Oh, I wish I could find the link... but it wasn't the title of one of his videos and he has way too many....
Dr. Campbell during one of his videos was reminiscing about the old days when he was a young nurse. He worked in a Nightingale Ward, which was named after Florence Nightingale. Did you know that she was instrumental in hospital designs? In a 22-month span between late 1854 and early 1856, Florence Nightingale oversaw a revolutionary overhaul of the British military health care system. The wards were what I would vision as a long army barrack, with windows on both sides and beds lining both sides but far apart. Perhaps you have seen them in the movies?
Dr. Campbell said first thing everyday would be to do some chores, feed the patients, etc. And then open all the windows on both sides to let the air turnover while they took their morning coffee. Afterwards, with the fresh air circulating and exchange, they would close the windows and only then change the dressings on wounds.
He spoke to the current designs of hospitals without recirculating fresh air and how it's contributed to noscomial/hospital acquired infections. In that video IIRC he said 17% of COVID patients were noscomial at one point in the outbreak. (Heck, that doesn't include the high number of staff at some)
Anyway, a good read here about Florence and hospital design.
King's Collections : Online Exhibitions : Florence Nightingale and hospital design