Now, negative pressure rooms are just that, they have slightly lower pressure than the adjacent room so that air leakage is one way…into the NP room, preventing whatever cooties the patient inside the room has from getting out into the hallway or through the door.
This, of course, requires a bit of fine balancing of air out vs air on, and some pretty powerful fans and/or other air handlers. Generally, the NP rooms also get the air changed more frequently, like 10-12 times an hour.
Modifying the airflow in a set of rooms from “normal” to Negative Pressure is not a trivial task.
One has to find some way to handle the additional airflow, to heat (or cool) the increased incoming air to environmental standards (likely 65-70 degrees F) to balance that airflow correctly and some way to handle the infectious materials that may be in that air you are exhausting from those rooms.
Since the hospitals are doing this “quickly” I don’t think I would want to spend much time breathing the air around the outside of the hospital. You are talking at least 5 times the air quantity of a “normal” room and that air has to be somehow filtered for the diseases that the patients have. The filtering/germicidal devices that are in place to filter for the rooms that already exist won’t work well if they are expected to handle 2 or three times as much air volume. And you can’t just easily add to such devices on a moment’s notice….they need to be ordered and custom built and tested and adjusted before they can be used.
Lots of air, handled quickly, and now at a greater load for that filter or germicidal device to make the air safe for the rest of us. All done in a “hurry”…I’m glad I don’t live downwind of a hospital that has covid cases.
Yeah, I feel safe about it. You should too….
Talk about community spread… sigh
Same here in SE Wyoming. Meats are back, as are veggies though the veggies are of a bit poor quality for the fresh ones. No TP almost no paper products, cleaning stuff is still in short supply, beans, rice, pasta are in short supply. No yeast to be had either. My read on it is that there is not much stuff out there, most of it was pushed out as things kicked off for the insanity. So the warehouses themselves and further upstream are still trying to get things to the warehouses in any quantity. That stuff like medical supplies is now allocated in smaller amounts for the stores. Then it finally gets to the stores, goes on the shelf, it looks like a tiny amount (it is in comparison) and everyone panic buys a pack or two again..