Long Term Collection Care
TEMPERATURE AND HUMIDITY
Two of the most important considerations for the preservation of an art collection are the temperature and humidity of the environment where they are stored and displayed. Rapid fluctuations in either variable can cause items to expand and contract, destabilizing support structures. Conversely, consistent temperature and humidity levels can help preserve your collection for generations to come. Keeping humidity within a moderate range can help to prevent mold growth and deter insect infestations, while cooler temperatures can minimize the process of aging and deterioration. With that in mind, the following guidelines area a recommended starting point for establishing a proper environment for a collection:
Many types of art respond well to relative humidity levels of between 40 and 60 percent, and temperatures of between 55 and 75 degrees Fahrenheit. These average temperatures are maintained by most museums that house art in a variety of media but are not appropriate for all collections. For example, some photographic prints, negatives and slides (especially acetate and nitrate plastics and glass plate negatives) begin to deteriorate with a relative humidity above 30%; whereas, other papers, parchment or leather items may be taxed at such a low humidity. Many different ratios of temperature and humidity have been experimented with for the storage of sensitive materials. If your collection contains sensitive materials, it is best to consult a conservator with expertise in storage issues.
Many thermostats can be imprecise, you may want to consider installing a compact digital thermohygrometer in areas where art is stored or displayed.
A dehumidifier may be necessary in damp areas, especially during summer months.
An evaporative humidifier may be necessary during the winter and in dry climates.
LOCATION
When planning to display art, choice of location is a key factor in minimizing damage caused by climatic changes, light exposure and accidental injury.
When planning to display art, choice of location is a key factor in minimizing damage caused by climatic changes, light exposure and accidental injury.
In general, display items on interior dividing walls rather than on outer perimeter walls that can experience greater climatic variations. If art is to be installed on exterior walls, placing rubber spacers on the back of the frame can allow air to circulate and minimize harm.
Though the hearth may be a tempting focal point of a room, the vicinity of a fire place is often exposed to elevated temperatures, soot, and rapidly fluctuating humidity levels. Heating and cooling vents should be avoided for the same reasons.
Artwork should never be hung in bathrooms, below pipes or near any exposed water sources.
Display of three-dimensional and framed art in high-traffic areas can invite accidental damage. Items in hallways and dining rooms, in particular, should be hung high enough to avoid impact with handbags, chair backs, or doors.
LIGHT
Controlling the amount of light art is exposed to is also critical to the long-term preservation of an art collection. Damage from light can cause deep, irreversible damage to art. It is particularly harmful to works of art on paper, such as photographs, water colors, pieces with colored inks and any type of negative. Light damage is also cumulative and the subtle changes that occur may not be immediately detectable. UV exposure may manifest itself as brittleness, darkening, bleaching, yellowing, general fading or the change of only certain colors.
Controlling the amount of light art is exposed to is also critical to the long-term preservation of an art collection. Damage from light can cause deep, irreversible damage to art. It is particularly harmful to works of art on paper, such as photographs, water colors, pieces with colored inks and any type of negative. Light damage is also cumulative and the subtle changes that occur may not be immediately detectable. UV exposure may manifest itself as brittleness, darkening, bleaching, yellowing, general fading or the change of only certain colors.
Here are some general guidelines that may be helpful:
- Artwork should always be kept away from direct light, whether from sunlight or artificial sources.
- Picture lights mounted to frames should be avoided. They can create, "hot spots." They can also cause damage to the work if they fall or break.
- Fluorescent light and sunlight contain high levels of UV radiation.
- Keep curtains or shades drawn and lights off when the room is not in use.
- UV protective film can be installed on windows where necessary.
- Museums rotate pieces every three to six months. Try giving art work on display a break: put it in storage in exchange for something that has not been displayed in a while.
- The eye can be deceiving and should not be trusted with measurement of light. In the United States, the illumination an object receives is measured in foot-candles. Foot candles of light can be measured in several ways. A handheld light meter, such as one might use when measuring light for a photographic exposure, can be used to measure light falling on your art work as well. This method, however, does not measure UV radiation. A meter for UV may be worth purchasing if a large art investment is in need of protection.
- In general, 5-10 foot candles of light are the maximum recommended light level for the temporary exhibition of printed materials, certain photographs, certain paintings and textiles. Though, up to 15 foot candles may be a safe exposure for many oil paintings, gelatin silver prints and wood objects. Certain other objects claim to be virtually unaffected.
- Know your art: certain pieces will fade in only a few foot candles of light. In these instances, the above listed measures may not be sufficient. Identifying these pieces is most important and should be done with the assistance of art professionals.
