Analysis of information sources in references of the Wikipedia article "Elevator" in English language version.
A visible and audible signal shall be provided at each hoistway entrance to indicate which car is answering a call. Audible signals shall sound once for the up direction and twice for the down direction or shall have verbal annunciators that say 'up' or 'down.'
This 747, delivered to the Australian carrier in July 1971, was also the first to feature a lower-deck galley, reached by an internal elevator system.
This 747, delivered to the Australian carrier in July 1971, was also the first to feature a lower-deck galley, reached by an internal elevator system.
A visible and audible signal shall be provided at each hoistway entrance to indicate which car is answering a call. Audible signals shall sound once for the up direction and twice for the down direction or shall have verbal annunciators that say 'up' or 'down.'