The velocity of air flow in a duct is typically expressed in which unit?

The velocity of air flow in a duct is typically expressed in feet per minute. This unit measures the speed at which air moves through the duct system, providing a clear understanding of how quickly air is being transported within the ventilation system.

Feet per minute is a relevant measure for assessing airflow because it directly correlates with the performance of heating, ventilation, and air conditioning (HVAC) systems. Knowing the velocity aids in calculating the necessary duct sizes and ensuring efficient system design. In HVAC applications, maintaining optimal air velocity is crucial for achieving desired temperature control and air quality.

Other units mentioned, such as gallons per minute and cubic feet per minute, are related to volume flow rates rather than the velocity of the air itself. Pascals is a unit of pressure, which is also not used to indicate the speed of airflow. Thus, feet per minute is the appropriate measurement for describing the velocity of air flow in a duct.