Paste adhesives absorb moisture and facilitate fungus growth. Maintain a relative humidity between 30 and 50 percent. A dehumidifier or air conditioner will help to maintain the proper environment for storage. Desiccants, such as silica gel, can reduce the relative humidity too much. We do not recommend using desiccants for long-term keeping, but you can use them to dry film and prints before storage.
Occasional projection helps to keep slides dry and free form fungus.
Remove slides form cardboard or glass mounts before you clean them. Clean the film and glass mounts and place them on a piece of window glass to air dry. To accelerate drying, warm the window glass by mounting it a few inches above a low-wattage light bulb. After approximately 10 minutes, you can remount the film in clean glass mounts or new cardboard mounts. Wear clean cotton gloves to avoid getting fingerprints on the film.