Agents of Deterioration
Agents of Deterioration
Artists, conservators, curators and other cultural heritage professionals have been studying and trying to understand causes of damage for hundreds of years. In the 1990’s authors began publishing a more formal and comprehensive list of risks to art that we now refer to as the, ‘Agents of Deterioration’ (Michalski 1990). Collections care is not limited to works in museums. Steps can be taken for any type of object that you want to preserve. These are the most common causes of damage and ways to mitigate them.*
The 10 Agents of Deterioration
Physical forces
Physical forces are the outside forces that can cause damage to objects. These forces can be human error i.e., incorrect handling/packaging and impact (bumping into or dropping) to an object. They also include natural or environmental disasters (earthquakes, tornadoes, hurricanes). Types of damages caused by physical forces are dents, tears, scratches, breaks and fingerprints.
Damages from physical forces can be prevented with proper handling, packing and secure hanging hardware. Objects should be kept at a safe distance from active areas and limit handling.
Broken sculpture as a result of handling
Incorrect relative humidity (RH)
When the amount of moisture present in the air is too high, too low, or fluctuates greatly it can cause damage to an object. Many materials expand and contract with fluctuating RH leading to larger structural issues. High RH environments can lead to mold growth and pests, and it can cause corrosion on metal objects.
It is recommended to keep objects in environments with 35%-55% humidity. This number is an average and the needs of the object and materials being preserved should be taken into account. Once an ideal RH level is determined, fluctuations should be kept to a minimum and the humidity should be monitored regularly so action can be taken when needed.
Mold growth as a result of high humidity levels.
Incorrect temperature
The drastic or consistent changes in temperature can be damaging for many materials. High temperatures promote faster chemical reactions, soften materials and cause weakening of the object. Low temperatures can increase the brittleness in organic materials like wood or plastic.
Like RH, best practices for preserving objects is determining what materials are in your collection and what the ideal temperature is for them to be stored at. Around ~70° F is generally accepted as a safe temperature. Consistent monitoring of the temperature is recommended.
Pests
Pests include insects, rodents, microorganisms, fungi or any living thing that could damage an object. Some pests are attracted to certain materials, for example – moth larvae tend to seek out natural textiles and mice make nests out of paper and cardboard.
Integrated Pest Management (IPM) refers to the approach of individuals or institutions to monitor and prevent pest activity. It is recommended to place traps and routinely check your object and surrounding areas for evidence of pest activity. Regular dusting and cleaning of the surrounding areas is also recommended. Storage of materials that prevents pests from entering is also a good option in some cases.
Evidence of pest activity on canvas
Light
When light is consistently shining on an object it can cause changes in color, and increased deterioration of cellulosic materials (paper and canvas fibers). Damage from light is irreversible, therefore preventative measures are a high priority.
Keeping the object away from direct sunlight and minimizing exposure to light in general. Adding UV blocking shades to windows, blacking out windows completely when light is not needed, the use of light dimmers or changing light bulbs to a decreased wattage are all good options to prevent light damage.
Faded paint due to prolonged exposure to direct sunlight.
Pollutants
Pollutants are harmful chemicals (acidic gasses and aerosols), dust, and corrosives in the air. They can also come from cleaning supplies, and fragrances. These molecules can interact with your object and speed its deterioration or attract pests.
Best practice is to not spray anything around your objects. Dusting should be done with a soft brush or microfiber cloth and air fresheners should be placed away from an object. Some at-risk objects, such as silver tarnishing from sulfur-containing pollutants could be kept in a sealed case with scavengers that absorb pollution.
Dust accumulation on a mixed media artwork.
Water**
Water is nearly impossible to control, so the best method against it is prevention. It is best to place your object away from the threat of water or moisture (see #2). Objects that are around or submerged in water are susceptible to mold growth, structural damage, tide lines and the formation of salts.
Keeping your object off the ground and away from damp walls and open windows are ways of preventing water damage. It is also advisable to keep things like drinks and flower vases (filled with water) away from your objects.
Water damage of an acrylic on canvas painting
Fire**
If a fire occurs in the vicinity of an object, it can cause smoke damage and burns that could affect all or some of the object. Fire safety systems, such as fire detectors, fire extinguishers, sprinklers and hoses are crucial to have in any building or room for the safety of the people and objects.
While fire emergencies are unpredictable, there are precautions that can be taken to help prevent them and be prepared if a fire does start. Proper fire prevention protocols should be in place like unplugging unused devices and turning off stoves/ovens, not smoking indoors. The use of a fire-proof safe may also be an option for some works.
Soot accumulation on a wooden vanity.
Thieves and vandals
Intentional damage to an object is impossible to predict, but steps can be taken to prevent them by removing any ‘opportunity’. Enhanced security (cameras, alarms, safes, cases) can deter people from attempting to damage or steal your object(s).
In 1990 the Isabella Stewart Gardner Museum was victim to the theft of 13 works of art. The FBI Art Theft Program is still working with the museum to recover the lost works.
Photo: Creator: Josh Reynolds | Credit: AP
Copyright: AP2010
Neglect & Disassociation
Disorganization of insurance documents, conservation documents, or any paperwork regarding an object is a common way for any preventative measures to fall through the cracks.
Best practice is to keep all paperwork together in a safe place – keep physical and digital copies.
Photo by Laura Kells, the Library of Congress.
*If you have an object that has been subject to damages it is best to bring it to a professional conservator for assessment and treatment.
**An emergency preparedness plan is highly recommended for institutions and collectors to have in place and practiced regularly.
For more information on emergency preparedness visit the AIC website for resources or this AMA guide on disaster planning.
Further reading
For more information about the ‘Agents of Deterioration’ visit the American Institute of Conservation Wiki: https://www.conservation-wiki.com/wiki/Ten_Agents_of_Deterioration
Michalski, Stefan. 1990. “An overall framework for preventive conservation and remedial conservation." ICOM-CC, 9th Triennial Meeting.
Canadian Conservation Institute: https://www.canada.ca/en/conservation-institute/services/agents-deterioration.html
Postal Museum: https://postalmuseum.si.edu/collections/preservation/agents-of-deterioration.html
