Different trades have different welding requirements but it is common for a welder to have to pass "certification" tests for the particular job or company he works for. Specialized projects can require their own certification and even a long time welder will have to pass the tests for that project. That being said, a huge ammount of maintenance welding is done by whoever says they can weld. I welded on ammusement rides and never was tested for anything. As far as a helmet, I've got an autodark 9-12 unit. I love the automatic feature but, at 55, my eyes are not a sensative as they once were and I am finding shade 9 a tad to dark with my flux cored wire welder in varing outside lighting conditions. I recently found one advertised that claims 7-12. I am going to look at it closer.
