js55
I don't know, I don't have that code but I imagine,(would think) if the code had the actual definition of a class 1 weld the O.P. would of seen it in the code, wouldn't it be in the front or back under definitions?.
I do not build rail car and I don't hear the crickets either, that is why I had my ¢¢'s showing.
Do you have AWS D15.1?
Marshall