{"id":7949,"date":"2026-04-27T16:44:25","date_gmt":"2026-04-27T08:44:25","guid":{"rendered":"https:\/\/www.qualitester.com\/?page_id=7949"},"modified":"2026-04-27T16:44:25","modified_gmt":"2026-04-27T08:44:25","slug":"usp-381","status":"publish","type":"page","link":"https:\/\/www.qualitester.com\/uk\/standards\/usp-381\/","title":{"rendered":"USP 381"},"content":{"rendered":"<h1 data-section-id=\"yzzvkq\" data-start=\"386\" data-end=\"460\">USP 381 Elastomeric Closures for Injections &#8211; Functionality Testing<\/h1>\n<p data-start=\"462\" data-end=\"811\">In pharmaceutical packaging, elastomeric closures must ensure <strong data-start=\"524\" data-end=\"582\">container integrity, sterility, and repeated usability<\/strong>. <span class=\"hover:entity-accent entity-underline inline cursor-pointer align-baseline\"><span class=\"whitespace-normal\">USP 381<\/span><\/span> defines strict functionality criteria to verify these properties. This standard focuses on closures intended for needle puncture, emphasizing mechanical performance and sealing reliability.<\/p>\n<p data-start=\"813\" data-end=\"1030\">Manufacturers and quality control teams rely on USP 381 to evaluate three essential characteristics: <strong data-start=\"914\" data-end=\"973\">penetrability, fragmentation, and self-sealing capacity<\/strong>. These tests directly impact drug safety and compliance.<\/p>\n<h2 data-section-id=\"1kacewn\" data-start=\"1037\" data-end=\"1073\">Rubber Stopper Functionality Test<\/h2>\n<p data-start=\"1075\" data-end=\"1325\">The rubber stopper functionality test under USP 381 ensures closures maintain performance throughout their lifecycle. Before testing, samples undergo preparation similar to Solution S treatment and air-drying, ensuring consistency across evaluations.<\/p>\n<p data-start=\"1327\" data-end=\"1365\">The functionality assessment includes:<\/p>\n<ul data-start=\"1367\" data-end=\"1548\">\n<li data-section-id=\"1nbwar0\" data-start=\"1367\" data-end=\"1446\">Controlled puncture using a <strong data-start=\"1397\" data-end=\"1446\">lubricated hypodermic needle (12\u00b0 \u00b1 2\u00b0 bevel)<\/strong><\/li>\n<li data-section-id=\"1ov9t2u\" data-start=\"1447\" data-end=\"1486\">Repeated mechanical stress simulation<\/li>\n<li data-section-id=\"x6it7x\" data-start=\"1487\" data-end=\"1548\">Evaluation of particle generation and sealing performance<\/li>\n<\/ul>\n<p data-start=\"1550\" data-end=\"1689\">These procedures replicate real clinical use conditions, ensuring closures withstand <strong data-start=\"1635\" data-end=\"1688\">multiple punctures without compromising sterility<\/strong>.<\/p>\n<h2 data-section-id=\"1crse5g\" data-start=\"1696\" data-end=\"1742\">USP 381 Elastomeric Closures for Injections<\/h2>\n<p data-start=\"1744\" data-end=\"1905\">USP 381 elastomeric closures for injections define <strong data-start=\"1795\" data-end=\"1831\">quantitative acceptance criteria<\/strong> that laboratories must follow. Each test targets a specific failure risk:<\/p>\n<ul data-start=\"1907\" data-end=\"2054\">\n<li data-section-id=\"prhf39\" data-start=\"1907\" data-end=\"1960\"><strong data-start=\"1909\" data-end=\"1926\">Penetrability<\/strong> \u2192 usability and injection force<\/li>\n<li data-section-id=\"18mm5r8\" data-start=\"1961\" data-end=\"2003\"><strong data-start=\"1963\" data-end=\"1980\">Fragmentation<\/strong> \u2192 contamination risk<\/li>\n<li data-section-id=\"1jbt0gx\" data-start=\"2004\" data-end=\"2054\"><strong data-start=\"2006\" data-end=\"2022\">Self-sealing<\/strong> \u2192 container closure integrity<\/li>\n<\/ul>\n<p data-start=\"2056\" data-end=\"2203\">By aligning with USP 381, manufacturers demonstrate compliance with pharmacopeial requirements and enhance regulatory acceptance in global markets.