FRAMING
Framing materials are not only a lovely compliment to a work of art. Framing can offer structural support and protection against minor environmental hazards. More importantly, inappropriate framing media can cause serious damage. Follow these general guidelines for maintaining a frame that is in good condition:
Framing materials are not only a lovely compliment to a work of art. Framing can offer structural support and protection against minor environmental hazards. More importantly, inappropriate framing media can cause serious damage. Follow these general guidelines for maintaining a frame that is in good condition:
- Framed paper items should only be mounted and matted with museum-standard acid-free materials, which are neutral or alkaline (have a pH of 7 or above). Unmatted items can become permanently stuck to the glass, particularly when exposed to high humidity levels. Direct contact with glass can also cause surface changes in the work.
- Items in contact with acidic materials can experience burns and general darkening. Spray mounts, rubber cement, laminating or tapes can cause irreversible staining, rippling and creases.
- When choosing a glazing, make sure that it offers UV-filtering protection to reduce the impact of light exposure. While plexiglass can be a more shatterproof alternative to glass for many framed works, powdery or loose material such as pastels or charcoal drawings should only be framed under glass. Acrylic materials can cause a static buildup that can lift these pigments away from the paper surface.
- A protective dust seal backing should be applied to avoid contamination by dirt, dust and insect pests.
- Proper hanging hardware should be attached to the frame rather than to the item's structural supports. Hang items from picture hooks, rather than nails, and always make sure there are enough to properly support the weight of the item.
- A professional art installer can assist in determining the best display and hanging system for your collection.
HANDLING
Overhandling is an easily preventable potential source of unintended creases, stains and tears - especially for materials weakened by age or damaged by improper storage or non-archival matting and framing materials.
Overhandling is an easily preventable potential source of unintended creases, stains and tears - especially for materials weakened by age or damaged by improper storage or non-archival matting and framing materials.
When handling is necessary, always use archival gloves to handle art or valuable paper materials. Simple contact with oils, perfumes, lotions or sweat present on human skin can cause discoloration.
Papers and documents that are regularly accessed can be photocopied or archivally framed so that they can be read without being handled unnecessarily. While photocopying does expose papers to a short intense burst of UV radiation and is not recommended for art pieces, this can be less harmful to documents than regular manipulation.
Never affix notes or paper clips to valuable documents. Tape or sticky notes can leave behind residues that are detrimental to paper; and, metal clips can cause creasing, corrosion and staining.
STORAGE
Items in your collection that are particularly delicate or taken out of general display should be securely stored in an inner closet or other similarly protected environment with stable climatic conditions. Care should be taken in choosing a proper storage location. Ideally, a closet or room should be designated for art storage and fitted with horizontal racks, flat files and a locked door.
Items in your collection that are particularly delicate or taken out of general display should be securely stored in an inner closet or other similarly protected environment with stable climatic conditions. Care should be taken in choosing a proper storage location. Ideally, a closet or room should be designated for art storage and fitted with horizontal racks, flat files and a locked door.
Art work should not be stored in attics, basements, garages or other areas that can experience extreme temperature changes or are susceptible to water damage.
Framed pieces should be stored vertically, separated by stiff boards to protect the image surfaces. Paintings that are improperly stacked can become dented or torn if the corners of one frame push into neighboring canvas surfaces.
As with items on display, art that is stored should be archivally secured using appropriate acid-free conservation materials. Textiles and unframed paper items should be stored in acid free storage boxes or placed in individual acid free folders. Separate each item with sheets of an archival storage medium. Protective window mats can also help to avoid direct contact whit the image surface. Place archival storage sheets inside each exposed window area of a mat.
Items with high acid content, such as photographs or natural textile fibers, should be wrapped in unbuffered materials. The boxes themselves should be stored horizontally to avoid stress on the outer edges of the material.
Lightweight collectible garments with strong shoulder seams may hang on padded wooden hangers (not wire or padded plastic hangers) and stored in muslin garment bags. Heavy, fragile or beaded material should be stored flat in an archival storage box with padding placed below seams or creases. Large flat textiles can also be wrapped with acid free material, rolled onto archival tubes and stored on a secure horizontal support. For more information on quilt storage, visit http://hollingercorp.com/Quilter.htm.
Avoid mothballs and cedar chests for textile storage. They can expose items to harmful off-gassing, and do not offer proven protection from insect infestations.
Also, avoid poster storage tubes, unprotected wood or cardboard, cellophane, wax paper, newspaper, and dry-cleaning bags. They can cause acid burn, off-gassing, residues and stains - especially in a closed environment.
