Corsi-Rosenthal Boxes as school-based learning activities

Making health and safety curriculum-friendly

In August of 2020, Richard Corsi (the incoming Dean of Technology at the University of California, Davis) was interviewed for an article in the magazine Wired.  It was during this interview where Corsi posited the notion of cleaning our air by strapping a MERV 13  filter to a box fan. Jim Rosenthal (CEO of Tex-Air Filters) heard about the idea and began experimenting with different designs to optimize efficiency, and shortly thereafter, a four filter cube design started spreading within various engineering circles. When asked to name the design, Rosenthal insisted that Richard Corsi’s name be associated and that he would be happy to have Richard’s name appear first in a hyphenated name: the Corsi-Rosenthal Box (CR Box). 

Naturally, as various engineers confirmed the science behind CR Boxes in conjunction with their low per unit cost of under $150, this technology started looking more and more like a viable way to help minimize the spread of COVID-19. It filters out approximately 85 percent of particles passing through the filters, making it a helpful tool to contain the virus. Additionally, Corsi-Rosenthal Boxes are also effective at screening out other airborne particulates such as pollen or pollution, which is ideal for our Northern communities since they are impacted by smoke from forest fires on a regular basis. 

By September 2021, our Teacher/Occasional Teacher Bargaining Unit in District 6B (Superior North) obtained the school board’s permission to incorporate CR Boxes into our courses as Rich Learning Tasks. One of the appealing aspects of the project is that it can be approached through multiple curricular lenses. For example, the project is an ideal fit for cience, Math, Geography, and Technology courses because it allows students to explore the scientific method, data sets, real world applications, and elements of design and integrated technology. However, this important step of permission was not the only obstacle that we had to overcome. 

Since Corsi-Rosenthal Boxes were new and unknown within the general population, our OSSTF/FEESO Members needed resources to be assembled so they had a starting point for incorporation into their courses. Our Bargaining Unit had to create background materials to explain what the boxes were, how they worked, and how they could be incorporated into various courses; we then sought out participation from Members in all the schools we serve. 

Fortunately, educators are well-versed in taking existing, commercially available products and using them in new ways to enhance their instruction. In short order teachers from all five of the schools we represent signed up to participate. Our Technology teachers chose to approach the project from an integrated technology lens, focusing on ways to design a frame that was reusable, yet aesthetically pleasing; whereas the Math teachers focussed on curricular strands that related to gathering data from laboratory and other sources, and organizing and recording the data using appropriate formats (tables, flow charts, graphs, diagrams). Meanwhile, our Geography teachers chose to centre the CR Box initiative within the Natural Disasters unit, with a specific focus on forest fire and wildfire preparedness.

When it came to securing funding for the project, our OSSTF/FEESO Teacher/Occasional Teacher Bargaining Unit approved a donation of $2500 to get the project started and we began contacting local businesses to start sorting through the logistical constraints faced by our communities. Fortunately, our local businesses and organizations stepped up in unexpected ways to ensure that we had the resources we needed to roll the project out in an equitable way.  

For instance, when I first called Cebrario’s Hardware to describe the project and inquire about product availability, Chris Cebrario was excited by the idea, and he offered to donate $500 in materials toward the project. This community support continued when I contacted Nipigon Canadian Tire to find out timelines for ordering additional filters and fans, and the owners enthusiastically offered to assist by discounting the cost of materials and by shipping materials to our neighbouring communities. 

As the project came closer to fruition, we reached out to our representative from the Ontario Teachers Insurance Plan (OTIP) to tell them about our project and the positive physical and mental health impact that it could have within the communities we represent. We explained that some CR Boxes would be used in classes and that some would be donated to “at-risk” populations within our communities. Seeing the benefit to our communities that this project would provide, OTIP surprised us with an offer to donate $500 dollars so that we could purchase more materials and build more filtration boxes!

As the scope of our project came into focus, the Bargaining Unit sought to interest our local Labour Council in sharing basic details of our project with affiliated unions. We had hoped that if enough people knew how inexpensive and easy it was to filter the air in their spaces, we could get widespread adoption, which would reduce the impact and spread of future COVID-19 waves. Our delegate to the Thunder Bay and District Labour Council put together a brief presentation regarding CR Boxes and their potential ability to reduce the strain on Ontario’s health care system. Fortunately, the Thunder Bay and District Labour Council not only agreed to share CR Box knowledge with their affiliated members, but they also donated $500 dollars to help us build more filtration boxes for our communities.

When all was said and done, each community hub was provided with one anemometer to measure air movement, one Air Quality meter (PM 2.5) to measure particulates in the air, five CSA approved box fans to power the filter boxes, eighteen Filtrete 2200 furnace filters to clean the air passing through, and enough duct tape to assemble it all. The students who participated in the project were very exited by their ability to engage in concrete actions that could make their loved ones safer, and the OSSTF/FEESO Members involved with the project also conveyed their sincere gratitude.

Looking back on the project, one can’t help but feel a swell of pride in how our Northern Ontario communities routinely come together to make meaningful improvements in our lives. 

Pictures courtesy of Les Barrett. Note: The photos above do not include the shroud (which optimizes efficiency and is normally located on top of the fan).