<\/p>\n<h2 data-section-id=\"152hy1p\" data-start=\"2210\" data-end=\"2250\">Penetrability Test for Rubber Stopper<\/h2>\n<p data-start=\"2252\" data-end=\"2345\">The penetrability test for rubber stopper evaluates the force required to pierce the closure.<\/p>\n<p data-start=\"2347\" data-end=\"2370\"><strong data-start=\"2347\" data-end=\"2370\">Procedure overview:<\/strong><\/p>\n<ul data-start=\"2371\" data-end=\"2529\">\n<li data-section-id=\"gicv2d\" data-start=\"2371\" data-end=\"2417\">Fill 10 vials with water to nominal volume<\/li>\n<li data-section-id=\"1thyxoh\" data-start=\"2418\" data-end=\"2457\">Apply closures and secure with caps<\/li>\n<li data-section-id=\"dloeo1\" data-start=\"2458\" data-end=\"2529\">Pierce each closure with a new needle, perpendicular to the surface<\/li>\n<\/ul>\n<p data-start=\"2531\" data-end=\"2549\"><strong data-start=\"2531\" data-end=\"2547\">Requirement:<\/strong><\/p>\n<ul data-start=\"2550\" data-end=\"2611\">\n<li data-section-id=\"1wwqyqu\" data-start=\"2550\" data-end=\"2611\">The force must not exceed <strong data-start=\"2578\" data-end=\"2586\">10 N<\/strong>, with \u00b10.25 N accuracy<\/li>\n<\/ul>\n<p data-start=\"2613\" data-end=\"2714\">This test ensures operators can safely and consistently puncture the closure without excessive force.<\/p>\n<p data-start=\"2716\" data-end=\"2998\"><strong data-start=\"2716\" data-end=\"2744\">Instrumentation insight:<\/strong><br data-start=\"2744\" data-end=\"2747\" \/>\u0423 \"The <a href=\"https:\/\/www.qualitester.com\/uk\/%d0%bf%d1%80%d0%be%d0%b4%d1%83%d0%ba%d1%82\/medical-needle-puncture-tester\/\" target=\"_blank\" rel=\"noopener\"><strong data-start=\"2751\" data-end=\"2784\">NPT-01 Needle Penetrability Tester<\/strong><\/a> provides precise force measurement, controlled speed, and repeatable positioning. Its <strong data-start=\"2871\" data-end=\"2928\">PLC control and high-resolution displacement accuracy<\/strong> help laboratories meet USP 381 requirements with minimal variability.<\/p>\n<h2 data-section-id=\"19fav6t\" data-start=\"3005\" data-end=\"3043\">Fragmentation Evaluation in USP 381<\/h2>\n<p data-start=\"3045\" data-end=\"3145\">Fragmentation testing measures the risk of <strong data-start=\"3088\" data-end=\"3118\">rubber particle generation<\/strong> during repeated punctures.<\/p>\n<p data-start=\"3147\" data-end=\"3161\"><strong data-start=\"3147\" data-end=\"3161\">Key steps:<\/strong><\/p>\n<ul data-start=\"3162\" data-end=\"3326\">\n<li data-section-id=\"aemzlm\" data-start=\"3162\" data-end=\"3240\">Perform multiple punctures (typically four per closure at different sites)<\/li>\n<li data-section-id=\"1bv7ib\" data-start=\"3241\" data-end=\"3298\">Filter the combined liquid through a \u22640.5 \u03bcm membrane<\/li>\n<li data-section-id=\"nttvaa\" data-start=\"3299\" data-end=\"3326\">Count visible particles<\/li>\n<\/ul>\n<p data-start=\"3328\" data-end=\"3355\"><strong data-start=\"3328\" data-end=\"3353\">Acceptance criterion:<\/strong><\/p>\n<ul data-start=\"3356\" data-end=\"3408\">\n<li data-section-id=\"udyith\" data-start=\"3356\" data-end=\"3408\">No more than <strong data-start=\"3371\" data-end=\"3406\">five visible fragments (&gt;50 \u03bcm)<\/strong><\/li>\n<\/ul>\n<p data-start=\"3410\" data-end=\"3598\">This test is critical because particulate contamination can compromise <strong data-start=\"3481\" data-end=\"3515\">drug safety and patient health<\/strong>. Laboratories often integrate microscopy verification when results are borderline.<\/p>\n<h2 data-section-id=\"12ahjq8\" data-start=\"3605\" data-end=\"3644\">Self Sealing Test for Rubber Stopper<\/h2>\n<p data-start=\"3646\" data-end=\"3757\">The self sealing test for rubber stopper verifies whether closures maintain integrity after repeated punctures.