First-level general contracting qualification of housing construction (steel structure) project Premium quality steel structure manufacturing enterprise Class-A engineering design qualification of building construction industry Class-A specialized contracting qualification of steel structure project Class-A qualification for steel structure engineering design China class-A special qualification of grid structure for steel structure manufacturer China premium qualification for metal cladding system contractor Class-A specialized contracting qualification of metal doors and windows Premium Qualification of architectural metal house (wall) design and construction S1 Qualification of Singapore national steel structure professional processing and installation Japan steel structure H level certification AISC certification of American steel structure production China laboratory metrology accreditation (CMA) Laboratory Accreditation Certificate by China National Accreditation Service for Conformity Asseccment(CNAS) Examination Board for Metallurgical Engineering Construction Qualification of Welder Qualification for Contracting Foreign Construction Projects from Ministry of Commerce