Reference NFPA 101 2009 Edition par 18.104.22.168.3 states " Where the air in ducts continues to move and air handling system installed is arranged to prevent recirculation of exhaust or return air under fire emergency conditions."
I'd like to clarify is this meant for both exhaust or return air. My understanding is that when we say "exhaust air" is that it is air thrown out of the building and return air is the one that is recirculated. Shouldn't this paragraph state only for return air. Please advise..