Photographs should not be stored in self-stick photo albums. The adhesive can cause staining. Non-archival photo sleeves can expose materials to harmful vapors and may encourage moisture buildup.
Store items at least 4 inches above floor level and make sure that there is adequate air circulation.
If you have questions about appropriate storage systems, contact a professional conservator for advice and assistance.
CLEANING
Keeping your collection and storage areas clean is important for its preservation. If done improperly, however, cleaning can actually cause damage. Over-cleaning, for example, can cause foreign materials to become imbedded, and loose or powdery surfaces can be lifted off.
Keeping your collection and storage areas clean is important for its preservation. If done improperly, however, cleaning can actually cause damage. Over-cleaning, for example, can cause foreign materials to become imbedded, and loose or powdery surfaces can be lifted off.
Artwork, particularly paintings, should only be dusted every four to six months after a close inspection to make sure there is no loose or flaking material.
Use only delicate cleaning materials such as soft brushes for exposed areas slightly or a clean, damp cotton cloth that has not been used with cleaning solvents on glazed surfaces. Feather dusters should not be used as they can scratch and snag surfaces.
Over-cleaning can cause more damage. Foreign materials can become imbedded. Loose or powdery surfaces can be lifted off.
Never use liquid or commercial cleaners. They can react with the art media or expose the art to harmful fumes - this applies even for items under glass.
Vacuums with HEPA filters can remove most environmental particulates from the area around an art collection. Be sure to reach the top shelves and corner areas as well as the floor. This is often where insects reside in dust deposits.
Clean and replace heating and cooling unit filters regularly.
The safest way to ensure the safety of your collection is to leave all but routine dusting to a professional conservator.
PESTS
Humidity, warm temperatures, dust and food particles are all invitations for rodents and insects, which are naturally attracted to the cellulose fibers in many items and the adhesives used to mount them. When they are not consuming your valuables, they may be tunneling, nesting, laying eggs or secreting harmful substances - these can all cause permanent injury to valuables.
Humidity, warm temperatures, dust and food particles are all invitations for rodents and insects, which are naturally attracted to the cellulose fibers in many items and the adhesives used to mount them. When they are not consuming your valuables, they may be tunneling, nesting, laying eggs or secreting harmful substances - these can all cause permanent injury to valuables.
Infestations should be handled by a conservator in conjunction with a pest elimination professional. The art objects themselves will need to be cleaned in order to eliminate re-infecting the area with insects. Some insects, such as firebrats and silverfish, have larva and young that are nearly invisible to the eye. They can live for up to two years and go for extended periods of time with absolutely no sustenance.
Signs that you may have a pest problem include:
- Holes
- Grazed surfaces
- Droppings
- Hairs
- Skin flakes
- Bugs/Larva
- The presence of spiders (which consume insects)
- Keep potted plants away from art or art storage areas. They can attract insects. Trim hedges and flowering borders away from art and storage areas.
CARE OF NEW ART ACQUISITIONS
When introducing new items into your collection, it is important to have them cleaned, repaired and stabilized by a professional conservator. Even light dirt films and other small, seemingly unobtrusive marks, can quickly degrade materials. The presence of particulates can attract pests. Weak or torn areas can also threaten the structural integrity of the piece in the long term. A conservator can address these issues and make sure that new acquisitions are free of insects, mold, and other potential contaminants that could spread to other pieces in your collection.
When introducing new items into your collection, it is important to have them cleaned, repaired and stabilized by a professional conservator. Even light dirt films and other small, seemingly unobtrusive marks, can quickly degrade materials. The presence of particulates can attract pests. Weak or torn areas can also threaten the structural integrity of the piece in the long term. A conservator can address these issues and make sure that new acquisitions are free of insects, mold, and other potential contaminants that could spread to other pieces in your collection.
OTHER ENVIRONMENTAL HAZARDS
Art should be kept safe from environmental pollutants such as pesticides, cleaning fumes air fresheners, foggers, laminates, furniture sprays, cigarette smoke and heavy perfume.
Art should be kept safe from environmental pollutants such as pesticides, cleaning fumes air fresheners, foggers, laminates, furniture sprays, cigarette smoke and heavy perfume.
Additionally, art should be removed from any area where painting, plastering, wallpapering carpet installation or steam cleaning will occur. All of these can create harmful fumes, which can degrade the surface of art works. During any home improvement project, make sure that your collection is safe from debris. If the project is large scale or long term, you may want to move your art to a temporary storage facility for safe keeping. Return art only after the walls and floors are completely dry and chemical fumes have been cleared from the air.
For more advice, please visit our website's Tips for Your Collection section.
