 2020, all buildings across the University of Waterloo have been retrofitted for MERV13 filters that became standard over the pandemic because they are more effective at filtering air particles.

Motivated by his belief that clean air should be universal in every space, Tennant hopes to continue more advocacy work improving air quality in educational spaces and academic institutions so students and educators can learn in a space that will be safe for them.