USP <382> Is Now Official: What the New Requirements Mean for Closures

This article explains what USP <382> covers, what its move to official status changed, and what it means in practice for elastomeric closures and the seals applied over them.

Key takeaways

• USP <382> became official on December 1, 2025, after a multi-year transition since being incorporated into the USP-NF in 2020.
• It addresses the functional suitability of elastomeric components (penetrability, self-sealing, and contribution to package integrity), separate from the material requirements in USP <381>.
• The functional content that historically sat within <381> was moved into the dedicated <382> chapter, so the two no longer overlap.
• Functional suitability is assessed for the component in its actual packaging system, with the specific vial and seal, not in isolation.
• The change reinforces a two-part qualification: <381> for the material, <382> for the function.
• The exact tests, methods, and acceptance limits are defined in the current USP-NF text, which is the controlling reference.

What USP <382> covers

USP <382> sets the functional performance tests for elastomeric components, most commonly vial stoppers, used with injectable medicines. Where USP <381> qualifies the elastomeric material (its physicochemical properties), <382> verifies that the assembled component actually performs its mechanical job in service.

For a vial stopper, the functional attributes generally associated with the chapter include penetrability (the force to push a needle through the stopper), self-sealing capacity (whether the stopper reseals after the needle is withdrawn), and the component’s contribution to keeping the package sealed. Fragmentation, or coring, where a needle cuts loose rubber fragments, has historically been associated with elastomeric closures, and how it is addressed has been revised as the chapter developed. The full breakdown is in our guide to USP <382>. The exact attributes, methods, and acceptance limits are set in the current USP-NF.

What changed when <382> became official

The substantive change is structural: functional suitability now lives in its own chapter, <382>, rather than being mixed into the material chapter, <381>. USP incorporated <382> into the USP-NF in 2020 with a multi-year transition period, and the chapter became official on December 1, 2025. With that, the functionality content that had historically sat within <381> moved to <382>, so the two chapters address different things without overlap.

For drug manufacturers, this clarifies rather than complicates: a component is qualified using both chapters, <381> for whether the rubber compound is suitable and safe, and <382> for whether the component performs reliably. The transition period gave the industry time to align documentation and methods, and now that <382> is official, the current USP-NF text is the controlling reference for both. It is worth confirming the exact current status of specific functional tests, such as the treatment of fragmentation, directly against the current USP-NF, since these details were refined through the chapter’s development.

What it means in practice for closures and seals

Because functional suitability is assessed for the component in its actual packaging system, the vial, the stopper, and the aluminium seal that crimps over the stopper are all part of the picture, not just the rubber on its own. USP <382> applies to the elastomeric closure, but the closure does not act alone.

• The stopper provides the resealing barrier and is the focus of <382>’s functional tests. Its material sits under USP <381>; it is an elastomeric closure, usually a butyl rubber stopper.
• The seal crimps over the stopper and holds it compressed against the glass, which is part of how the assembled package maintains integrity. A poorly applied seal can undermine the very package integrity that functional suitability assumes, which is why vial crimping and seal consistency matter.
• The system view means a stopper qualified with one vial and seal configuration should be re-evaluated if the vial geometry, seal design, or crimp parameters change.

So while <382> is a stopper chapter, the practical takeaway for packaging is that functional suitability is a property of the whole container closure system, and the seal’s correct application is part of preserving it. Container closure integrity itself is addressed under USP <1207>.

How this works in practice at Autofits

USP <382> applies to the elastomeric stopper, which is qualified by the drug manufacturer; Autofits makes the aluminium and aluminium-plastic seals that crimp over that stopper to complete the container closure system. The range includes FlipTop Optima flip-off seals, tear-off and tear-down aluminium seals, and aluminium pilfer-proof (ROPP) caps, in 13, 20, and 32 mm sizes (the full products page lists the range). Dimensional consistency in the seal supports reliable crimping, which holds the stopper in the compression that functional suitability under USP <382> assumes. Autofits produces these seals under an ISO 15378:2017 quality system, alongside ISO 9001:2015 and ISO 14001:2015 certification and a Drug Master File, in a 75,000 sq ft Nashik facility with an ISO Class 8 cleanroom and high-speed visual inspection. The full certification set is on the quality page.

Frequently asked questions

When did USP <382> become official?

USP <382> became official on December 1, 2025. It had been incorporated into the USP-NF in 2020 with a multi-year transition period before becoming the official chapter. The current USP-NF text is the controlling reference for its requirements.

What is the difference between USP <381> and USP <382>?

USP <381> covers the elastomeric component’s material requirements (physicochemical properties), answering whether the rubber compound is suitable and safe. USP <382> covers the component’s functional performance in its system, such as penetrability and self-sealing. The functionality tests that used to sit in <381> were moved to <382>. A component is qualified using both.

Does USP <382> introduce new tests?

USP <382> mainly gives functional suitability its own dedicated chapter rather than introducing a wholly new test regime; much of the functional content moved from <381>. The functional attributes generally include penetrability, self-sealing, and contribution to package integrity. Some details, such as the treatment of fragmentation, were revised as the chapter developed, so the current USP-NF text is the definitive source for the exact tests and limits.

Does USP <382> apply to the aluminium seal?

USP <382> applies to the elastomeric closure (the rubber stopper), not the aluminium seal directly. However, functional suitability, especially self-sealing and package integrity, is evaluated with the closure in its actual container closure system, which includes the aluminium or aluminium-plastic seal crimped over the stopper. The seal’s correct application is part of what lets the assembled package maintain integrity.

What should packaging teams do now that <382> is official?

Treat elastomeric component qualification as a two-part exercise: material under USP <381> and function under USP <382>, both against the current USP-NF text. Because functional suitability is assessed in the actual packaging system, confirm that the stopper, vial, and seal configuration is the one tested, and re-evaluate if any of those components or the crimp parameters change.

Related reading

• USP <382>: elastomeric component functional suitability
• USP <381>: elastomeric components in injectable packaging
• Elastomeric closure: definition
• Vial crimping explained
• USP <1207>: container closure integrity

Sources

• USP-NF: General Chapter <382>, Elastomeric Component Functional Suitability in Parenteral Product Packaging/Delivery Systems (https://www.usp.org/)
• USP-NF: General Chapter <381>, Elastomeric Components in Injectable Pharmaceutical Product Packaging/Delivery Systems (https://www.usp.org/)
• USP-NF: General Chapter <1207>, Package Integrity Evaluation, Sterile Products (https://www.usp.org/)

*Last updated: 2026-06-18. This article is general regulatory information, not legal or compliance advice; confirm current chapter text, methods, and acceptance criteria with USP-NF.*