I've also asked around the managers of my office about this, but this came up in my union work recently and I thought I'd find out what everyone thinks.
Poll #7675 Reasonable ad-hoc tasks
Open to: Registered Users, detailed results viewable to: Just the Poll Creator, participants: 57
You employ a person whose normal job is to do post opening, stamping, preparation of papers, scanning - adminstrative tasks, in other words. Would you regard it as reasonable for them to be asked to do "sweeping out the filthy basement" as an ad-hoc task?
Yes
3 (5.3%)
No
9 (15.8%)
In the context of an office move or "tidy friday" when everyone's mucking in, but not otherwise
44 (77.2%)
Something else I will tell you about in comments
1 (1.8%)