Why Are Railroad Signals Red, Green, and Yellow (355)

A lot of folks are interested in why railroad signals are red, yellow, and green so I did a bit of research to see if I could dig up an answer form you. So in today’s video we’re going to take a loom at what I found. I also need to tell you that most of the photos and images I used are from the wikipedia website on Railroad Signals of North America and are provided under the creative commons usage agreement. I highly recommend this site for a general overview and you can find it at https://en.wikipedia.org/wiki/North_American_railroad_signals . For a deeper dive into this subject I recommend https://railroadsignals.us and https://www.mikeroque.com . Chapters 0:00 Intro 1:40 Ball Signals 3:34 Reading Moving Vanes 3:57 Smashboards 4:40 Semaphores 6:18 Banjo signals 6:57 Post 1900-Dr. Churchill 9:35 Red-shift 10:48 Target signals 11:42 Triple aspect 13:33 Wrapup