For the container sample, testing under USP <671> is specific to moisture transmission rate (MVTR), typically at 40⁰C, 75% rh and spectral transmission in the region of 290nm - 450nm.
Depending on the container type – Plastic Bottle with Closure, Blister Card, Single Unit Dose System – specific moisture transmission test procedures are performed. Some transmission rate tests provide a specific pass/fail specification, while other tests are for benchmark information only.
Spectral transmission is measured using a Perkin Elmer Lambda 650 spectrophotometer with a 150mm integrating sphere which is capable of measuring and recording light transmitted in diffused as well as parallel rays.
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