Atlantic Coast Line put reflective hash marks called Prismo blocks along the bottom of many freight cars starting in the '50s.
Another off-topic aside, but it's interesting that Scotch Tape and it's various versions took it's name from basically an ethnic slur which originally denoted it's poor quality. The first 3M tape was a masking tape for painters, but they only put the glue on the outer edges, with nothing in the middle. This pretty much made the tape useless for paint masking, as one tiny opening on an edge would allow the paint to fill in the middle area. Painters figured 3M had used less glue because they were cheap, and because Scottish folks were stereotyped as being frugal, began to refer to it as "that scotch tape".
I see I forgot to mention that the GN's first use of Scotchlite was on some new boxcars. I think it was on some of their orange-painted ones. Intermountain shows a model that they call a Scotchlite version:
https://www.intermountain-railway.com/ho/html/46055.htm
Ed
7j43k I believe GN was the first adopter, in 1944. I think, at first, they did their heralds and the reporting marks. Then they dropped the herald, but added reflective "dots". Corporate headquarters for 3M (developer of Scotchlite) was in St. Paul, Minnesota. Corporate headquarters for Great Northern Railway was in St. Paul, Minnesota.
I believe GN was the first adopter, in 1944. I think, at first, they did their heralds and the reporting marks. Then they dropped the herald, but added reflective "dots".
Corporate headquarters for 3M (developer of Scotchlite) was in St. Paul, Minnesota. Corporate headquarters for Great Northern Railway was in St. Paul, Minnesota.
I know Northern Pacific diesels used reflective striping starting at least as far back as the 1950's. Hadn't thought about the Minnesota connection but it makes sense. NP was of course also headquartered in St.Paul (same building - sort of - as GN).
BTW I suspect most people don't know the three m's of 3M stand for Minnesota Mining & Manufacturing. The company started in Two Harbors, MN, not far from the Duluth & Iron Range (later Missabe Road) ore docks.
New York Central used "Scotchlite" or something similar on their Flexi-Van trailers in the late 1950s - early '60s:
2006 photos 620 by Edmund, on Flickr
Regards, Ed
Santa Fe used reflective circled crosses along the lower sides of some house cars before the switch to the rectangles. I think Rock Island tried reflectorizing their herald and lettering on some 40 foot boxcars in the '50s. It took the feds to mandate it.
Here's an article discussing UP's use of Scotchlite reflective material:
http://utahrails.net/pdf/UP%20Scotchlite%20article_as-published.pdf
Here's a shot of the UP Scotchlite probably taken in the '80's:
Back then, it seemed like EVERYONE was doing night shots of UP Scotchlite. I've got one I did myself, somewhere around here.
OK, so we know the Conspicuity stripe mandate on NA rolling stock from the 2000s (2005 IIRC, as detailed in this Federal document).That document mentions some experiments in reflective striping in the 1990s and before - for example is this Santa Fe PC&F insulated boxcar (Wheels of time link with prototype image) with short white reflective stripes along the sides.I don't recall this being particular common at the time, but now that I thought about it I see a decent number of images of pre-turn of the century rolling stock with such stripes (confirmation bias). Any good histories on the development and usage of reflective stripes -the FRA document I linked to just gives a broad overview and doesn't go into specifics, although it does note that improved reflective technology in the 1990s made such stripes viable for rail usage.