Hexavalent Chromium-Free Metals
Galvanized steel & metal hardware passivated without hexavalent chromium — same corrosion protection, no IARC Group 1 carcinogen.
Toxicity Screening — All Clear
This material screens clear across all seven independent toxicology authorities we use on every project.
Material Type
Trivalent-Chromium or Chromate-Free Surface Treatment
Material Description
Galvanized steel and zinc-plated hardware have historically used hexavalent chromium (Cr⁶⁺) chromate conversion coatings for corrosion resistance — a treatment that leaves a thin Cr⁶⁺ residue on every surface, exposing fabricators, installers, and demolition crews to an IARC Group 1 carcinogen. Modern alternatives use trivalent chromium (Cr³⁺), zirconium oxide, silanes, or phosphate-based passivation chemistries that match Cr⁶⁺ corrosion performance without the carcinogen. EBH specifies Cr⁶⁺-free passivation on all galvanized sheet, fasteners, and brackets — particularly important on products that crews will be cutting, welding, or grinding in the field.
Composition & Origin
Health Profile — All Endpoints Clear
Severity scored 0–10 against the same 10 hazard endpoints we use for the chemical families on the avoid list. Every score is 1–2 — essentially no signal across every endpoint.
Common Forms & Brands
- AkzoNobel Cr-VI-free passivation
- PPG / Henkel Bonderite Cr-free conversion coatings
- ZAM (zinc-aluminum-magnesium) galvanized steel
- Common framing: galvanized sheet metal, fasteners, brackets, joist hangers, structural connectors
Why We Use It
- Eliminates an IARC Group 1 lung-cancer hazard on every metal surface
- Matches corrosion-resistance performance of Cr⁶⁺ treatment
- RoHS and REACH compliant
- Reduces installer and demolition-crew exposure dramatically
- Verify with manufacturer's RoHS/REACH compliance certificate
Where It Performs Best
- Structural galvanized connectors (Simpson and equivalents)
- Galvanized sheet metal flashings
- Galvanized fasteners (screws, nails, lag bolts)
- HVAC ductwork and components
Building Applications for Hexavalent Chromium-Free Metals
Listed alphabetically. Where in a home this material earns its keep.
Flashing & Drip Edge
Galvanized Fasteners
HVAC Ductwork
Joist Hangers & Brackets
Roof Vent & Pipe Boots
Structural Connector Hardware
Hexavalent Chromium-Free Metals on a Bay Area Home
We specify Hexavalent Chromium-Free Metals because it survives the screening. Nothing goes into one of our homes until it clears all seven toxicology databases we check — that is what makes a toxin free home different from a home marketed as one.
If you are planning a new house or a deep remodel and you want this level of material control, that is the whole job we do. Earth Bound Homes builds in San Jose, Los Gatos, Santa Clara County and across the San Francisco Bay Area.