Written By: Marshal Sterio & Narrated By: Gayle Crew More than three years after a novel coronavirus was first identified in Wuhan, China, the world has learned a lot more about indoor air quality (IAQ) than most people probably wanted to. In the early days of the pandemic – as the transmissibility patterns of COVID-19 became clearer – country by country, state by state, and city by city, populations by the millions were ordered to shelter in place. COVID, many soon learned, was easily spread between occupants of shared indoor spaces. Preventing transmission meant avoiding indoor gatherings, even with loved ones.