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Ventilation Design Handbook on Animal Research Facilities Using Static Microisolators 
• Room Air Change Rate: In addition to the basecase ACH of 15, three other ACH values 
were considered: 5, 10 and 20 ACH. 
• Change Station Design and Status: Two different change station designs were considered, as 
outlined above. The two designs were intended to present both a passive and intrusive 
influence to the room volume. In the case of the former design, the station was also 
considered switched off. 
• Pressurization of Room Relative to Corridor: The pressurization of a room is dependent on 
the difference between the supply and exhaust flow rates. A higher exhaust rate than supply 
leads to negative pressurization of the room, and hence makeup air is supplied to the room 
via available transfer mechanisms (namely door cracks). In this project, the amount of 
makeup air allowed through the door cracks was varied between 100 cfm (4.72e-l m 3 /s) into 
the room to 100 cfm (4.72e-l m 3 /s) out of the room. 
• Orientation of Cage Racks in Room: The racks were considered both parallel to the long 
walls and perpendicular to them. See figures 2.13 and 2.14. 
Figure 2.13 Racks Parallel to Side Walls 
