Firemen and Deckhands' Union of New South Wales (FDU) was an Australian trade union existing between 1901 and 1993. The union covered deckhands employed on ferries, tugs, launches, lighters and hoppers, as well as enginemen, wharf hands, turnstill hands, change hands, firemen, motorboat coxmen and assistants. The FDU operated a closed shop, with all labour in the industry provided to employers through the union.