<\/p>\n<p data-start=\"3759\" data-end=\"3784\"><strong data-start=\"3759\" data-end=\"3784\">Procedure highlights:<\/strong><\/p>\n<ul data-start=\"3785\" data-end=\"3955\">\n<li data-section-id=\"1ysvj6v\" data-start=\"3785\" data-end=\"3844\">Pierce each closure <strong data-start=\"3807\" data-end=\"3842\">10 times at different locations<\/strong><\/li>\n<li data-section-id=\"1tlazes\" data-start=\"3845\" data-end=\"3898\">Immerse vials in <strong data-start=\"3864\" data-end=\"3896\">0.1% methylene blue solution<\/strong><\/li>\n<li data-section-id=\"iqe7c4\" data-start=\"3899\" data-end=\"3955\">Apply vacuum (27 kPa reduction) and restore pressure<\/li>\n<\/ul>\n<p data-start=\"3957\" data-end=\"3975\"><strong data-start=\"3957\" data-end=\"3973\">Requirement:<\/strong><\/p>\n<ul data-start=\"3976\" data-end=\"4017\">\n<li data-section-id=\"1nwpnvr\" data-start=\"3976\" data-end=\"4017\">No dye ingress is allowed in any vial<\/li>\n<\/ul>\n<p data-start=\"4019\" data-end=\"4266\"><strong data-start=\"4019\" data-end=\"4040\">Testing solution:<\/strong><br data-start=\"4040\" data-end=\"4043\" \/>\u0423 \"The <a href=\"https:\/\/www.qualitester.com\/uk\/%d0%bf%d1%80%d0%be%d0%b4%d1%83%d0%ba%d1%82\/lt-03-seal-strength-testing-machine\/\" target=\"_blank\" rel=\"noopener\"><strong data-start=\"4047\" data-end=\"4068\">\u0422\u0435\u0447\u0435\u0448\u0443\u043a\u0430\u0447 LT-03<\/strong><\/a> enables controlled vacuum conditions and clear visual detection. Its <strong data-start=\"4138\" data-end=\"4186\">stable vacuum system and transparent chamber<\/strong> allow accurate observation of leakage, aligning closely with USP 381 protocols.<\/p>\n<h2 data-section-id=\"vl9ony\" data-start=\"4273\" data-end=\"4317\">Why USP 381 Matters for Quality Assurance<\/h2>\n<p data-start=\"4319\" data-end=\"4437\">USP 381 provides a <strong data-start=\"4338\" data-end=\"4376\">scientifically validated framework<\/strong> for evaluating elastomeric closures. Its importance lies in:<\/p>\n<ul data-start=\"4439\" data-end=\"4650\">\n<li data-section-id=\"9sqlxx\" data-start=\"4439\" data-end=\"4479\">\u0417\u0430\u0431\u0435\u0437\u043f\u0435\u0447\u0435\u043d\u043d\u044f <strong data-start=\"4450\" data-end=\"4479\">drug sterility and safety<\/strong><\/li>\n<li data-section-id=\"hp6f0p\" data-start=\"4480\" data-end=\"4539\">\u041f\u0456\u0434\u0442\u0440\u0438\u043c\u043a\u0430 <strong data-start=\"4493\" data-end=\"4539\">regulatory compliance (FDA, pharmacopeias)<\/strong><\/li>\n<li data-section-id=\"1xbl91n\" data-start=\"4540\" data-end=\"4598\">Reducing risks of <strong data-start=\"4560\" data-end=\"4598\">particle contamination and leakage<\/strong><\/li>\n<li data-section-id=\"1bunt9z\" data-start=\"4599\" data-end=\"4650\">Enhancing <strong data-start=\"4611\" data-end=\"4650\">product reliability in clinical use<\/strong><\/li>\n<\/ul>\n<p data-start=\"4652\" data-end=\"4762\">Companies that implement USP 381 testing protocols strengthen both <strong data-start=\"4719\" data-end=\"4761\">product quality and market credibility<\/strong>.<\/p>\n<h2 data-section-id=\"1r8frcv\" data-start=\"4769\" data-end=\"4798\">\u041f\u043e\u0448\u0438\u0440\u0435\u043d\u0456 \u0437\u0430\u043f\u0438\u0442\u0430\u043d\u043d\u044f<\/h2>\n<p data-start=\"4800\" data-end=\"4963\"><strong data-start=\"4800\" data-end=\"4838\">1. What is the purpose of USP 381?<\/strong><br data-start=\"4838\" data-end=\"4841\" \/><a href=\"https:\/\/www.uspnf.com\/sites\/default\/files\/usp_pdf\/EN\/USPNF\/revisions\/381_elastomeric_closure_for_injections_rb_notice.pdf\" target=\"_blank\" rel=\"noopener nofollow\">USP 381<\/a> defines functionality and physicochemical requirements for elastomeric closures used in injectable drug packaging.