Did you ever wonder how to care for your treasured possessions; have questions about how to frame something or about acid-free paper or what is the best way to dust? Here are some general guidelines. These recommendations reflect optimal practice for storage. Do not be discouraged if you cannot do it all. Even if you can only do some of the recommendations, that is still better than nothing and should go a long way to preserving your treasures long term.
Start with the Basics
Light, humidity, and temperature are critical in the preservation of objects, so creating and sustaining a stable environment is the first step in preserving any item. Light, both artificial and ultraviolet (daylight), over time causes fading of the colors of the fibers and will eventually damage the fibers themselves. Humidity and temperature are important to keep in check as mold and mildew, being microorganisms that are ever present in the air, under certain conditions will grow and develop spores feeding on nutrition taken from objects causing
accelerated deterioration and staining.
- Use blinds, shades or curtains to protect objects from bright or direct sunlight and move particularly sensitive objects (textiles, books, paper, watercolors, and organic materials i.e. leather) to dimmer locations (the amount of damage an object sustains varies depending on the intensity and the duration of exposure, and the lightfastness of the material).
- Keep artificial light at a reasonable distance to prevent heat damage and avoid fluorescent lights or sources with a significant ultraviolet component.
- Keep the relative humidity between 45 and 55 percent and the temperature at 72 degrees Fahrenheit or less.
- Change air filters in the HVAC system regularly to reduce dust.
- Place insect sticky traps in collection areas to monitor for pest activity and use vendors with training in integrated pest management (IPM) to address any problems.
Dust is inherently damaging as well as unsightly. It is abrasive, absorbs moisture and pollutants that can cause deterioration and corrosion, attracts insects, and encourages mold growth. Good air filtration is our first line of defense, but careful, regular dusting and vacuuming is a critical part of preventive conservation for the collection.
Dust stable surfaces with a non-abrasive cotton or synthetic dust cloth that will hold dust without leaving any residue on the object. Test any lint free cloth or product you might use on a windowpane and observe whether it holds the dust without causing any change in the glass such as an oily sheen. Avoid products that contain silicone. Do not dust surfaces with flaking paint or gilding. The same cloths can be used with mops on uncarpeted floors and wood moldings. Do not use a damp cloth on gilt surfaces as many gilt frames use a water soluble adhesive.
Dust complex or fragile surfaces such as intricate ceramics or gilded frames with a very soft long bristle brush moving dislodged dust toward a dust cloth or vacuum nozzle.
Use vacuum cleaners with HEPA (High Efficiency Particulate Air) filters and adjustable suction for carpets, upholstery and drapes. To protect the item and avoid catching or abrading the surface use a piece of nylon mesh secured around the nozzle of an appropriate vacuum attachment. Using the vacuum at a low speed hold the vacuum attachment just above the surface of the item and move it gently across the surface. Books should be held firmly closed for cleaning to prevent infiltration of and contamination from debris.
Books, Manuscripts and Ephemera
Identifying the material an item is composed of will help in determining and understanding how to care for the item. Historically paper was made from cotton linters, often referred to as rag paper. Wood pulp paper products were introduced in the mid-19th century. These wood pulp papers quickly become acidic and contain high levels of lignin. Lignin is responsible for newspaper print yellowing with age. Newer paper products (post 1990s) are treated with buffers to produce acid free buffer paper. The best archival paper is made from 100 percent cotton linters (not wood pulp). These papers can be treated with various buffers and agents that are designed to enhance or add specific qualities to the paper, i.e. pH level, fire retardant, and waterproofing, that are deemed desirable for their end use.
- Shelve books carefully using bookends to keep them firmly upright. Shelve large and fragile books, especially scrapbooks and photo albums, flat.
- Do not oil or dress leather bindings since this practice contributes to deterioration.
- Use a cradle, wedge or some other support for open books being read or displayed to prevent damaging the binding by forcing the open book flat on a table.
- Store manuscripts and ephemera in acid-free enclosures using archival quality paper and/or plastics (uncoated polyester, polypropylene or polyethylene).
