Hello again, I was hoping to get some additional information from you, but didn't want you to go without an answer, so I will send your answer, now.
You can clean the mildew with a commercial mildew cleaner, sprayed on a cloth or paper towel, but these usually contain bleach, which may discolor the inside of your safe, so you can also use some distilled white vinegar on a cloth or paper towel or a baking soda solution of 1/4 cup baking soda to 1 quart warm water and clean the inside of all surfaces of the safe. Then, take a clean cloth with clear water and wipe out the safe to fully rinse. Dry it with paper towel and leave it open for at least an hour, to make sure all areas are dry. If the vinegar leaves an undesirable smell, fill a small bowl with coffee grounds and place in the safe with the door closed. This will absorb the odor. Keep it in there for about 2 hours.
Store your jewelry and important papers in airtight containers, so they are not affected by any humidity that may enter the safe.
If your safe has a rubber gasket around the door, check for any tears or rubbed away areas, as that could be how the moisture is getting in. Also, store your safe in a cool, dry area of the house.
To prevent moisture from building up inside the safe, use a desiccant like 'DampRid.' These containers of varying sizes contain salt-based material that draws in and absorbs excess moisture in the environment. They can be found in home improvement stores, hardware stores, Walmart, Target, etc. or be ordered online. Choose the size best for the size of your safe and place the container in the back corner of the safe. Every week or two check to see how much water it has accumulated; spill it out, allow the crystals to dry and reuse. Here is more information:
You should also leave the door to your safe open, to air out, for 20 minutes, every two weeks.
You can order additional shelves and other accessories directly from the manufacturer. If you don't have their contact information, please let me know the maker of your safe and I will research this information for you.
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