Static field route #621

What do I do when stainless hardware touches aluminum, galvanized, or coated duct/supports?

Hanger Systems, Rods, Straps, Trapeze & AnchorsHigh-risk field starter — dissimilar metal check

Verify the dissimilar-metal detail before fastening. Stainless, aluminum, galvanized steel, coated steel, and other metals can react differently when moisture and corrosive air are present.

Open in Field Rescue Open category

Field checklist

Identify both metals
Check drawings/specs/submittals
Verify washers, isolation pads, gaskets, coatings, sealants, or approved fastener system
Ask before mixing hardware
Document any corrosion already present.

Ask foreman

This connection mixes metals. Is there an isolation, coating, washer, gasket, or fastener detail we need to follow?

Do not

Do not assume stainless plus aluminum or stainless plus galvanized is automatically safe in wet or corrosive air.

Why it matters

Dissimilar metals plus moisture can create galvanic corrosion risk.

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