Coating selection starts with the actual exposure and project requirement. A generic label such as galvanized or coated is not a complete purchasing specification.
Describe exposure
Record indoor or outdoor use, moisture, salt, chemicals, abrasion, burial and contact with dissimilar materials.
Define appearance and handling
State visible faces, colour reference, gloss expectations, packing contact points and any site cutting or repair.
Agree on verification
Where records are needed, define the applicable test, sampling, acceptance criteria and documentation in the purchase agreement.