Electra
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Ductless fumehoods - what are their limitations?
I've seen these advertised a lot for use in industry. I believe they use a combination of HEPA and activated carbon filters, but I wonder what are
their limitations? I think carbon is effective at capturing a lot of halogen compounds, phosphorous, sulfur, that sort of thing, but I can't see these
fumehoods fairing well with gaseous compounds that are not liquid at room temperature. Anyone here ever work with one of these ductless fumehoods?
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Dr.Bob
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Registered: 26-1-2011
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These are really meant for traces of organics, also powders, dusts, and some biologicals. I have not seen one that will handle any real amount of
solvents, corrosives, or toxics. I have seen them used more for analytical chemists who handle small amounts of materials and then make samples with
small amounts of solvents and then put them in vials or plates. They can work great for weighing samples as well. Those types of systems work
really well with dusts and powders, especially if they are more irritants than toxics. In fact, some regulatory agencies prefer those for dusts and
powders, since it avoids them going up a hood duct into the air.
But for most home lab uses, I doubt that they would be great, and the cost of the unit and their filters would be pricey. I would rather use box
fan in a window with a plywood box around it that one of those. But a simple hood with a 6" top duct, some sort of sash/window to reduce the air
flow needed, and a nice exhaust fan will work great, and can be built for hundreds of dollars. There are companies that make smaller, simpler
ventilated boxes for less money, and they are often available used for much less. They are ideal for putting chemical equipment into, but could be
used for some simple chemistry if vented well, and you are not making too many fumes. We used them for HPLCs, balances for powders or stinky (but not
highly toxic) chemicals, stinky chemical storage, and liquid handling equipment (liquid handlers working on 96 well plates and open vials).
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