Sunday, December 10, 2023

Modified air filtration box installed at Printshop

Charles Dickson
Quyon September 14, 2022
As we head into the cold and flu season, an improved air filtration apparatus has appeared at Pontiac Printshop to help reduce the spread of viruses. The device, based on the Corsi-Rosenthal Box developed in the U.S. at the height of the pandemic, was modified right here in the Pontiac.
Through the early months of the pandemic, it became understood that COVID-19 was not only transmissible by small respiratory droplets projected short distances by coughing, sneezing and even breathing.
Scientists around the world began to recognize that it was actually an airborne virus that could be carried on aerosols which are smaller, can travel further and linger in the air longer than droplets, and was therefore much more transmissible than earlier believed.
This led to a gradual shift in focus from lockdowns, distancing and hand-washing to masking, ventilation and air filtration as strategies to combat the spread of the virus.
It was in this context that two Americans, Richard Corsi and Jim Rosenthal, came up with a cheap and easy-to-make means of filtering airborne viruses out of the air.
It consists of four square furnace filters duct-taped together along their edges to form the sides of a cube. An upward-facing box fan placed on top draws air in through the filters and pushes cleaned air out into the room.
Known as the Corsi-Rosenthal Box, the do-it-yourself design makes it possible for virtually anyone to purify the air in daycares, classrooms, hospitals, work places and homes as well as or better than more expensive HEPA filtration systems.
In January of this year, four Corsi-Rosenthal Boxes were assembled and placed in different spaces within Pontiac Printshop to help reduce the presence of the virus for customers and staff alike.

Necessity gives birth to invention

The filters, which need to be at least of the MERV-13 standard in order to trap viruses, should be replaced every few months, which requires rebuilding the structure from scratch each time. The benefits of a reusable frame into which fresh filters could easily be inserted became apparent.
The idea to construct one out of wood was born, and Chuck Lalonde and Eric Dickson stepped forward to make it happen.
Chuck and his wife Amber Walpole operate a design and cabinetmaking business in the Quyon area known as Atelier Amberbrook.
They are primarily engaged in the creation of various sorts of installations for museums and galleries, but are also the driving force behind the barn quilt project that is putting colourful patterns on heritage barns across the Pontiac.
Eric Dickson, of nearby Beechgrove, has a keen interest in woodworking and is a good friend of Chuck and Amber. Together, Chuck and Eric came up with a plan that would use scrap pieces of wood typically found in any woodworking shop and built the reusable frame pictured above.
Thanks to them, as we move through fall toward winter, when windows and doors will be open less and less, our new and improved Corsi-Rosenthal Box, with easily replaceable filters, will keep whirring along quietly in the front office at Pontiac Printshop, helping to purify the indoor air.


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