Cleaning.
New York City Transit Authority (NYCTA) R179 no. 3181 (Bombardier, 2016-2019) is the lead motor on a Manhattan-bound C train seen at its originating station: Euclid Ave. Car cleaners are stationed on the platform here, collecting trash, mopping floors, and performing other cleaning of the trains as they emerge from Pitkin Yard to re-enter service.