Taxiway Edge Lights
Blue lights or reflectors are used to outline the edges of taxiways during periods of darkness or lowered visibility.
Taxiway Centerline Lights
Some taxiways have installed centerline lighting to aid in taxi during low visibility. These lights are green in color.
Clearance Bars
Three yellow lights are sometimes installed on taxiways to increase the visibility of a holding position or indicate the location of an intersecting taxiway.
Runway Guard Lights
To point out taxiway/runway intersections, runway guard lights are installed at some airports. They consist of a pair of elevated flashing yellow lights installed on either side of the taxiway. Alternatively, they may be a row of in-pavement yellow lights installed across the taxiway at the holding position marking.
Stop Bars
Stop bars are sometimes installed to confirm air traffic control clearance to enter or cross the active runway in low visibility conditions. The stop bar consists of a row of red lights installed across the taxiway across the holding position. Air traffic control turns the stop bar lights off and the taxiway lead-on lights on with the issuance of the clearance to proceed. In this way, the lighting systems act to confirm the clearance to proceed onto the runway. A sensor resets the lights for the next aircraft.