There has often been confusion over the meaning and implications of the word ‘archival’. A helpful perspective has been provided by ANSI which has stated that archival films are those suitable for the preservation of records having permanent value.
ANSI also recognises that the phrase ‘having permanent value’ is not equivalent to any finite number of years. ANSI recognises only silver images on an acetate or polyester base as archival. Therefore, any other photographic material must have a stability equal to, or better than, silver safety film before it can be considered archival by this definition.
ANSI distinguishes between archival, long term and medium term film. By archival film it means a high quality photographic film which is suitable for permanent preservation when kept under archival storage conditions. Essentially, no change in the opacity of the film is allowed, and the material must be capable of remaining in its original condition for a minimum of one hundred years. Long term and medium term films are those with a useful life of one hundred years and ten years respectively, assuming the former is kept under archival storage conditions, and the latter under medium term storage conditions (less stringent than archival conditions). It is important to keep in mind that no material is permanent – no material will last forever. Through duplication, the content of unstable film and tape can be transferred to newer carriers and thus be preserved for a long time. The time frame must be considered in centuries, not decades.
Bowser, E. and Kuiper, J., Eds. 1991, FIAF Handbook for Film Archives, 2nd Edition, Federation Internationale des Archives du Film, FIAF, Brussels, Belgium