In a Jewish-owned and -operated mifa'al (factory/business), there is a room that is designated for the non-Jewish workers where they can eat, rest, etc. The room is used for nothing else (not even for storage purposes). Does the room need a mezuzah?
This site gives some excellent information about mezuzot and is worth browsing through. As you can see, from the part of it that I linked to, a room needs a mezuzah so long as it is either owned or rented by a Jew, whether or not it is a room in which people dwell.
The book reviewed here, by Rabbi Reuvain Mendlowitz, looks to contain a lot of excellent information on the question that you have asked as well, and will be available shortly.