<\/p>\n<p data-start=\"4965\" data-end=\"5123\"><strong data-start=\"4965\" data-end=\"5003\">2. Why is penetrability important?<\/strong><br data-start=\"5003\" data-end=\"5006\" \/>It ensures healthcare professionals can puncture closures easily without excessive force, reducing operational risks.<\/p>\n<p data-start=\"5125\" data-end=\"5285\"><strong data-start=\"5125\" data-end=\"5174\">3. How does fragmentation affect drug safety?<\/strong><br data-start=\"5174\" data-end=\"5177\" \/>Rubber particles may contaminate injectable drugs, posing risks to patients and violating regulatory limits.<\/p>\n<p data-start=\"5287\" data-end=\"5439\"><strong data-start=\"5287\" data-end=\"5333\">4. When is the self-sealing test required?<\/strong><br data-start=\"5333\" data-end=\"5336\" \/>It applies mainly to <strong data-start=\"5357\" data-end=\"5385\">multiple-dose containers<\/strong>, where closures must reseal after repeated punctures.<\/p>\n<p data-start=\"5441\" data-end=\"5639\"><strong data-start=\"5441\" data-end=\"5498\">5. What equipment is recommended for USP 381 testing?<\/strong><br data-start=\"5498\" data-end=\"5501\" \/>Precision instruments like the <strong data-start=\"5532\" data-end=\"5565\">NPT-01 \u0422\u0435\u0441\u0442\u0435\u0440 \u0434\u043b\u044f \u043f\u0440\u043e\u043a\u043e\u043b\u0443 \u0433\u043e\u043b\u043a\u043e\u044e<\/strong> \u0456 <strong data-start=\"5570\" data-end=\"5591\">\u0422\u0435\u0447\u0435\u0448\u0443\u043a\u0430\u0447 LT-03<\/strong> provide reliable and compliant testing results.<\/p>","protected":false},"excerpt":{"rendered":"<p>USP 381 Elastomeric Closures for Injections &#8211; Functionality Testing In pharmaceutical packaging, elastomeric closures must ensure container integrity, sterility, and repeated usability. USP 381 defines strict functionality criteria to verify these properties. This standard focuses on closures intended for needle puncture, emphasizing mechanical performance and sealing reliability. Manufacturers and quality control teams rely on USP &hellip;<\/p>\n<p class=\"read-more\"> <a class=\"\" href=\"https:\/\/www.qualitester.com\/uk\/standards\/usp-381\/\"> <span class=\"screen-reader-text\">USP 381<\/span> \u0414\u0435\u0442\u0430\u043b\u044c\u043d\u0456\u0448\u0435 \"<\/a><\/p>","protected":false},"author":4,"featured_media":7950,"parent":4948,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"site-sidebar-layout":"default","site-content-layout":"default","ast-global-header-display":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"disabled","footer-sml-layout":"","theme-transparent-header-meta":"default","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","footnotes":""},"class_list":["post-7949","page","type-page","status-publish","has-post-thumbnail","hentry"],"_links":{"self":[{"href":"https:\/\/www.qualitester.com\/uk\/wp-json\/wp\/v2\/pages\/7949","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.qualitester.com\/uk\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.qualitester.com\/uk\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.qualitester.com\/uk\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/www.qualitester.com\/uk\/wp-json\/wp\/v2\/comments?post=7949"}],"version-history":[{"count":1,"href":"https:\/\/www.qualitester.com\/uk\/wp-json\/wp\/v2\/pages\/7949\/revisions"}],"predecessor-version":[{"id":7951,"href":"https:\/\/www.qualitester.com\/uk\/wp-json\/wp\/v2\/pages\/7949\/revisions\/7951"}],"up":[{"embeddable":true,"href":"https:\/\/www.qualitester.com\/uk\/wp-json\/wp\/v2\/pages\/4948"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.qualitester.com\/uk\/wp-json\/wp\/v2\/media\/7950"}],"wp:attachment":[{"href":"https:\/\/www.qualitester.com\/uk\/wp-json\/wp\/v2\/media?parent=7949"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}