Can an F1 international student in the United States who is employed 20 hours per week as a teaching assistant or research assistant perform some volunteering work that potentially grant him/her some privileges? I know that (s)he isn't allowed to perform paid work as the F1 visa doesn't allow him/her to work over 20 hours per week, but I am blurry regarding "semi" (i.e. granting privileges as in the example below) and fully volunteer work.
Example: Bob is an F1 international student in the United States. He wants to say in the same dorm next year. The dorm administration propose him to perform some dorm duties (e.g. organizing social events in the dorm, watering the plants, etc.) and in exchange he will be guaranteed to stay in the same dorm next year. Can Bob do that without violating his F1 visa?