For escalators, particularly public service escalators, potential misuse is an important issue. By far the most common occurrence is misuse of the emergency stop at the entry and exit areas of the escalator. Switching the escalator back on can take a long time, especially at stations where no staff are present. In order to reduce misuse of emergency stopping devices, in 1980 the escalator industry developed a switch that enables an automatic escalator restart. After a test phase this switch was adopted in 1991 by EN 115.2 Availability of the escalators in public service systems was thereby significantly increased (to a level of over 99% in Germany where the automatic restart switch is used by virtually all large operators). This switch has become such a success that hardly an escalator in Germany is not equipped with this feature. Retrofitting of automatic restart switches to older systems is also possible.