Overview
ISO 9626:2016 specifies requirements and test methods for rigid stainless steel needle tubing used in the manufacture of hypodermic needles and other medical devices for human use. The second edition (2016) updates dimensional and mechanical requirements, adds very thin metric sizes (down to 0.18 mm / 34G), and refines wall-thickness designations (RW, TW, ETW, UTW). It applies to rigid tubing; flexible stainless steel tubing is excluded (though its dimensions are recommended).
Key topics and technical requirements
- Scope and materials
- Applies to rigid stainless steel tubing for needles; steels are referenced to ISO 15510.
- Manufacturers should consider biocompatibility (see ISO 10993-1) when selecting steels for drug contact or long-term use.
- Dimensions and size designations
- Tubing sizes are given in designated metric outer diameters (e.g. 3.4 mm = 10G down to 0.18 mm = 34G) with corresponding inner diameter limits and wall classes.
- Wall thickness categories: Regular Wall (RW), Thin Wall (TW), Extra Thin Wall (ETW), Ultra Thin Wall (UTW).
- Mechanical properties and performance
- Stiffness testing and pass/fail deflection limits are defined (see Table 2 and Annex B).
- Resistance to breakage (Annex C) - tubing shall show no visible breakage under test conditions.
- Surface, cleanliness and chemical limits
- Surface finish: outside surface must be smooth, straight and free from defects on visual inspection.
- Cleanliness: free from metal soil and processing agents.
- Limits for acidity/alkalinity: extract pH (Annex A) must be within one pH unit of the control.
- Corrosion resistance
- Corrosion test methods (Annex D) require no evidence of corrosion on the immersed half of the tube.
- Sampling and risk-based approach
- Sample sizes, additional tests and final acceptance criteria are based on risk assessment and intended device use.
Applications and users
ISO 9626 is essential for:
- Needle tubing manufacturers establishing product specifications and quality control.
- Medical device OEMs and component suppliers designing hypodermic needles, injectable-device components and related assemblies.
- QA/QC and testing laboratories performing dimensional, mechanical and corrosion tests.
- Procurement and regulatory teams specifying compliant tubing for human-use devices.
Practical benefits include consistent needle performance, regulatory alignment, reduced device risk, and clearer supplier specifications.
Related standards
- ISO 15510 - Stainless steels: chemical composition
- ISO 3696 - Water for analytical laboratory use (used in extract preparation)
- ISO 10993-1 - Biological evaluation of medical devices (biocompatibility guidance)
- ISO/TR 19244 - Guidance on transition periods
Keywords: ISO 9626, stainless steel needle tubing, hypodermic needles, needle tubing dimensions, tubing stiffness test, corrosion resistance, medical device manufacturing.