- American Iron and Steel Institute: https://www.steel.org/
- American Society for Testing Material: https://www.astm.org/
- Architectural Testing, Inc: https://www.testati.com/
- Copper Exclusive: https://www.copperexclusive.com/
- International Organization for Standardization: https://www.iso.org
- National Association of Architectural Metal Manufacturers: https://www.naamm.org/
- Underwriters Laboratory https://www.ul.com/global/eng/pages/
- Copper Development Association https://www.copper.org/
- Specialty Steel Industry of North America https://www.ssina.com/index2.html
- The Construction Specifications Institute https://www.csinet.org/
- RCI https://www.rci-online.org/
- TUV https://www.tuv.com/global/en/index.html
- RMI Titanium https://rtiintl.com/
- Alltrista Zinc https://allzinc.com/
- Stainless Architecture https://www.stainlessarchitecture.com/index.cfm/ci_id/17527/la_id/1.htm
- Allegheny Ludlum https://www.alleghenyludlum.com/