Overview
ISO 13926-3:2019 - Pen systems - Part 3: Seals for pen-injectors for medical use specifies the shape, dimensions, materials, performance requirements and labelling for seals used in pen‑injectors. It focuses on the primary‑packaging seal (aluminium cap + elastomeric disc) whose properties can materially affect the potency, purity, stability and safety of medicinal products during manufacture and storage.
Key topics and requirements
- Scope and classification
- Applies to seals for pen‑injectors; seals are classified as Type A (mono‑layer disc) or Type B (double‑layer disc).
- Shape and dimensions
- Standardised cap and disc geometries and tolerances are given (nominal sizes and dimensional rules); surface structuring is allowed to avoid sticking.
- Materials
- Caps: aluminium caps must conform to ISO 8872 and be anodized or suitably coated.
- Discs: elastomeric formulations must be the type originally tested and approved by the end user; manufacturers must ensure conformance to the agreed type sample.
- Elastomeric discs shall withstand two autoclave cycles at 121 ± 2 °C for 30 min without functional impairment (other sterilization methods must be evaluated).
- Physical performance
- Hardness: agreement between manufacturer and user; typical tolerance ±5 Shore A (or ±5 IRHD when applicable).
- Fragmentation: testing per ISO 8871‑5 using a medical needle (reference to ISO 7864).
- Freedom from leakage: mandatory leakage test (normative Annex A) using water‑filled cartridges and a defined force applied for a set time interval.
- Resealability: requirements reference ISO 11608‑3.
- Resistance to ageing: seals must maintain performance over the medicinal product’s shelf life (storage guidance per ISO 2230).
- Chemical and biological
- Labelling and designation
- Standard designation format e.g. “Seal ISO 13926‑3 – 7,5 – A”.
Practical applications and users
ISO 13926‑3 is intended for:
- Medical device and pen‑injector manufacturers (design and production)
- Pharmaceutical companies specifying primary packaging for injectable drugs (e.g., insulin pens)
- Elastomer and cap suppliers for qualification and incoming inspection
- Quality assurance, regulatory affairs and procurement teams for supplier agreements and stability programs
- Test houses validating leakage, resealability, sterilization compatibility and ageing
Using this standard helps ensure component interchangeability, product safety, compatibility with sterilization processes and consistent performance over shelf life.
Related standards
Relevant referenced documents include: ISO 13926‑1, ISO 13926‑2, ISO 8871 (parts 1,4,5), ISO 8872, ISO 11608‑3, ISO 48‑4, ISO 7864, ISO 15378, ISO 2230.
Keywords: ISO 13926-3:2019, seals for pen-injectors, pen systems, elastomeric seals, leakage test, resealability, medical device packaging, pharmaceutical primary packaging.
