This page is about General Salvage Techniques.
Salvage techniques are arranged by types of collections on the rim of the wheel; apply them to stabilize and dry collections.
- Contact a conservator as soon as possible.
- Work on high priority collection areas first.
- In general, freeze items that cannot dry within 48 hours. Consult a conservator: metal, plate glass, some photographs and furniture may be exceptions to freezing.
Air-Drying. Use a cool, low-humidity area with good air circulation. Place absorbent material (see interleaving) under objects; replace it when wet. If possible, air dry material on plastic racks (commercial bread trays or rust-proof screens) to increase evaporation. Exposure to light may reduce threat of mold, but prolonged sunlight can cause fading.
Interleaving. Use blotter paper, uninked newsprint, paper towels, or waxed or freezer paper to keep items from sticking together and prevent dye transfer or running.
Freezing. If objects cannot be dried within 48 hours, freeze them until action can be taken. Freezing stabilizes collections for months; it stops mold growth, ink running, dye transfer and swelling. A sub-zero commercial freezer is best, but a home freezer works. A refrigerated truck keeps materials cool enough to slow mold growth.
On-Site Dehumidification. Super-dry air is pumped into the building and moist air drawn out. A useful method for damp library and archival collections in place; may be used in modern buildings to dry carpeting, wallboard and furnishings. Do not use for historic structures of wood or plaster or most museum collections.
Rinsing. Rinse dirty or muddy items under a gentle stream of clean running water or gently agitate in containers filled with water. Do not scrub; it drives dirt in deeper. Use a sponge/soft cloth to blot off mud and debris.
Vacuum Drying. Also called "thermal drying." Items are dried in a vacuum chamber, often at temperatures above 100° F. Caution: this method accelerates aging and causes damage to many materials: animal skins (leather, vellum), film media. Widely available; slower than vacuum freeze-drying, but less expensive.
Vacuum Freeze-Drying. Items are dried in a vacuum chamber at below-freezing temperatures to minimize swelling and distortion. Generally provides the most satisfactory results; recommended for historic collecting materials and glossy papers. A commercial service available throughout the U.S.
View the Emergency Response Action Steps
© 1997, Heritage Preservation, Inc.
This information is from the Emergency Response and Salvage Wheel, a sliding chart designed for archives, libraries, and museums. It is also a useful tool for home or business and is available in English and Spanish versions. The Wheel was produced by the Heritage Emergency National Task Force, a public-private partnership sponsored by FEMA and Heritage Preservation. For further information or to order the Wheel, please call toll-free 1-888-979-2233.