We were called to a rural Saskatchewan hospital to deal with a rare kind of disaster. Snow had blown into the attic, melted, and created large amounts of water damage in the ceilings. Because there were limited beds we could not shut down the entire wing so a temporary wall had to be built and the entire area put under negative pressure. In the three months it took to complete the job there was not a single complaint about air quality or related sickness due to air quality.