Ask Rick: High Plume Dillution Fans | Is the motor out of the airstream? Posted January 30, 2012 by Jim Shiminski FacebookTwitterLinkedin Q. On the Strobic Air Tri-Stack Fan is the motor out of the exhaust airstream? A. Yes, the fan motor is outside of the exhaust airstream. This is true for Strobic Air and for all High Plume Dilution Fans (Laboratory Fume Hood Exhaust Fans). Leave a Reply Cancel replyYour email address will not be published. Required fields are marked *Comment * Name * Email * Website Save my name, email, and website in this browser for the next time I comment.