Tuesday, January 18, 2011

The Mystery of the Blue Sign Continues

As promised, I did some searching this weekend to try to discover why it is that pedestrian signs in much of Europe are blue, in contrast to the yellow signs found elsewhere in the world. Sadly, I have to report that while I did confirm that the current sign conventions were adopted in the late 1960s as part of the Vienna Convention on Road Signs and Signals, I have yet to identify anything definitive related to the blue color choice.

That said, I am dubious of the theory that blue signs are easier to see at night. While I wasn't able to find any research that examined blue signs specifically, I did come across one study that showed yellow and white signs are more visible at night than green signs. This suggests to me that blue might not be the best choice for pedestrian safety signs, despite Vienna conventions. This is not to say European sign standards have nothing on their American counterparts. After touring Erope on a quest to learn more about innovative traffic control practices, FHWA officials recommended the US adopt Europe's practice of increasing the saturation of color on traffic signs, regardless of shade.

Interestingly, I also came across a study suggesting that sign-makers have more to worry about that just color choice. This 2001 survey of five countries in the Middle East shows that age, gender, education and income all play a role in how well drivers understand signs. Young women with low incomes and low education levels had more difficulty understanding the intent of roadway signs thant their older, richer male counterparts--though even more disturbing was the fact that just slightly over half the drivers correctly identified all signs. As motorization rates continue to increase throughout the developing world, this could have dangerous implications for roadway safety--particularly of pedestrians.


  1. I didn't do any research, but I gave some thought to why I think this may be.

    Perhaps the color choice is more than an issue of visibility at night, but rather cultural context of colors. In most European cities, the pedestrian is normal part of street life, and colors like blue and green are more neutral or pleasant. Colors like red and yellow may be more visible, but in Western culture they also have a meaning of hazard , danger or aggression. I think in America we think of the pedestrian as not unlike the wild animals which cross roads with bright yellow hazard signs, a being which does not belong, is a danger, but is out there, so try not to hit one.

    Since travel speeds are slower in any place expected to have pedestrians in most European cities and towns, things like distance of sign recognition are probably less important than in the U.S., where it is not uncommon to have 50 mph speeds through areas with pedestrian crossings.

    I would be curious to know what thinking really went into the blue for crossing.

  2. You may be oon to something. I notice the wild animal warning signs in Europe are white with a red border. Parking signs, on the other hand, are blue--and we know how motorists feel about free parking...

  3. I wonder if any of the people on the board of Walk21, most of whom seem to be Europeans, would know? The board list and contact info is at: http://www.walk21.com/the_board/default.asp -- you'll see links to the board members who specialize in different areas (though I think the email for all is "info@walk21.com").