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 All volumes from the Book Hospital are placed in cases to preserve them and minimize any further deterioration. There are four types of cases: Prefabricated cases, CMI cases, phase boxes, and envelopes. View more information on enclosures on the Books End-Processing Manual.

• Prefabricated cases, called prefabs for short, are archival pre-made cases purchased from a vendor with stiff covers, cloth spines, and inner pockets.
• CMI cases are manufactured by a vendor (Custom Manufacturing, Inc.) that creates custom archival clamshell cases easily assembled when delivered to Houghton Library. They are made of archival corrugated tan board that completely encloses the books.
• Phase boxes are cases produced at Widener Library’s Preservation Services. They are custom, extra sturdy, archival blue boxes with string tie closures.
• Tyvek envelopes are usually used for books not needing preservation but part of a multi-volume title. Visit Books End Processing Manual wiki for instructions.

Enclosures Assessment

Each book is assessed for the case that best meets its preservation needs. There are some general rules to assess the appropriate casing needed.

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