Yes, apartment too large and poorly sealed. > Typically it is harder for a filter to clean the air in your apartment when you are bringing in extra outside air

Yes, apartment too large and poorly sealed. > Typically it is harder for a filter to clean the air in your apartment when you are bringing in extra outside air That was my point. Bringing in outside air would be a luxury. Btw just ordered passive filters for the windows for super cheap- perhaps that will move the needle on how much outside air we can bring in while maintaining indoor AQI. Still curious about the positive pressure idea. If it’s effective, I’d expect someone to productize it.