Overview - ISO 13769:2018 (Gas cylinders - Stamp marking)
ISO 13769:2018 specifies the requirements for stamp marking of transportable gas cylinders and tubes (volumes > 0.12 L up to ≤ 150 L and tubes up to ≤ 3 000 L). It covers steel and aluminium-alloy cylinders, composite cylinders (including hoop-wrapped), acetylene cylinders, LPG cylinders (Annex A) and small cylinders (Annex B). The standard applies to refillable and non‑refillable cylinders and is written to be compatible with the UN Recommendations for the Transport of Dangerous Goods - Model Regulations.
Key topics and technical requirements
- Scope of markings: Manufacturing, operational and certification marks (see Table 1 and Annex C). Examples include manufacturer identification, manufacturing serial number, inspection stamp, initial test date, test pressure and empty weight.
- Permanent vs durable marking:
- Permanent marking: hard metal stamping, engraving, casting, or encapsulated labels (required for most refillable cylinders and many composite designs).
- Durable marking: stencilling, labelling or tagging is permitted for certain items or on small cylinders.
- Specific marks and symbols:
- NDE indicators: UT, MT, PT, AT for ultrasonic, magnetic particle, dye penetrant and acoustic emission tests.
- Material compatibility: “H” (hydrogen-compatible steel) and “HG” (high-grade stainless steel).
- Test pressure: prefix “PH” plus value in bars (e.g., PH300BAR).
- Mandatory “UN” mark sizing and minimum character heights.
- Workmanship and safety:
- Markings must be legible, durable and not weaken the cylinder. Tool radii (suggested ≥ 0.2 mm) and depth must avoid sharp notches; fatigue and burst testing may be required to demonstrate safety.
- For composite cylinders, labels can be encapsulated under resin or covered by a permanent coating; hoop-wrapped cylinders require duplicated manufacturer ID on the shoulder for traceability.
- Arrangement and placement: All marks must follow the sequence and layout conventions detailed in Annex C; Annex A and B provide placement examples for LPG and small cylinders respectively.
Applications - who uses ISO 13769:2018
- Cylinder manufacturers and fabricators (design, production and permanent marking)
- Inspection and testing bodies (initial and periodic inspection marks)
- Gas suppliers, transporters and regulatory authorities (traceability, transport compliance)
- Engineers and quality managers responsible for cylinder safety, compatibility and conformity with UN Model Regulations
Related standards and references
- ISO 10286 - Gas cylinders terminology
- ISO 11114-1 - Compatibility of cylinder and valve materials (metallic)
- UN Recommendations for the Transport of Dangerous Goods - Model Regulations
ISO 13769:2018 is essential for ensuring standardized, durable, and safe stamp marking practices across the gas cylinder supply chain, improving traceability, regulatory compliance and operational safety.
