ISO 9809-4
Gas cylinders—Refillable seamless steel gas cylinders—Design, construction, and testing—Part 4: Stainless steel cylinders with an Rm value of less than 1 100 MPa
Published by International Organization for Standardization (ISO)
The CFR incorporates ISO 9809-4 by reference, which makes the edition it names part of the regulation. The CFR requires the edition it names, which may not be the newest. To enforce any other edition, the agency must publish the change in the Federal Register.
The edition the CFR requires
ISO 9809-4:2014, First edition, 2014-07
As the CFR lists it: “ISO 9809-4:2014(E), Gas cylinders—Refillable seamless steel gas cylinders—Design, construction, and testing—Part 4: Stainless steel cylinders with an Rm value of less than 1 100 MPa, First edition, 2014-07”
How to read it
- Where to get itISO Store ↗
A free or purchased copy may not be the edition the CFR names; check it against the edition above. Every incorporated standard can also be inspected at the National Archives (NARA) and at the agency named in the section that lists it.
ISO 9809-4 is copyrighted by its publisher; RegKnot shows its title and the editions the CFR names, not its text. Read from the eCFR's incorporation-by-reference sections, current as of October 26, 2026. The regulation text governs. All standards the CFR requires.