Abstract
To achieve uniform movement of air within an animal aerosol exposure chamber, and to meet animal husbandry requirements, we modified existing chambers in three ways: 1) air was introduced along the walls of the chamber; 2) catch pans were suspended away from chamber walls (except for the lowest level, which extended to the walls); 3) space between pans was allowed for exhaust flow. Each tier in the chamber acted like a perfectly-mixing box, resulting in clearance half-times of 3 to 6 minutes at a flow of 10 chamber equivalent volumes/hour. Concentration uniformity and aerosol buildup were measured in a full-scale chamber. We also demonstrated that measurements of flow visualization made in a reduced-scale, dynamically similar model were applicable to a full-scale chamber.