You must only use a ductless fume hood for which of the following?

A ductless fume hood is specifically designed to provide protection from hazardous fumes by filtering the air through charcoal or HEPA filters before recirculating it back into the room. Its primary purpose is to mitigate exposure to harmful vapors and particulates.

Using a ductless fume hood for non-toxic, low-hazard, and non-volatile chemicals is appropriate because these substances do not pose a significant risk. Since ductless fume hoods are not intended for the venting of hazardous materials outside, they are not suitable for more dangerous substances that could require more robust ventilation systems, such as toxic, flammable, volatile chemicals, or hazardous waste.

Choosing to use a ductless fume hood for non-hazardous materials ensures safety while still allowing researchers to perform their tasks effectively without unnecessary risk from more dangerous chemicals.