Yes and no.
Different states have different welding requirements. For instance I can weld in Maine and New Hampshire, but I don't have the right certifications to weld in MA.
In terms of shipyard welding, we are certified to US Navy standards which are different then bridge building and normal construction standards. There are some very important reasons for this, mostly because of the way steel absorbs the shock of explosions against the steel if the ship should hit a mine or see battle. It has to do with weld shapes, weld sizes and the process of welding, all involving some unique types of steel. For instance there are only 3 plants worldwide that produce the type of steel we primarily use, and only one plant is located in the USA. We also use a type of welding process that few welding shops would ever use, because it is a low heat (to prevent distortion) and yet penetrates well since most of what we weld is x-rayed.
Because of that, and because Bath Iron Works is known for quality ships, we were told we could get a job in any shipyard in the country. Now if I was to get laid off, or quit my job and go to another shipyard, I would have to retest at their facility, but being a BIW welder, they would know I already understand the uniqueness of welding a US Navy ship and they would not be wasted their money by having me go through the hiring process. But that is only if I quit or got laid off. I say that because we are often sub-contracted out as welders too. For instance, as I type this, BIW welders are on loan out in Hawaii rebuilding a ship there. Often times, the US Navy will insist other shipyards employ us when they run into trouble, because they know we will do the job right, and with US Navy ships, it has to be done right. In that case, we would not have to re-qualify for welding because we are not leaving our shipyard, just loaned out.
I really can't explain this into words; you would have to take a tour of the BIW to see what I am talking about. The quality and amounts of welds done, is just staggering. You have to really see it to understand.