The supermodel Cindy Crawford, in her famous 1992 soft drink commercial, almost made my eyes pop from their sockets.

But I managed to win a bet with my beer-drinking friends that I had more in common with her than they did.

My commonality with Ms. Crawford was that we both studied chemical engineering. She left my exciting world of organic chemistry for other pursuits and I went on to learn a few things as well. I learned how gases behave and about chemical refrigerants like ammonia, CFCs and R-32. I’ll bet Cindy never learned about how the cycle of compression and expansion of those chemicals with HVAC systems keep us cool during hot weather. Air is nothing more than a mix of chemicals, mostly Nitrogen, Oxygen, a host of trace gases, and water vapor. The much-ballyhooed Carbon Dioxide is at 0.04% but don’t worry as it takes a CO2 percentage of over 8% to be lethal, putting aside its greenhouse effects. But air can be lethal in another way. Extremely tiny viruses like today’s coronavirus can be transported from person to person via air. HVAC filters can trap larger particles like dust and skin cells, but the tiny viruses will pass through them as easily as they do through a face mask. One filter, known as a High-Efficiency Particulate Air or HEPA filter offers a ray of hope. Using a phenomenon known as Brownian motion the path of the virus through the filter is impeded causing a zig-zag movement that greatly increases its chances of being trapped in the fibers of the HEPA filter thus ending its ability to infect. For now, I’ve replaced the bedroom poster of my beloved Cindy with one of a HEPA filter.

Radiant floor heating