Who decided red means stop

The story I heard in physics class many years ago was “Red is for stop because England is foggy.” When they started night operations on the railways in England they chose red for stop. It was a fail-safe consideration, In a fog every light is red when seen at a distance. Thus the train would prepare to stop on seeing any light and then take whatever action is needed when it got close enough to see what colour it really was.

Welcome to the Straight Dope Message Boards, Keith, we’re glad to have you with us.

When you start a thread, it’s helpful to other readers if you provide a link to the column you’re discussing. Saves search time, avoids confusion, and stops people from repeating things that were already said in the column.

In this case, I presume , it’s Who decided red means stop?

No biggie, you’ll know for next time, and, as I say, welcome.

I also point out that, in the column, Cecil says red for stop goes back to Roman times, so it’s unlikely that it was because of British fog. We’ve learned never to believe what teachers tell us, outside their own area of expertise. And even then.

Looking at the original answer, I wouldn’t say that it says ‘red for stop’ goes back to Roman times. It might, but the comment offered was:

‘Red, the color of blood, has been a danger signal since time immemorial. It’s said the Roman legions bore the red banner of the war god Mars into battle 2,000 years ago.’

This says that red has been a danger signal for a long time (though no period is given), and that red was a colour associated with Mars for a long time (I suspect earlier than 2000 years ago if we are talking about Romans!). Association with Mars says nothing about it being a danger signal - you might just as well comment that the use of the famous red uniforms by the Parliamentary side during the Civil War in 1645 indicated danger.

I suspect that red was one of the few distinctive dyes which could be easily be made in antiquity, so the colour is old, but that the modern association with danger (in particular, an association with the need to stop) must be a function of the railways. This looks like the first time such a signal was needed.
Though I am not a railway expert, this site - http://www.du.edu/~etuttle/rail/sigs.htm - seems to give a comprehensive resume of the subject. It appears that early railway signalling (presumably entirely British, since they invented the things) was performed with flags. I assume there were few night operations. Red and White were common flags to use, with White often standing for ‘danger’. This makes sense - white should be the easiest colour to see in the day.

The site I reference gives extensive information about early signalling practices. There was no standardisation, however, until 1841, when the railways were being investigated. I quote the relevent paragraph below:
"The colours of the night aspects is a subject of some complexity. Even in the early days, a good red glass was available, and red and white (clear) were the colours used in signalling. In January 1841, faced with Parliamentary investigation and possible legislation, railway managers met at the Queen’s Hotel, Birmingham (later the Curzon Street station, and still standing) to discuss safety issues. Henry Booth of the Liverpool and Manchester was the driving force at this meeting, and contributed the results of 10 year’s experience on that line. The recommendations were essentially the practice of the Liverpool and Manchester Railway. Hand signals were standardized, and the signal colours of red, green and white were adopted. Blue signals stopped a train for traffic, and black flags were used by track workers. Red indicated Danger, White indicated Safety, and Green indicated Caution, Go Slowly. Green was introduced by this conference, and became generally adopted for Caution in all countries. As we have already mentioned, blue was used instead in America, though the adoption of green was soon noted. Green competed with blue, but did not completely replace it until after British signals were imported in the 1870’s. "
I would therefore submit that the answer to the question ‘Who decided that Red means Stop’ is Henry Booth of the Liverpool and Manchester railway, in a committee in Birmingham in 1841. I suspect that we can obtain the minutes of that meeting if we try hard enough!

To be pedantic on an essentially incidental point, the hotel was actually part of the station, which had been built in 1838. Also, while the main booking hall survives as one of the finest classical buildings in the city, most of the station has long since been demolished, including the wing that was the hotel.
This site seems to be the most detailed one online about the old Curzon Street Station.

Impressive! I take it that the rather nondescript building to the left of the Station Entrance is the Queen’s Hotel?

I noted that we might be able to find the minutes of the meeting - while the originals are almost certainly in England, I see that the Americans took a copy when they decided to follow the Brits, and a reference for this document is given:

“Rules and regulations, proposed to be observed by Enginemen, Guards, Policemen, and others, on all railways, recommended by the Railway Conference held at Birmingham, England, Jan. 1841 (Journal of the Franklin Institute, 33, pp. 239-242, 1842).”

I am presuming that the original question meant ‘Who decided that Red should be a UNIVERSAL signal for danger’; since in individual circumstances anyone can make up their own signals. In this context it is interesting to see that these regulations propose that non-railway employees (Policemen and others) are requested to observe them, which fulfills the requirement to be universal.

You may be reminded of the incident in ‘The Railway Children’ (Nesbit, 1906) when the children automatically knew that the appropriate things to wave to warn the train of an impending crash were their red flannel petticoats. I wonder if an earlier literary reference for the use of red as a danger signal can be found?

Yep. I may as well add that I’d infer from Pevsner’s comments on the former station in the original Buildings of England volume on Warwickshire that this building was still standing when that was published in 1966, though by then it was being used for offices (and probably had been for a century by then).

If it helps, the Journal of the Franklin Institute (which is still operating) was a very well known 19th century technical journal. Any US library that covers that sort of material is likely to have a run of it.