Unidirectional airflow is controlled airflow through the entire cross-section of a clean zone with a steady velocity and approximately parallel streamlines, this type of airflow results in a directed transport of particles from the clean zone.Cleanrooms employing laminar air flow are typically referred to as unidirectional airflow cleanrooms.Unidirectional airflow is a way of ensuring air flows in only one direction, lessening the possibility of particles being kicked around and landing in your cleanroom.Laminar air flow refers to air that flows in a straight, unimpeded path. Unidirectional flow is maintained in cleanrooms through the use of laminar air flow hoods that direct air jets downward in a straight path, as well as cleanroom architecture that ensures turbulence is lessened. Laminar air flow utilizes HEPA filters to filter and clean all air entering the environment. Laminar filters are often composed of stainless steel or other non-shed materials to ensure the number of particles that enter the facility remains low. These filters usually compose roughly 80 percent of the ceiling space. Cleanrooms employing laminar air flow are typically referred to as Unidirectional Airflow Cleanrooms.