At least one aspect of the invention is directed to a ventilation device. The ventilation device includes a frame configured to be mounted to a barrier, and a plurality of air moving devices configured to be coupled to the frame and configured to draw air from a first side of the barrier to a second side of the barrier. The ventilation unit further includes a control device coupled to the plurality of air moving devices and configured to detect an out of tolerance condition of one of the plurality of air moving devices and control another one of the plurality of air moving devices to increase airflow though the another one of the plurality of air moving devices in response to the out of tolerance condition.