PURPOSE: To carry out an inspection work for confirming the operation of a safety device in short time by making a rear wheel diameter at any step among many steps smaller than that at the other step.

CONSTITUTION: A rear wheel at any step is replaced with a small diameter rear wheel 2a prepared for inspection. When a key switch for starting an escalator is turned on, the escalator is operated. Since the rear wheel is small in diameter, the rear wheel shaft 5, the moving locus of which is lowered, and a touch sense 4 are made in contact with each other to operate a safety device 3, turning off a switch and de-energizing a relay. Then the escalator is stopped. Thus, since the switch turned off by the operation signal from the safety device is of self-returning type, the escalator on which peeling off of a rear wheel tire is actually produced cannot be reset automatically when it is stopped, and the safety of the escalator is assured.