If you think restaurants are bad, and they are, you should try machine shops. I used to maintain CNC milling machines; one was in a shop that milled EDM sinkers[1] out of solid blocks of graphite. Graphite dust is a fracking nightmare. I quickly lost count of how many servo amplifiers and PLCs I had to replace.

[1] https://en.wikipedia.org/wiki/Electrical_discharge_machining