Elastomeric Closures

To determine the sterility of sterile product packaging, we conduct testing on elastomeric closures. As directed by the USP and EP, elastomeric closures are made of materials obtained by vulcanization (cross-linking) polymerization, poly-addition or poly-condensation of macromolecular organic substances (elastomers). Closure formulations contain natural or synthetic elastomers and inorganic and organic additives to aid or control vulcanization, impart physical and chemical properties or color or stabilize the closure formulation.

The testing as outlined applies to closures formulated with natural or synthetic elastomeric substances. Under specific EP test procedures, closures made from silicone elastomer require a separate and distinct test regimen. The tests may be performed on uncoated or non-laminated closures of the same elastomeric compound. The functionality tests apply to and are to be performed using the entire laminated or coated elastomeric closure. Biological tests apply to both the lamination or coating material and to the base elastomer. Biological tests may be performed on the coating separately from the base elastomer, or on the coated closure itself.

For all the tests, we document the closure being tested — including a full description of the elastomer, and any lubrication, coating, laminations or treatments applied — and we ensure you meet appropriate test limits for Type I and Type II elastomeric closures.

We conduct the following elastomeric test procedures:

• USP/NF Section <381> Elastomeric Closures
• EP 3.2.9 Rubber Closures (Elastomeric)
• EP 3.1.9 Silicone Elastomer – specific to closures made from silicone