When storing books (antique or otherwise) it’s important to put them in an atmosphere that reduces the chance for mold growth. The following are some tips to help prevent mold growth on books in storage. If, however, you find that mold has grown on your books in storage there are ways to clean up the books and stop the mold from returning.
What is Mold?
Mold is a fungus grown in spores that can be found on organic materials like paper, books, cloth, and leather. Mold is dormant, usually, unless humidity exceeds 70% and or temperatures exceed 65°F.
Inactive mold is often white, dry, and powdery; active mold is usually green, orange, purple or black. If the mold is in very humid or damp conditions, it may be “slimy”, otherwise its usually “fuzzy” looking. Mold can spread easily on people, pets, and through the air.
Mold can be prevented by keeping books in a low humidity (<70%), consistently cool, (65°F) area with good air circulation. You can’t prevent mold spores from being in the room where you’re books are, mold spores are everywhere. You can, however, prevent mold spores from becoming active by maintaining the right conditions.
Salvage of items attacked by mold:
When dealing with mold, remember there can be health risks, especially for people with respiratory problems, so proper protective action should be taken before handling the items affected. Work outside or in a well ventilated area whenever possible and wear rubber gloves, eye protection, and a mask to protect yourself. Any clothing worn should be washed in hot water only. Any work surfaces should be covered in clean unprinted paper, to be disposed of as soon as the salvage project is complete.
Although a few types of mold are toxic; many can cause skin irritation or an allergic reaction. If you are concerned about the toxicity of the mold, call a local hospital or mold Remediation Company to find a mycologist (mold specialist).
If you have a large quantity of books in storage to salvage or you don’t have the time to dedicate to the project, the affected books can be frozen until you are available.
Segregate the mold affected items to a clean area with low humidity below 45%RH. The books can be moved in sealed plastic bags to prevent the mold from spreading but should not be stored in the bags long term.
The books will then need to be dried out either by increasing air circulation (don’t blow fans directly at the books because this can spread the mold and damage the books) or drying outside in the sun in short interims (30-60 minutes or less at one time). Clean newsprint or acid free paper can be placed between pages to absorb moisture and if the books are sturdy enough they can be stood up and the pages fanned out. Just don’t turn up the heat to dry the books, this will speed up the mold growth.
Once the books in storage are dry and the mold is inactive, they can be cleaned up. A small soft brush can be used to wipe away the dried mold residue. Cleaning products like bleach can damage books so they should not be used. Sometimes with antique books alcohol on a cotton swab rolled across the mold can help, but salvage of valuable antique books should require consultation of a professional conservator.
When the books are cleaned up, before you return them to storage, make sure you clean and disinfect the storage areas. Also, make sure that the conditions are acceptable for storing books. Fix any problems that exist and verify that air circulation is good, the temperature is consistent and cool <65°F, and the relative humidity is low <70RH. If you don’t rectify problem storage conditions, the mold will return.
Always monitor conditions in a book storage area often so adjustments can be made if necessary. For professional help, you can get a free referral of a conservator from the American Institute for conservation of Historic and Artistic Works.American Institute for Conservation of Historic and Artistic Works. 1717 K. Street NW, Suite 301, Washington D.C 20036, Phone # 202-452-9545, Fax: 202-452-9328