Symbols

From AIGA.org:

The complete set of 50 passenger/pedestrian symbols developed by
AIGA is now available on the web, free of charge. Signs are available
in EPS and GIF formats.

About the symbol signs

This system of 50 symbol signs was designed for use at the crossroads
of modern life: in airports and other transportation hubs and at
large international events. Produced through a collaboration
between AIGA and the U.S. Department of Transportation (DOT),
they are an example of how public-minded designers can address a
universal communication need.