Make-up Air For Fume Hood 2

[Norm01]

I haven't encountered this problem before so I hope someone can provide me with some help. I currently have a lab room that is supplied with 180 cfm (being fed from a ceiling mounted heat pump). In the room is a recirculating bio-hood that the owner wants to convert to a fume hood, which will be exhausted at 650 cfm. So if I have to provide make-up air would it be in the range of 470 cfm?
If the exisitng heat pump doesn't have the capacity to accomodate this is there any cost efective way of providing the make-up air?
Thanks for any input.

 

[IRstuff]

Doesn't that depend on what requirements are imposed on the air quality for the fume hood itself? If no such requirements exist, you could just grab outside air with perhaps some HEPA filtering, since fume hood air is presumably headed for a scrubber anyway. You just have to make sure that the fume hood is still at a negative pressure relative to the room.

TTFN

FAQ731-376

 

[AbbyNormal]

get an inline fan, a good filter and an electric duct heater for the winter. An SCR controller on the duct heater will be a simple way to get the air tempered up to whatever temperature you want.



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