Hi, 

We are working on a CS V2009 project that is willing to control the parking garage ventilation by detecting contamination levels. According to ASHRAE 90.1-2010, the airflow should be reduced to 50% of design airflow. However, to achieve higher energy efficiency, the proposal is to shut off the fans during the night period, we want to know if this can be considered under section 6.4.3.4.4 where fans with motors greater than 0.75 hp shall shut off fans when not required. 

According to the owner's operation schedule, there is no intention to have traffic within the parking garage during the night. 

Thanks