I had a summer job at a Science & History museum.
I believe the title was "Maintenance Engineer", which means: Janitor.
I did mild electrical & plumbing work, helped load and unload at the docks during exhibit changeovers.
By far, I spent the majority of my time on-the-clock cleaning up around the "Discovery Zone". The science-field-trip catch-all area sustained the most foot traffic and incurred the highest rate of messes from kids being kids.
The Plasma Ball was always a huge hit.