Fragile or slightly damaged items without exceptional artifactual or research value can be enclosed in mylar or acid-free paper sleeves. Especially fragile or valuable items, including some special formats, may require matting. Mats are cut by the Conservation Laboratory.
Mylar or acid-free bond paper sleeves can also be used to isolate clippings and photos from adjacent documents, where the nature of the materials can cause harmful chemical reactions and interaction (e.g. clippings can stain adjacent documents).