Railroad Regulations - By Time Period

I am trying to find information about federal regulations on locomotives and rolling stock and when they went into effect or were cancelled. So far, I have been able to find only the current regulations and a few odds and ends. I'm specifically looking for what rules and regs would have been in effect in the summer of 1986 as that is the time that I'm modelling.

I know that roof walks all had to be removed by then unless there were roof hatches but I don't know anything on when roller/friction bearings had to be replaced. I also see a lot of 80s pictures with amber beacons on locomotive roofs but I donk know when they start or end.

I also was looking for information on what had to be on the sides of rolling stock about that time. On many pictures from the 70s I see a rectangular box with colored stripes but they seem to be nearly all replaced by a black box with a white outline and white lettering by the mid 80s.

You are dealing with two different oversight agencies - the Federal Railroad Administration, and the Association of American Railroads. The FRA is the "heavier" of the two, their regs are backed by law. The AAR is an industry association and while they determine a lot of things they don't have the government behind their regs.

The black boxes with colored stripes were a predecessor of today's AEI tags. The different bars were coded to be read by scanners located at various points and the information (car number and initial) fed into computers. It proved difficult to keep the colored bars clean enough to work properly. Newer technology saw them replaced with the small plastic tags you see today mounted on the A-right and B-left sides of cars. That was an AAR thing, not FRA.

Friction bearings are STILL allowed on home-road cars, again an AAR thing not FRA. I can look to see if I have an exact date but pretty sure in early 80's they were still allowed in interchange.

Amber gumballs on loco roofs was likely railroad preference. FRA now mandates ditch lights on any loco operating as a lead unit which enters public grade crossings at speeds over 20MPH but I believe in the 80's there was no rule requiring anything but the headlight. Some roads DID choose to use strobes.

The black box with the white outline and letters is called a "consolidated stencil" and gives info about air brake and wheel bearing service data and dates. It started being used about 1970 or so, as an AAR interchange mandate.

Plain bearings were prohibited in interchange on revenue freight cars as of January 1, 1994. This is again an AAR ruling, not an FRA rule.