PVC and ABS solvent cementing


I know that the course materials say that joining ABS and PVC is not allowed, but that is only a partial answer. I can’t speak for everywhere and every jurisdiction, but in everyone that I have worked in, it is allowed if you use a special transition glue - which is typically white.
It’s still not good practice, but it is allowed in Canada.

I am just asking because I would like to know if there anywhere it actually isn’t. Does anybody know?

I have never heard of that either. I see it all the time and only call it up if they use the wrong glue.

Only at the transition between old and new work in my area and with the special green glue.