Conservation and restoration of movable cultural property is a term used to denote the conservation of movable cultural property items in libraries, archives, museums and private collections. Conservation encompasses all the actions taken toward the long-term preservation of cultural heritage. Activities include examination, documentation, treatment, and preventive care, which is supported by research and education. Object conservation is specifically the actions taken to preserve and restore cultural objects. The objects span a wide range of materials from a variety of cultures, time periods, and functions. Object conservation can be applied to both art objects and artifacts. Conservation practice aims to prevent damage from occurring, a process known as 'preventive conservation'. The purpose of preventive conservation is to maintain, and where possible enhance, the condition of an object, as well as managing deterioration risks, such as handling and environmental conditions. Historically, object conservation was focused on the category of fine arts but now many different types of objects are conserved. Each type of object material, typically denoted by organic or inorganic then the specific medium, requires a specialized professional conservator and often requires collaborative work between museum staff, scientists, and conservators.
Object conservation involves the Conservation-restoration and preservation of a physical object. This type of conservator is differentiated from other specialists because they treat a broad range of objects and material types. This classification of material includes archaeological, ethnographic, historical, sculpture, decorative arts, and contemporary art.
History
Object conservation has been around ever since people have been amassing and assembling collections for others to enjoy. Conservation in its early history was conducted by skilled craftsman and tradesman who could repair and return the objects back into a useful working or exhibition condition. Over time, object conservation as a profession has developed to the point where specialization for objects and the materials out of which they are made have become the standard of modern conservation. Conservation skills are now being taught at institutions such as the master's degree program in art conservation at Winterthur and the University of Delaware, located in Newark, Delaware. This is an intensive three-year program, with facilities including conservation studios, laboratories, examination rooms and workshops available to students and faculty. These are housed in the Louise E. du Pont Crowninshield Research Building at Winterthur.
Causes of deterioration
Water causes damage and results from natural occurrences, technological hazards, or mechanical failures. Many cases of water damage can be traced to accidents or neglect. "A great many of the materials that museum objects are made of are highly susceptible to contact with water and can be severely damaged by even brief contact, while others may be exposed to water for longer periods without harm. This situation is complicated by the combination and range of materials that may comprise each object. In addition, the vulnerability of individual objects to water can be affected (i.e. increased) significantly by the state of the degradation of the materials." Water damage causes a variety of preservation concerns, including but not limited to: discoloration, cracking, softening, matting, distortion, mold growth, delamination, and swelling.
Fire is a risk to both objects and their collections, both humans and inanimate objects. Museums, libraries, archives and private collections are vulnerable to fire from a number of internal and external sources. Most museum fires begin as a result of human neglect and carelessness, or are intentionally set. Damage to objects can be irreparable or can be mitigated due to storage choices (like being in a glass case), the object's material(organic materials are more prone to damage), or safety precautions that the museum has invested in. Fires also create soot deposits which can cause discoloration, dull surface textures, and permanently alter objects.
Light fades materials. Colors that fade can disappear within as little as a few hours of direct sunshine, or just a few years at low museum lighting. But some types of objects are more fade resistant due to their specific materials. Ultraviolet light causes yellowing, chalking, weakening, and/or disintegration of materials. Infrared light heats the surface of objects, which is a form of incorrect temperature. Different deterioration phenomena often occur simultaneously.
Inappropriate temperature is another source of deterioration. There are several ways that temperature can cause object degradation. One being that the temperature is too high: this excess heat can cause chemical, physical, and biological phenomena. The most important phenomena for museums and archives is chemical: normal room temperatures are much too high for the long-term preservation of unstable human made materials, especially those carrying images, sound, and text. Another problem arise when temperature is too low. Overall, low temperature is beneficial to collections, but polymeric materials, such as paints, become more brittle and fragile. Some objects contain materials that will deform and weaken, or even melt, above a certain temperature.
Inappropriate relative humidity effects a wide range of object materials and storage solutions. Relative humidity is the quality of the air that ranges between damp and dry, which causes damage to objects. Damp is when the relative humidity is over 75%. Damp causes several types of deterioration: mold, rapid corrosion, and extreme forms of mechanical damage. Mold damages any form of organic material.
