STORAGE:
Store the flag you want to preserve in a dark place. Bright light, especially sunlight, causes fading and deterioration of fabrics. Avoid very humid places and rooms where temperatures vary a great deal.
Store your flag where you have sufficient access to inspect it for pest or mildew damage at least once a year. Garages, basements, and attics are probably the worst places to store textiles because these risks are high.
The crisp “official†fold is appropriate for a flag in regular use, but prolonged storage will lead to permanent creases. If you don’t have room to store the flag flat, there are some options. One is to use acid-free tissue paper, or clean, unbleached cotton cloth to fill out the folds. Another alternative is to roll the flag on a tube of acid-free material; do not use cardboard or wood, both of which are likely to be acidic.
In fact, it is important to avoid storing your flag in contact with wood. Be sure to line the storage drawer with a polyester film or other inert material, or wrap the rolled-up flag in a cover of unbleached cotton or some other acid-neutral material. Don’t use pesticides or mothballs. They contain chemicals that are harmful to fabrics.
CLEANING:
Minimize washing or cleaning flags or other textiles you want to keep. If your flag is very old, more than 30 years, you should not wash or dry clean it except with the advice of a professional conservator.
The only appropriate cleaning method for old flags is vacuuming gently (on low suction) using a brush attachment covered by a clean piece of cheesecloth. It is best not to contact the flag with a brush that has been used for other cleaning, and the cheesecloth will prevent tears and snags. Vacuum a fabric by gently patting the surface as if you were blotting it.
New flags should be clean when they are stored. Depending on the type of material, the flag can be washed gently by hand using a mild soap.