Hi John – yeah, 9-degrees is a bit chilly! I don’t have any particular “air out” time for this exercise. You’ll be using the fan so it will be blowing all your odor to the start line and should be sufficient. It’s more important IMO to either move the objects that are holding the odor to the “new” configuration or remove the objects w/lingering odor.
Joyride K9 Dog Training