Bolts, nuts and washers need to be "double galvanized" for the ACQ wood treatment. Indeed, screws need a special coating as well. Our government in a rush to remove arsnic from wood treatments has left us with the current mess. I have sold fasteners and lumber for 25 years. The feds went through my inventory and 12 months of records in a surprise visit to ensure the old pressure treated lumber was no longer retailed. The new treatment has a habit of "eating" my steel racking. I assume homeowners will have failures down the road, leading to deaths and litigation.

Yikes. Thanks for the info.