An inexpensive and safe method of storing prints is to put them loose and flat in a box made of acid-free cardboard, chemically inert plastic or steel with a baked enamel finish. If the photographs are interleaved to prevent them from sticking to each other, the paper should be acid-free. Never keep a photograph that has begun to deteriorate in a box with photographs that are in good condition. Keep the prints in a cool, dark, and dry palace where the temperature and humidity level will not fluctuate. Store black and white negatives separately from color negatives.
Store slides separately from all negatives.
These types should not be stored together. Glass plate negatives are easy to identify because the negative is on glass. The surest test for nitrate film is to take a very small cutting from the edge of the negative, and, holding it with a tweezers over a sink, set fire to it. If it burns quickly with a smell similar to burning hair, it is nitrate base film. If it burns slowly or not at all, it is safety film.