Physical forces are the results of both direct and indirect actions that impact both objects and their surroundings. "Physical force can damage objects directly by causing rotation, deformation, stress, and pressure. It may also damage objects indirectly by causing collision between objects or object parts. Damage from physical force ranges from imperceptible hairline fissures and minute losses, to large-scale effects such as crushing objects, collapsing floors, and, in extreme cases, destroying buildings. Five important force-related effects are: impact; shock; vibration; pressure; and abrasion."
Dissociation is an immaterial form of damage, rather than something physically done to an object. Damage can occur as: rare and catastrophic single events resulting in extensive loss of data, objects, or object values; sporadic and severe events occurring every few years or decades resulting in loss of data, objects, or object values; and continual events or processes resulting in loss of data, objects, or object values. Object conservation depends on objects remaining in well cared for environments with up to date records and locations. Dissociation can happen both as a direct consequence of actions, like removing a label tag or making errors in records, as well failing to perform actions, like not applying object numbers with permanent materials or not meeting legal requirements to prove ownership of an object.
Dust and chemical pollution is present in most environments, even in enclosed areas. "Pollutants are grouped into a range of compounds that can have chemical reactions with any component of an object. Pollutants can be gases, aerosols, liquids or solids of either anthropogenic or natural origin, and they are substances that are known to have adverse effects (negative consequences) on objects. Deposits of solid particles are considered pollutants, and while they may not necessarily cause damage, they are recognized as altering the aesthetic aspects of the objects. In some cases, fine particles deposited on an object's surface can be strongly bonded."
Burglars, thieves and vandals can completely remove an object from the control of an institution while either destroying it or damaging it in a wide variety of ways. Like dissociation, this cause of deterioration is much harder to control due to the institution's ability to address vulnerabilities in their facilities, security measures, or visitors. There are many systems of control that help to prevent theft and vandalism from ever occurring.
Pests are defined by the "National Park Service (NPS) Management Policies(2006) section 4.4.5.1 defines a pest as "an organism that interferes with the management objective of the site." For museums, a pest is defined as any organism that jeopardizes museum resources."Chapter 5: Biological Infestations Pests can include but are not limited to rodents, insects, and birds. An effective Museum integrated pest management program plays an integral and necessary part of every museum's collection care policy. Routine collections inspections can detect and reveal the presence of pests within the museum's buildings and storage areas. Common ways of reducing risks posed by pests are to reduce or eliminate food and water opportunities which provide an attractive lure for pests.
Item materials and types Item materials vary from organic, inorganic, and composite objects. Depending on the material being handled with for storage or needing conservation treatment, the conservator specializing in the specific type or range of objects is considered prior to treatment. According to the Code of Ethics Conservators are to only proceed treatment with care and complete understanding of the material.AIC, "Code of Ethics", American Institute for Conservation, 1994 Organic objects can involve "plastics, leather, feathers, bone, horn, ivory, hair, wood, and other plant and animal materials, including natural history specimens", and inorganic materials consists of "metals, glass, and ceramic materials and stone".n.d., "Objects Laboratory" , The University of Delaware, 2018 Composite objects are a mix of mediums that involve both inorganic and organic materials.
Organic Leather is a type of organic object that is prone to deterioration when exposed to "microorganisms, atmospheric gases, strong light, and extremes and fluctuations of humidity".Philip Ward, "The Nature of Conservation: A Race against Time", Getty Conservation Institution, 1986 Because of their vulnerability, these types of objects require persistent attention. Special treatment is needed for objects of leather if restoration of their original state is desired. For example, when leather is exposed to mold, the object should be treated with a vacuum and or alcohol if it has been tested that there is no discoloration or transferring of color.n.d., "Removing Mould from Leather – Canadian Conservation Institute", Government of Canada, 1993
Wood is another type of material that is identified as organic. Wood is a very absorbing material based on its environment. Thus, depending on the amount of water that is exposed in the air, the wood can expand and contract easily, changing the physical condition of the object.n.d., "Wood", American Institute of Conservation Wiki, 2016 This is the reason why wood material needs to be kept in a high controlled and consistent temperature and humidity levels. A too high relative humidity can cause wood to swell, and a too low relative humidity can cause the wood Bending or twisting, as well as the appearance of cracks and cracks. Extreme fluctuations of both can speed the deterioration process of the wooden object. With high relative humidity, wood is also prone to pests. An example of treatment would be to freeze the objects to kill any pests that may have been existing within.n.d., "Wood", American Institute of Conservation Wiki, 2016
Inorganic