Putting It Into Practice

Storing Media Collections

Microforms

Microfilm produced between the 1930s and the 1970s is likely to be on acetate base and thus may suffer from "vinegar syndrome," so called because of the distinctive odor given off in the deterioration process. From the mid-1970s onward, microfilm has been produced on a polyester film base. Very early microfilm on a nitrate base could be encountered, but this is highly unlikely.

General storage recommendations for microforms (roll microfilm and microfiche) are similar to those for motion picture film. All enclosures should pass the Photographic Activity Test to determine whether they contain damaging chemicals or additives. Paper or plastic enclosures are acceptable. Paper enclosures should be lignin-free and buffered or neutral; safe plastics are polyester, polyethylene, and polypropylene (not PVC or vinyl).

Microfilm reels should be boxed individually, with the film held in position by a preservation-quality paper tag fastened with a string and button tie. Do not secure the reels with rubber bands, because they contain residual sulphur and deteriorate over time. Master negatives of microfilm should be stored in a preservation-quality box in an offsite storage area with a controlled climate. Microfilm should be stored in steel filing cabinets, but, if the film must be stored on shelves, inert plastic containers can be used.

Microfiche should be sleeved individually with the emulsion side away from the interior enclosure edges; this prevents abrasion and damage from adhesives. Store microfiche enclosures in steel cabinets, and ensure that the enclosures fit into the drawers without buckling. Use pH-neutral drawer dividers to keep microfiche from curling, and compress the fiche as little as possible in the drawer. Design your filing system to minimize handling of fiche.