Lutfi:
That's it? You got off easy... (Just kidding here.) Interesting reply.
I have been directly & indirectly involved with AISC, ICBO ES (IAS), ASME, ISO (QC system only for ISO) and jurisdictional certifications. Something I did not mention previously, there are many excellent fabricators out there who do an EXCELLENT job, all the time, everytime. There are also approved, certified fabricators who who can't seem to get anything right, even after several attempts. Some of these willfully ignore project and code requirements. Again, this is not a blanket statement.
Specifying an AISC or any type of approval is dependant on the certification/approval program, the rules and regulations of the program, the program directors and the auditor. I have witnessed AISC audits with several of my clients and not only did the auditor miss required check points, the ones they did address were incorrectly interpreted or applied. Recently monitored an audit (non-AISC) where the auditor was quoting incorrectly from the code & did not even have a copy of the fabricators QCP during the audit (how could he/she perform the audit without this document?)
This trade really does require an individual with experience in the trade and this same remark was made by one of the building officials during my last presentation. I know this is going to sting a little here, but some of these certification program directors do not believe you need to have experience in this trade and I whole-heartedly disagree with that mind-set. I mentioned previously I've had building officials request I monitor approved fabricators due to major screw-ups on the job. The shop drawings were some of the worst I have ever seen. I use these photo's for the "This is how not to do this" examples.
On the other hand, one (1) of my clients does not have any certification at all. The quality of the work, traceability, procedure/personnel qualifications, are excellent. They take it upon themselves to test welds they feel may be suspect (at their cost), qualify welders for each application and more. They build architectural structures all over the world and often have special inspectors present during fabrication. What they do need is a written QCP stating what they do to maintain quality and corrective action procedures. Another client works in the dirt with a canopy, the workmanship at this faciltiy would make you cry, it is excellent. I use their photos for my "This is how it's done" examples.
As you can tell, this is a subject dear to my heart. I have been in the welding industry for almost 30 years now in a variety of sectors (aerospace, structural, pressure vessels, etc.) IMHO, the scope and complexity of the project is what should determine the fabricator requirements. This is noted by JAE and which I do agree with.