§ 203. Washrooms, washing facilities and waterclosets for elevator employees. There shall be provided and maintained for the use of all persons employed in operating freight or passenger elevators adequate and convenient washrooms or washing facilities and a sufficient number of suitable and convenient waterclosets. Where the elevator is used in or in connection with a factory or mercantile establishment, the provisions of sections two hundred and ninety-three and two hundred and ninety-five shall apply to wash-rooms, washing facilities and waterclosets for employees mentioned in this section; and where the elevator is used in any other building or place, the provisions of such sections three hundred and seventy-eight and three hundred and eighty-one shall apply to washrooms, washing facilities and waterclosets for employees engaged in the care, custody or operation of an elevator in such building or place. For the purpose of so applying the sections last referred to, the term "mercantile establishment" as therein used shall be deemed to mean and include a building in which the elevator is located or with which it connects.