If you’re stuck in a place between a fume hood and a hard ceiling, consider using a filtered fume hood. Since more and more laboratories find they cannot duct out, or are choosing not to duct out in order to save on energy costs, there is a diverse range of carbon filtered fume hoods for most chemical fume hood needs.
A large misconception is that a ductless hood is the same across the board –with this being said, if you are interested in a ductless or filtered fume hood, be sure to have a list of chemicals and applications handy so a chemical assessment can be performed to see what type of enclosure is appropriate.
In my lab days, most fume hoods looked alike—a glass sash that could be raised or lowered, one switch for a light and another to turn air on and off. Today’s fume hood world features many options, including filtered hoods...
Read the entire article, Replacing Fume Hood Ducts with Filters Offers Newfound Freedom by Mike May.