Markings Signs Handbook - Apron

: Solid white lines define the road edge, and dashed white lines separate lanes, sometimes using a "zipper" pattern for added visibility. Federal Aviation Administration (FAA) (.gov) Common Airport Signs The handbook and related FAA guides categorize signs by their background and text color: Federal Aviation Administration (FAA) (.gov) Apron Markings and Signs Handbook 2017 | PDF - Scribd

Here’s why it’s considered a definitive reference: Apron Markings Signs Handbook

: Fosters identical visual cues at all airports to reduce pilot and driver confusion. : Solid white lines define the road edge,