As nitrate film deteriorates it produces nitric acid fumes which will damage other records stored in the vicinity and can cause health problems for staff working with the material. Cellulose acetate film is also known as safety film because it was developed to avoid the high risks associated with nitrate film. It was widely used until the 1970s and is still commonly used in some photographic applications. Once acetate film starts to degrade it gives off acetic acid vapour, a type of deterioration commonly known as vinegar syndrome . As the deterioration progresses the base material shrinks and the emulsion layer starts to warp and wrinkle.
Acetate film includes both diacetate and triacetate bases.
Triacetate is relatively more stable than diacetate, but it too may develop vinegar syndrome as it ages. Acetate film was produced after the 1940s. Handle with care. Lint-free cotton gloves should be used at all times when handling photographic material. Labels and identification stamps should never be applied directly to photographic material.