Magnetic stripe fare cards may be purchased from touch-screen based vending machines, or ticket windows. A recend extension to the airport has met with wide approval, and was well-utilized during the 2000 Olympics. Double doors are placed offset from car ends at platform height, and car centers have a lower and upper level. Older carriages are not air-conditioned, but newer ones are. Four, six, and eight car trains are run.
Guards have a full height door and actually step out onto the platform at longer station stops.
Then they blow a police-style whistle to signal door closing. Cars are numbered with one letter and four numbers. Older cars are prefixed with C or T to indicate cab or trailer. The next two trains' destinations and arrival times are also displayed. Single low floor, three section articulated cars run in the street, and are powered by overhead.