Sculpture
Humidity
The change in ambient humidity has a major impact on the conservation of materials. The absorption or removal of humidity from the environment may cause changes in the shape of a work of art, and results are often irreversible, such as cracks, swelling, distortion etc. Also, the increased moisture in the environment can lead to corrosion or the development microorganisms. Furthermore, the increased humidity causes swelling of metal joints (which may be located internally in the structure of a work) due to the oxidation
of the surface of these joints and the significant increase of their volume resulting in mechanical stress, etc.
Temperature
The temperature of the environment constitutes a wear factor for artworks, especially in conjunction with relative humidity.
It is also a factor of deterioration for projects that have received conservation in the past, as this may alter the adhesives used or their protective surface.
In addition, any temperature changes cause expansion and contraction of a work's various
materials, leading to the development of mechanical stresses, causing cracks, delamination, etc.
Humidity Salts
Soluble salts are an important and very destructive factor in the deterioration of porous materials, regardless of their chemical composition. The main soluble salts that can affect artworks are chlorides, sulfates, nitrates and carbonates, which may come from the ground, various materials in proximity to the project, water irrigation, etc.
Water - frost
Water is a very important wear factor because it is an element that is encountered under several parameters such as transfer, crystallization etc. salts, transport of air pollutants (rain), chemical oxidation reactions etc., development of osmotic pressure, biological activity, mechanical stress etc.
Frost mainly affects works that are exposed to external environments in locations that experience very low winter temperatures. Water and humidity trapped or present inside the pores of a work freezes when the temperature drops below zero, expandings and causing cracking, erosion and other mechanical stresses.
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Lighting / UV radiation
Infrared (IR) and ultraviolet (UV) radiation can cause particular damage to some of the organic materials present in a scultures (e.g. fabrics or dyes) as well as in materials used during conservation. Wear and tear concerns aesthetics and the deterioration of the chemical composition or cohesion of a work of art.
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Biological attack
The biological infestation of sculptures mainly refers to fungi (mold), bacteria, algae, lichens, trees, plants, insects (wood-boring insects) and bird excrement, and less often to wear caused by small animals, such as mice, rats etc.
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>Human Factor
The damage which humans can impose on artwork may be involuntary (unknowingly causing wer through mistakes), vandalism, wear and tear, or even indirectly creating or accelerating deterioration factors in the environment housing sculptures.
Past maintenance
Materials used during past maintenance procedures which do not comply with current global standards of appropriate maintenance materials for works of art. Often, they have degraded aesthetically or lost their characteristic & nbsp;properties, for example their adhesiveness.
Unsuitable materials - Storage
Works of art are often packed with materials and in a manner that may be make them temporarily safe, but are unsuitable for long-term storage. For example, certain plastic materials are biodegradable and decompose over time, or adhesive tapes which lose their adhesive capacity after a while, or metal which is very well packaged and sealed airtight but becomes eroded by entrapped moisture.
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Endogenous factors
Construction Flaws& nbsp;
Some works have inherent defects in the way they were fabricated, which may be caused by the use of unsuitable or improperly treated material, but also due to mistakes made in the techniques used. This causes the materials to underperform, and lack maximum structural strength. If a sculpture has a defect in its construction, deterioration factors are usually difficult or impossible to treat, and only precautionary measures can be taken to protect it. An example of imperfection may be the wrong one ceramic firing process, so the problem occurs in the structure of the material and the sculpture shows features such fragility, brittleness, etc.
Incompatible materials
the different materials that can be used in parallel on a project often have different reactions to the deterioration factors and influence each other. The mismatch of materials can lead to their failure, reducing lifetime, or the selective corrosion of the materials for the protection of the other. For example, when creating plaster forms an iron frame is used to reinforce the plaster, which is hygroscopic material. However, if the frame is completely covered with plaster and not in contact with oxygen it does not corrode.
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External factors
Mechanical stresses
Sculptures experience mechanical stresses due to their construction (sometimes parts of the project support a lot of weights or have an inadequate support structure) or by erroneous handling when they are being moved, or by exogenous factors which cause structural damage (if something heavy falls onto the work, or it is located outdoors where children climb onto the sculpture). The mechanical stress can cause distortion or alteration of the sculptures shape or a break
Dust
Air pollution indoors may affect the conservation status of project. Dust and other micro-particles suspended in the atmosphere can cause wear abrasions to the surface or cause other wear factors due to their hygroscopic nature, such as the growth of microorganisms.
Air pollution
The material of works exposed outdoors, especially in an urban atmosphere where there is a large amount of varying airborne pollutants, may suffer degradation (sulfation or "sugaring") and the formation of black crusting.Seismic Hazards
Earthquakes pose a serious threat to sculptural work, and can cause fractures from falling materials from nearby building and from adjoining works (work can fall injuring each other).
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