EncapsulationEncapsulation is the process of enclosing a fragile paper item between two sheets of archival quality polyester film and then sealing to provide protection from handling and ease of viewing. Mylar is a trade name for the type of film commonly used. This method is used for storage of items because the film is transparent, inert and stable. What should I encapsulate? It would be an expensive undertaking to encapsulate all paper documents. Determine the relative importance of the document itself. If it just holds historical information that you want to preserve it may be more cost-effective to copy the document onto archival paper and keep that instead. The types of items suitable for encapsulation may be fragile documents, some photographic prints, certificates, small textiles or other paper-based records. Once encapsulated, photographs need to be stored upright in a file or folder so that there is no weight pressing the polyester film against the photographic emulsion. Some items may not be suitable for encapsulation. These include drawings in charcoal or pastels, water-colour works or pencil based writing. Residues can come off on the electrostatic polyester so assess the risk to minimize loss or destruction of information. Creating criteria for encapsulation Ask yourself the following questions to determine whether an item may benefit from encapsulation: Does the document need greater physical support for viewing and storage? Can the document be handled without fear of breaking or tearing? Does the document require extra protection from elements such as heat, moisture, light or other risks? Some inks will continue to fade despite encapsulation. If you have an important document that needs to be transported on a regular basis it may be worth encapsulating it in a pre-manufactured Mylar envelope which is permanently sealed on two sides. This makes it easier to insert and remove the document and will minimize potential damage. Encapsulation Process The item is placed between two sheets of film which are then adhered at the edges using archival double-sided tape if you have it and are competent at handling it. For air circulation and access one side should be left open. A cheaper and easily accessible alternative would be to use large stitching on a sewing machine to seal the edges leaving small openings at diagonally opposite corners. A good rule of thumb is to leave a minimum of 2-3cm from edge to stitching and make the enclosure 4-5cm longer than the object being enclosed. The document or photograph can be removed at a future date if necessary as the film is not attached to the item. Encapsulation does not slow down the process of deterioration nor does it offer any UV protection. In fact, in the case of highly acidic items, encapsulation may speed up the rate of deterioration due to reduced air circulation. The item should be assessed for its relative importance and its physical properties. If suitable, encapsulation can be a good method of providing protection for items that could not otherwise be handled safely. References and further reading: WA Museum, Gilroy and Godfrey (eds), Conservation and Care of Collections Australian Institute for the Conservation of Cultural Material (AICCM) ReCollections Canadian Conservation Institute, Encapsulation – CCI Notes 11/10