Deals with an individually ventilated caging (IVC) system with precisely controlled unidirectional airflow developed and evaluated relative to bedded polycarbonate cages. The aim was to deign an individually ventilated caging system that permits precise control of air velocity approaching the cage, to evaluate the individually ventilated cage relative to a bedded polycarbonate showbox cage and to determine the influence of cage population density on cage microenvironment and rat response using the IVC system. Explains the experimental design and procedure and supplies the results. Reaches positive conclusions.

KEYWORDS: Ventilation, laboratories, site testing, animal housing, polycarbonates.