Editorial policy and methodology

This site is published by Succession MFG, a manufacturing company whose team works with steel tube specifications daily. The publisher relationship is disclosed on every page footer. The site is an independent educational resource: it is not affiliated with, endorsed by, or a substitute for ASTM International or its standards.

Where sources could conflict, this publication treats them in strict order: (1) the current official ASTM edition; (2) producer certifications and documented capability for a specific order; (3) established industry references (AISC, Steel Tube Institute) and practitioner experience for explanation. Nothing in tier 3 is ever presented as a normative requirement. Each page's “Sources and limitations” section identifies which references informed it.

Content is drafted and reviewed by people who buy, specify, and process steel tube professionally. Review checks each claim against the source hierarchy above, verifies that qualitative characterizations of controlled content are fair, and confirms that nothing on the site could be mistaken for reproduced ASTM tables.

If you find an error, use the contact path at successionmfg.com. Confirmed factual errors are corrected in place and the affected page's modified date is updated. We do not silently rewrite substantive technical claims.

Every page shows a published and modified date. The modified date changes only when the page's substantive content changes — corrections, expansions, or edition updates — not for styling or navigation changes. When ASTM issues a new edition of A500/A500M, affected pages are reviewed against it and their dates updated on completion of that review.

Succession MFG funds this publication. No page's content is contingent on commercial outcomes, no producer pays for placement, and comparison pages are written to help readers choose the correct specification even when that choice sends business elsewhere. The only commercial link in the main content area is the disclosed publisher link.