A safety lock for a closing-off device which can be opened, has an actuating unit with an actuator which is guided in a displaceable manner, and has a locking unit into which the actuator, with the closing-off device closed, can be pushed and can be locked via an electromagnetically actuable, pivotable catch, by way of interengaging engagement surfaces, the actuator has a trigger element and the locking unit has a response element which, with the actuator pushed in, reacts to the trigger element by emitting an electric signal which triggers the locking action, in the case of which the catch can be pivoted about an axis extending parallel to the movement direction of the actuator, and the engagement surfaces of the catch and of the actuator run perpendicularly to the movement direction.