Vial Closure and Packaging

In the early stages of product development, vials are typically filled manually, and stoppers are partially inserted by hand, prior to freezedrying. On a production scale, these processes are automated and line trials must be carried out to ensure that appropriate adjustment can be made to allow both vials and stoppers to move freely along the lines without incident and for stoppers to be accurately and reproducibly inserted prior to loading. The design of reliable and effective stoppering devices and mechanisms is of the utmost importance and this aspect has been treated in several monographs. 

One such design feature is the blowback . This term refers to part of the vial neck design with two purposes  

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