It’s been a long time since I looked into it, but IIRC the exposure time doesn’t make sense in a duct. RealSexyCyborg talked a lot about this during the pandemi

It’s been a long time since I looked into it, but IIRC the exposure time doesn’t make sense in a duct. RealSexyCyborg talked a lot about this during the pandemic. Though that analysis was limited to the Covid virus. Also to watch for: Some solutions produce irritants like ozone. Not to say they aren’t appropriate, just that they don’t come risk free. It would be a good question for that forum for sure.