It is also advisable not to remove their envelopes from them, or to put them on dirty, rough or hot surfaces. Improper conservation of information records can cause yellow stains which, over time, destroy the film emulsion. Such stains usually occur when the film is exposed to pollution from industrial gases or to air that does not circulate inside the room. Relative humidity and temperature are the factors that have the greatest impact on conservation of photographic materials. Inadequate conservation accelerates the aging of these materials.
Photographic materials based on photosensitivity are very sensitive to environmental conditions.
Therefore it is necessary to take all climatological measures to extend their life. For example, high relative humidity can in a short time destroy photographic records stored on film. Systematic control of relative humidity is essential for the durability of these media. High relative humidity accelerates discoloration, yellowing, mold growth and rust formation. But the most important thing is to ensure that the climatological indicators in the conservation room are stable and undergo no cyclical changes.