150 CFM Chamber The 150 CFM chamber is 12 inches in diameter and 36 inches in length. The standard flow range is 3 to 150 CFM. The nozzle array is accessible through a removable panel for nozzle selection. The counter blower is mounted on the end of the chamber and uses a universal motor/variable transformer for speed control. This design does not utilize a blast gate and is typically used to determine system resistance and volume flow through power supplies and smaller electronic assemblies.