I recommend ducted fume hoods.  The upfront cost is more, but that will be re-captured ( small pun).

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Ductless are more difficult to certify, loading of filters (cost of filter replacement), brea kthrough, leaking, etc.

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The TLV’s on your chemicals are so low that I wouldn’t want to rely on a ductless hood as a permanent option.  I only use ductless if there is a quick R&D need, and HVAC infrastructure is not in place, but only in the sho rt-term.

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John

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Dear colleagues:

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We are in the process of building a new Laboratory and contemplating between using Dustless Fume Hoo ds vs. Ducted Exhaust Hoods. We will be using a variety of hazardous chemicals including carbon disulfide, acetonitrile, toluene, benzene, some carcinogenic suspect chemicals, hydrogen sulfide and sulfur d ioxide gases.

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I appreciate sharing your experiences with ductless fume hoods and whether you recommend these type of hoods for hazardous chemical work using the aforementioned chemical examples as well as advantages and disadvantages of these hoods v s. the ducted exhaust hoods (safety concerns, costs, maintenance, etc.)

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Thanks,

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Michael Hojjatie, Ph.D.

R&D director, TKI