- Avoid placing bookcases against poorly insulated exterior walls that can trap pockets of high humidity.
- Handle photographs wearing white cotton gloves to avoid leaving corrosive fingerprints on the image.
- Store or frame photographs in acid-free enclosures using archival quality paper and/or plastics (uncoated polyester, polypropylene or polyethylene).
- Store large photographs, images on brittle mounts and fragile albums flat in acid-free boxes.
- Store albums in custom size book boxes when possible.
- Wear white cotton gloves when handling to avoid leaving corrosive fingerprints.
- Protect textiles from dust since washing can be problematic. If they are soiled, vacuum gently as described above.
- If an item has evidence of mold or mildew they should be quarantined (removed from other items) to prevent contaminating other objects. Air out and then carefully vacuum the item. If proper air circulation is maintained and relative humidity is kept 45-55 percent with a temperature of 68-72 degrees Fahrenheit, mold and mildew should not occur. When in doubt, consult a conservator.
- Store textiles using acid-free tissue, clean 100 percent cotton sheets (unbleached recommended) and acid-free boxes. Alkaline (buffered) acid-free tissue remains acid-free for a longer period and is used for cotton and linens. Unbuffered (none alkaline) acid-free tissue is used for silk and woolens.
- Store textiles horizontally using boxes made of acid-free material. Line the box with padding and place the item in the box to minimize folds.
- Avoid creases by making the folds loose and using crumpled tissue between the folds. Sharp surfaces on an item must be padded.
- Ironing should be avoided. Extra padding may smooth out folds, but textiles should never be forced.
- For larger textiles, like quilts, avoid creasing by rolling the textiles around an acid-free tube using acid-free tissue as padding.
- Use acid-free materials and spacers to separate textiles from the glass when having textiles mounted and framed.
- Handle metal objects wearing white cotton or latex gloves to avoid leaving corrosive fingerprints.
- To prevent corrosion, keep the humidity as low as possible and dust regularly with a soft cotton cloth.
- Store metal objects on lightly padded shelves, surround unstable or top-heavy objects with bean bags to improve stability, and interleave any stacked items with cotton flannel to prevent scratches and abrasion.
- Since metals are particularly sensitive to pollution and off gassing from wood, paint and adhesives, store them in acid-free boxes and use only archival quality paper and/or plastics (uncoated polyester, polypropylene or polyethylene). Store silver in bags made from Pacific silver cloth which contains a tarnish inhibitor.
- Gold, silver, copper and its alloys, and pewter can be gently cleaned with ethyl alcohol on a cotton swab if dusting does not suffice.
Ceramics and Glass
- Avoid using gloves on most ceramics and glass as it reduces ones grip. White cotton gloves should be used to avoid leaving corrosive fingerprints when handling ceramics with a luster or metallic glaze that use metal oxides to create the finishes which are susceptible to corrosion.
- Store fragile objects on lightly padded shelves, surround unstable or top-heavy objects with bean bags to improve stability, and interweave any stacked items with cotton flannel to prevent abrasion.
- Inspect the surface for lifting glaze, cracks or past repairs before cleaning. If the surface is stable, use a lightly moistened cotton swab or cloth to wipe the surface and dry immediately.
- Do not soak ceramics to try and remove stains since some ceramic bodies are porous and can be seriously damaged.
Works on Paper (prints, drawings, watercolors)
- Use acid-free materials and spacers to separate the paper from the glass when having objects mounted and framed.
- Avoid hanging objects on poorly insulated outside walls, over radiators, or above fireplaces since these areas experience wide fluctuations in temperature and humidity.
- Store unframed objects in mats or acid free folders and boxes.
- Avoid hanging paintings on poorly insulated outside walls, over radiators, or above fireplaces since these areas experience wide fluctuations in temperature and humidity
- If careful examination reveals the surface of the painting is stable (no flaking or areas of distorted or insecure paint), dust it lightly with a soft long bristle brush.
- Make sure the frame, hanging hardware and wires are securely attached and in good condition.
- Secure a piece of acid-free board to the back of the stretcher with screws to protect the back of the canvas from grime, debris and physical damage.