Ok in a previous post regarding a company that I may be doing business with I stated that they are doing retrofits removing the magnetic ballasts and replacing with the new electronic ones. The ballasts that are being removed were non-pcb type which are supposed to be clearly marked on the spec sheet that are attached to the ballast. The ballasts if not marked that way or the paper being missing or unreadable I will not take due to the fact that the yards I deal with have stated " if one ballast in the lot is not marked as non-pb we will not accept the entire load". As far as telling the difference if they are not marked I have no idea. The op asked about ballasts from the 1960's. I answered that anything that old that he should watch out for the pcb in them. If you are going to scrap ballasts you should call your yards to see what they accept. Check out waredu post above and the link he attached. That's a pretty good list that is on there.