The ditch light era

[Rscott417]

I'm curious to know when ditch lights started to become implemented. I have a Conrail GP38-2 that'll be modeled after a prototype around 1995-98. The most recent picture I've seen of the prototype is in 1993 without ditch lights. I know there's always an exception to the rule with everything we come across with model trains but I would like to narrow it down. I'm leaning more towards installing them.

[faraway]

My rule of the thump is to add ditch lights on models after 1995. That is not technically correct but "most" US engines ran after 1995 with ditch lights as far I see them on tons of photos.
A more formal answer https://www.law.cornell.edu/cfr/text/49/229.125 The are multiple dates and amendments. But December 31, 1997 looks like a final mandatory date.

[Rscott417]

Thanks for the link Reinhard, I had 1995 in mind also... ditch lights it is.