> His respect for the building's late mad architect rose a notch. The building wasn't merely designed by a paranoid, it was well designed. Every room had its own biolab grade filtration system, in addition to the central unit that filtered and flash-cooked all returning air to destroy possible poison gases or microbes, before it was recirculated or vented. [...] No colds were going to be transmitted among-personnel here.
-- Memory by Lois McMaster Bujold
Back in the real world, how practical would it be heat-sterilize the air used the average hospital?
I found this [0] suggesting that for SARS-Cov-2 it might take 3 minutes at 65C.
I imagine that then you have the problem of cooling the air again on its return, in which case it might be preferable to focus on longer cycles rather than higher temperatures, making the infrastructure larger for a lower energy use.