Spot exhaust is a unique design engineering challenge. The 2015 ASHRAE Handbook – HVAC Applications covers a broad spectrum of applications in just about all the comfort applications (chapters 1 through 13) and industrial applications (chapters 14 through 33) with personal safety an integral part of chapter 32. But spot return air doesn’t get much press in ASHRAE.
Obviously, there is localized exhaust when using a fume hood or when connecting an exhaust duct to an automobile exhaust pipe when the car is running inside a shop. Kitchen hoods also provide localized exhaust, but what about localized return air? Localized/spot exhaust has its own chapter in the 2015 handbook and the American Conference of Governmental Industrial Hygienists (ACGIH) publication, “Industrial Ventilation: A Manual of Recommended Practice for Design,” is an excellent source for localized exhaust. So why don’t ASHRAE and other organizations provide guidelines for good return air distribution that will also be cost-effective?