I remember Herb Caen commenting a long time ago about the Golden Gate Bridge getting primered in silver when getting repainted, and the Bay Bridge getting primered in orange when it was getting repainted. I think parts of each bridge was almost always being repainted as part of their maintenance.
On the Golden Gate Bridge website it says:
The color dubbed “International Orange” existed before the Bridge (and still exists) and is a color used in the aerospace industry to set things apart from their surroundings, similar to safety orange, but deeper and with a more reddish tone. You can see this, the “other” International Orange color here:
http://en.wikipedia.org/wiki/International_orange. The Golden Gate Bridge is painted Golden Gate Bridge International Orange which was selected by Consulting Architect Irving F. Morrow.
https://www.goldengate.org/bridge/history-research/bridge-features/color-art-deco-styling/