Evacuation valves
WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2007 Volvo V70, 2006 Volvo V70, 2005 Volvo V70, 2004 Volvo V70, and 2003 Volvo V70. However, it is still accessible from the selected car via links, so may be relevant.
In 4-door vehicles, the air vents are located at the edge between the parcel shelf and the rear windshield. The air goes from here through the cargo compartment and on out through the air vents behind the rear bumper.
In 5-door vehicles, the air passes directly out through the air vents in the cargo compartment.
There are rubber flaps in the air vents. The flaps open when the air pressure is higher in the passenger compartment that outside. When the air pressure is the same on the inside and the outside, the flaps close. This prevents water and air (odors, dust and exhausts fumes) from penetrating the passenger compartment.