Enemies of History

• Age
• External Factors
  • Direct physical forces
  • Thieves, vandals, and “displacers”
  • Fire
  • Water
  • Pests
  • Contaminants
  • Radiation
  • Incorrect temperature
  • Incorrect relative humidity
• Technological Obsolescence

Age

Ageing is a natural and unstoppable process. Over time all records will deteriorate. Deterioration will occur at different rates depending on a variety of environmental factors and the relative stability of the raw materials used to create the records. However, given proper storage conditions and handling practices the ageing process can be slowed, at times, to a virtual standstill.

But sometimes age is not the primary factor governing the condition of a record. A combination of environmental conditions and what conservators call “inherent vice” (deterioration linked to the instability of a record’s component parts) determine the speed of deterioration.

External Factors

External factors also play a major role in an object's deterioration. The Canadian Conservation Institute (CCI) has categorized the conditions that contribute to the wear and tear of records into nine general categories:

1. Direct physical forces, such as the damage caused by accidental dropping and crushing
2. Thieves, vandals, and “displacers” (those who inadvertently lose or misfile)
3. Fire
4. Water
5. Pests, such as rodents, insects, and mould
6. Contaminants, such as air pollution, dust, and oil
7. Radiation (light, especially ultraviolet light (UV)) hastens the fading, darkening or other colour change of all organic materials and some coloured inorganic materials
8. Incorrect temperature (too high and materials discolour and disintegrate, and too low they become brittle)
9. Incorrect relative humidity (too high promotes mould growth and metal corrosion, and too low causes embrittlement)
   

Constant vigilance is key to preventing damage from these external factors. Prevention is the cornerstone of the Archives' preservation strategy. Archives conservators monitor the storage environments, develop policies and procedures, and advise and train staff on a variety of preservation related issues all in an attempt to prevent damage to the collections from occurring. It is far more cost effective to apply preventative measures than deal with the effect of damaged records. If damage does occur, conservators will intervene to stabilize the item and prevent further deterioration, possibly by treatment and/or creating custom-built storage containers.

Direct Physical Forces

The risk of damage through improper handling rises exponentially with highly fragile or brittle media such as glass plate negatives. The example on the left has been broken into two pieces.

Fire

All archival collections are flammable. Some types of records such as cellulose nitrate photographic negatives and motion picture film are more flammable than others. Fire can result in total or partial loss as in the example below so Archives conservators ensure storage areas are equipped with fire detection and suppression systems. Maintaining the Archives’ disaster response and recovery plan is also a responsibility of Preservation Services staff.

Soot as a by-product of fire can also cause serious damage to collections. In the example above left, all but the lower quadrant of this photograph suffered from soot damage. Soot can disfigure records and, if left untreated, it can be very difficult to remove.

Water

Just as fire can lead to the total loss of collections, so too can water. Many archival records incur serious damage if subjected to a flood situation. Mould can grow within 48 hours, so it is imperative to act quickly.

Click to see a larger image (87K)

The Archives' conservators continually monitor storage environments for sources of water leaks and provide disaster recovery advice and assistance to ministry staff throughout the provincial government.

Pests

Another way Archives conservators prevent damage to collections is blocking the entrance of pests into the storage environments.

The three major pest categories are rodents, mould and insects. In the example to the right, insects have eaten a lacy pattern into the edge of the paper and stained it with frass (fecal matter). Conservators inspect in-coming collections for infestation, and sometimes records are quarantined and fumigated prior to entering storage. Conservators also continually monitor storage areas for any signs of infestation.

Dust

Dust never sleeps. It is a silent and widespread contaminant that can evade even the best defences.

However, if left alone it becomes more than just an embarrassing symbol of bad housekeeping.

Dust can contain airborne pollutants that act as paper-destroying acids, mould spores and food particles that attract pests. Combating the spread of dust is just one of the many functions Preservation Services staff at the Archives perform.

Radiation

Light, particularly the ultraviolet (UV) component, is harmful both in terms of the intensity of the light and duration of exposure. Light damage is cumulative and cannot be reversed. Radiation can weaken and discolour materials.

In this watercolour the part of the image not protected from light has faded. A poor quality acidic mat has also resulted in staining of the image around the edges of the mat window. This is commonly known as mat burn.

If an item from a collection is to be displayed it is better to have a copy made and display the copy. If the original is used, protect it with ultraviolet (UV) filtered glazing. Also, it is important not to hang the item in direct light.

Incorrect Temperature

Heat is another source of deterioration that should be avoided. Many archival records consist of inherently unstable material. Paper made after 1850 often consists of ground wood pulp and is sized with acidic alum rosin (size is added to the paper to prevent writing and printing inks from feathering). Early plastic-based photographic negatives are composed of cellulose nitrate or cellulose acetate.

Unfortunately, these types of records will naturally deteriorate over time due to the inherent instability of their component parts. Heat accelerates the rate at which these chemical reactions occur, causing your collections to deteriorate even faster.

The higher the temperature, the faster and more extreme the deterioration.

With heat, cellulose acetate negatives discolour, channel, shrink and distort, as shown in the image to the right. Paper often turns brown and becomes very brittle.

Incorrect Relative Humidity

Incorrect relative humidity can lead to a variety of preservation problems. Higher levels of water vapour in the air can contribute to metal corrosion, mould growth and insect proliferation. Low relative humidity can cause some records to become brittle and more fragile to handle. Archives conservators monitor the storage environments for fluctuations in relative humidity and work with the Facility Manager to maintain a stable storage environment.

The image on the left above shows a record with visible signs of mould damage that is the result of a damp environment. But paper records don't need to be damp to the touch to exhibit deterioration. Higher humidity levels in the air can also lead to minor damage such as rust staining from corroding metal fasteners such as the stains from the paper clips in the detail on the right above.

Mould will develop if the relative humidity is above 75%, temperatures are warm, there is little airflow, and a food source is present.

All archival media is susceptible to damage from mould and it can completely destroy an archival record if left to grow unchecked, as in the two examples above.

Incorrect relative humidity can also cause damage to photographs and photographic negatives. In the example to the right, the emulsion has cracked and lifted due to expansion and contraction caused by fluctuations in temperature and relative humidity.

Technological Obsolescence

Technological obsolescence might also be added to the above list, particularly now that the digital age has arrived. Increasingly, the Archives receives electronic records in government record transfers or through private donations.

Electronic records present new preservation challenges. Similar to paper records, electronic records are still on a medium that requires safe storage and handling. However, unlike paper, which needs no special equipment to access its recorded information, electronic records require equipment for their information to be retrieved and decoded. Each new generation of equipment required to read electronic records is becoming obsolete at an unprecedented rate, as anyone who has an unreadable file on a 5-inch floppy knows.

Similarly, the electronic files may exist in obsolete applications and formats, like Word Star. In order to preserve electronic information so it can be accessed by future generations, the Archives must monitor technological advances and develop migration strategies to transfer electronic records to new technologies as they emerge.

Among the items pictured here are a number of digital formats, ranging from obsolete (e.g., the disk pack in the top left, the punch card in the bottom left) to "at risk" (the 9-track tape, front right) to the relatively current (Compact Disc and CD-R media, front centre). None of these formats is more than 30 years old, which is old by the standards of the technology, but not necessarily by the needs of the information contained on them. These were all "cutting edge" solutions in their day and, while the Compact Disc and CD-R media are currently in use, the others are now legacies, the contents of which must be copied to new media formats.

In contrast, the 16mm film and 1/4" reel to reel tape in the centre of the illustration are formats that have been in use for many years, but playback equipment is still readily available.