An apparatus for performing an operation on a circuit substrate, the apparatus including a plurality of operating devices which are provided in a space that is closed and opened by a safety cover and one of which performs the operation on the circuit substrate, a safety-cover switch which is switchable to an ON state thereof corresponding to a closed state of the safety cover, and to an OFF state thereof corresponding to an opened state of the safety cover, a maintenance-related control device which keeps, in a maintenance mode, at least one of the operating devices to a state thereof in which the one operating device is operable, and a maintenance-mode setting switch which cooperates with the safety-cover switch to provide a parallel circuit, and which is selectively operable to an ON state thereof in which the maintenance-mode setting switch allows setting of the maintenance mode, and to an OFF state thereof in which the maintenance-mode setting switch does not allow the setting of the maintenance mode.