Principles of Archival Preservation: Agents of Deterioration and Preservation Strategies

Archivists preserve archival materials, ensuring that historical records remain accessible for future generations. Archival preservation involves understanding how various factors contribute to the deterioration of materials and implementing strategies to protect them from damage. The fundamental principles of archival preservation focus on the agents of deterioration, preventive conservation, and essential preservation strategies applied in archival settings.

5 Agents of Deterioration

Archivists must consider several environmental and physical factors contributing to the gradual deterioration of archival materials. These factors, often called the “agents of deterioration,” can impact many items, from paper and photographs to textiles and audiovisual media. Understanding these agents is the first step in developing a comprehensive preservation strategy.

Light Exposure

Exposure to light, particularly ultraviolet (UV) light, can cause irreversible damage to archival materials. Light exposure accelerates the chemical breakdown of paper, textiles, and photographs, leading to fading, discoloration, and brittleness.

The damage caused by light is cumulative and cannot be reversed, making it essential to control light levels in storage and display areas.

Temperature Changes

Fluctuations in temperature and humidity can cause physical and chemical changes in archival materials. High temperatures speed up chemical reactions that degrade paper and other organic materials, while low humidity levels can cause paper and textiles to become brittle.

Conversely, high humidity promotes the growth of mold and encourages pest activity. Maintaining stable environmental conditions is crucial to minimizing the risk of damage.

Pests

Insects, rodents, and other pests can cause significant harm to archival collections. Pests are attracted to the organic materials found in paper, books, and textiles, and their feeding and nesting activities can lead to holes, tears, and staining. Regular inspections and integrated pest management (IPM) techniques are necessary to detect and control infestations.

Pollutants

Pollutants, such as dust, dirt, and airborne chemicals, can accumulate on the surface of archival materials, leading to soiling and abrasion. Certain airborne pollutants, like sulfur dioxide and ozone, can also cause chemical reactions that result in material fading and weakening. Proper storage and air filtration systems can help reduce the impact of pollutants on collections.

Physical Forces

Physical forces, such as handling, pressure, and vibration, can cause tears, creases, and breaks in archival materials. Improper handling and inadequate storage solutions are familiar sources of physical damage. Ensuring that materials are properly supported and handled with care is a basic but vital aspect of archival preservation.

Under Control: Preventive Conservation

Preventive conservation focuses on minimizing the risk of damage to archival materials by controlling the environment and implementing storage and handling practices.

Unlike conservation treatments, which are applied to items that have already sustained damage, preventive conservation aims to prevent deterioration before it occurs. This approach extends collections’ lifespan and reduces the need for costly and invasive treatments.

5 Basic Archival Preservation Strategies

Archivists can implement various preservation strategies to protect their collections from the agents of deterioration. While large institutions may have dedicated conservation staff and sophisticated environmental controls, smaller organizations can still take meaningful steps to ensure the longevity of their materials.

Temperature and Humidity Control

Monitoring temperature and humidity levels is a critical component of archival preservation. Ideal conditions for most paper-based materials are temperatures between 65-70°F (18-21°C) and relative humidity levels between 30-50%. Digital dataloggers and hygrometers can track environmental conditions and detect fluctuations. Dehumidifiers, humidifiers, and HVAC systems can help maintain stable conditions when necessary.

Choosing the Right Storage Solutions

Selecting appropriate storage solutions is key to protecting materials from light, pollutants, and physical forces. Acid-free folders, boxes, and tissue paper provide a stable environment for paper-based items, while polyester or Mylar enclosures can store fragile photographs and documents. Vertical storage is preferred for books and bound volumes to prevent spine damage, while flat storage is recommended for oversized items like maps and posters.

Integrated Pest Management

An effective Integrated Pest Management (IPM) program involves regularly inspecting storage and display areas and implementing measures to keep pests out. Tasks may include sealing gaps, maintaining cleanliness, and using traps to monitor pests. Avoiding food and drink in collection areas is a simple, effective way to prevent infestations.

Limiting Light Exposure

Limiting light exposure is crucial to preserving the color and integrity of materials. UV-filtered lights and window coverings can help reduce the impact of light, and storing sensitive items in dark storage areas when not in use will further protect them. For materials on display, consider rotating items to limit their light exposure over time.

Proper Handling

Proper handling and support are fundamental to preventing physical damage. Always use clean, dry hands or wear gloves when handling delicate items. Support materials with both hands or use trays and supports to move large or fragile items. Avoid opening books or documents too far or forcing them to lie flat when working with them, as this can strain bindings and spines.

Mitigating Archival Risks Begins with Understanding

Archival preservation is a multifaceted discipline that requires understanding the factors contributing to material deterioration and implementing strategies to mitigate these risks. By controlling environmental conditions, using proper storage solutions, and carefully handling items, archivists can protect their collections from harm and ensure longevity.

Whether working in a large institution or a small community archives, adopting basic preservation principles is essential to maintaining the accessibility and integrity of shared cultural heritage.