Measuring the thickness of the zinc coating

HOT DIP GALVANIZING SPECIFICATION
Hot Dip Galvanizing is very easy to specify due to the nature of the coating and the completeness of the CSA G164 specification.  The G164 specification comprehensively includes all items such as the required thickness of the zinc coating.

Part 1 - General
Material shall be Hot Dip Galvanized after fabrication in compliance with Canadian Standards Association (CSA) specification G164M-92:
Other References
American Society for Testing and Materials (ASTM) A143 Safeguarding against embrittlement.

Part 2 - Products
Steel Materials
Material for galvanizing to be geometrically suitable for galvanizing as described in ASTM A384 and A385.  Material to be chemically suitable for galvanizing as described in ASTM A385 and A143.

Fabrication Requirements
Material shall be fabricated for galvanizing in compliance with ASTM A385; Standard Recommended Practice for Providing High Quality Zinc Coatings (Hot-Dip) and referenced Standards A143 and A384.  Fabricate material in accordance with the AGA publication "The Design of Products to be Hot Dip Galvanized after Fabrication".  The fabricator shall ensure that all weld spatter and welding flux residue is removed.

Part 3 - Execution
Surface Preparation
Material shall be caustic cleaned, pickled to SSPC-SP8 and fluxed in an aqueous solution of zinc ammonium chloride.

Application of Coating
Galvanize material in accordance with CSA G164.  Repairs to correct bare areas may only be done if they meet the conditions of G164.  Repairs shall be done in compliance with ASTM A780.

Field Repair

Repair areas damaged by welding, flame cutting or during handling, transport or erection by one of the approved methods in accordance with ASTM A780 whenever damage exceeds 5mm in width or the base steel is exposed.

Quality Assurance
The galvanizer shall have a valid registration by a recognized authority to have a quality assurance program which satisfies the requirements of CSA Can3-Z299.4-85.

Delivery, Storage and Handling
Galvanized material shall be packaged and handled in such a way as to protect the zinc coating from damage.  Material shall be stacked or bundled and stored to prevent wet storage stain.