Overview
EN ISO 13338:2022 - Gas cylinders - Determination of corrosiveness for the selection of cylinder valve outlet - specifies how to determine the corrosiveness of pure gases and gas mixtures so that a suitable cylinder valve outlet (connection) can be assigned. The document provides:
- a complete corrosiveness listing for many pure gases and some liquids, and
- a calculation method for gas mixtures (when experimental data are not available), based on the additivity approach of the GHS.
This standard is endorsed by CEN as EN ISO 13338:2022 and supersedes the 2020 edition.
Key topics and requirements
- Purpose: classify gases and mixtures by corrosive behavior to guide selection of valve outlet connections compatible with the gas.
- Classification system:
- FTSC subdivisions for chemical reactivity: 0 = non-corrosive, 1 = non‑halogen acid forming, 2 = basic, 3 = halogen acid forming.
- Tissue corrosiveness categories for living tissue: C = corrosive (irreversible damage), i = irritant (reversible damage), nc = non‑corrosive/non‑irritant.
- Pure gases: Table 1 in the standard lists corrosiveness categories and FTSC codes for a wide range of gases (and some vapourized liquids).
- Gas mixtures: where experimental data are absent, corrosiveness is determined using a calculation method based on the GHS additivity principle. Note: some valve‑outlet standards may require treating mixtures as corrosive regardless of component concentrations.
- Terminology and scope: definitions include tissue corrosiveness and irritancy aligned with GHS hazard classes; references to ISO 5145 (valve outlet dimensions) and ISO 14456 (compatible gas groups) are relevant for implementation.
Applications and users
- Who uses it:
- Industrial gas suppliers and producers - to mark cylinders and specify correct valve fittings.
- Cylinder and valve manufacturers - to design and specify outlet connections and materials.
- Gas distributors and filling stations - to match cylinder fittings to product corrosiveness.
- Safety, transport and regulatory professionals - to ensure safe handling, storage and transport of compressed gases.
- Laboratories, hospitals, and industrial end‑users - selecting compatible cylinder connections and mitigating corrosion risks.
- Practical benefits:
- Ensures compatibility between gas chemistry and valve connection, reducing leaks and safety incidents.
- Supports standardized, harmonized selection across supply chains and national markets.
Related standards
- ISO 5145 - Valve outlet connection dimensions for gas cylinders.
- ISO 14456 - Criteria for compatible gas groups.
- GHS (Globally Harmonized System) - additivity method used for mixture corrosiveness calculations.
Keywords: EN ISO 13338:2022, gas cylinders, gas mixtures, corrosiveness, cylinder valve outlet, FTSC code, tissue corrosiveness, GHS additivity, valve connections.
