I guess the more general question is - can a manual on/off switch be installed within a control panel where the user would be exposed to live parts to flip the switch?
As I recall, without looking it up, if the live parts are at a higher potential than "low voltage" parameters allow (e.g. 42.4 or 49 volts, depending upon circumstances), then UL standards for commercial equipment generally require them to be protected from "contact" by a user or operator, during ordinary operation.
When I did UL testing on high-end computer prototypes (in the 80s), we had a "standard finger probe"
hmy: that we used for testing whether any live parts could be reached through any openings, when the covers were on and the service access doors were locked (with a key, which is considered a "tool" available only to authorized technicians). If the voltage measured at the fingertip exceeded 42.4 volts, the design failed.
I don't know what the particular standards are for "fume hoods", but my guess (FWIW) is that they are bound by a similar standard of user safety from electrical shock, which I can't quickly access at the moment.