Document Conservation and Preservation

Some Basic IssuesAnd Methods

Causes of Deterioration• Temperature and

Relative Humidity.• Atmospheric

Pollutants.• Light.• Biological Agents.• Abuse and

Mismanagement.• Disasters.

Paper and Acid• Acidity accounts for 90

percent of paper destruction.

• Paper production.• Reasons for acidity.• Definition of acid and

acid-free.

Relative Humidity• Amount of water vapor actually

held in a specific amount of air

• low relative humidity may lead to desiccation and embrittlement of some materials

• Fluctuations can cause cockling in paper, flaking ink, warped covers on books, cracked emulsion on photographs, and cause mold growth.

• Steady RH between 45% and 60% should be the goal

• no more that 5% shift in 24 hours period

Air Quality • Are external pollutants filtered out?

• Materials the displays are made from may outgas

• Other exhibition materials may outgas• Gases form acids that attack exhibition materials and effect each media differently

Silver Mirroring

Images courtesy of: http://iaq.dk/image.htm,

http://iaq.dk/silvermirror/Gallery/Allsurface2.html

Temperature• Temperature effects

relative humidity

• Heat accelerates deterioration: the rate of most chemical reactions, is approximately doubled with each increase in temperature of 10°C

• Should remain fairly stable at or around 18-21C

• no more than 5 degree shift per month

• Lighting may raise temperature

Photographic Security and Proper Storage

• Metal Containers.• Temperature Constant:

Prints, 65 degrees. Negatives, 45 degrees.

• Humidity Constant: 45 percent.

• Gloves and Use conditions.

• Separate Negatives from Prints.

Mold Damage

Cockling

Shrinking and Flaking Emulsion

Low Cost Solutions• Implement an

environmental monitoring program

• Avoid basements and attics

• Add weather stripping around doors and windows

• Install an air conditioning unit

• Ensure proper drainage around buildings

• Install storm windows to moderate temps and reduce condensation

• Use humidifiers and dehumifiers

Conservation Videos

http://www.youtube.com/watch?v=nmC10gCi-g0

http://www.youtube.com/watch?v=JXrs8L-LUd8&NR=1

National Archives

Flattening Maps and Plans

Photographic Preservation

http://www.youtube.com/watch?v=geqVsJJK5rs

http://www.youtube.com/watch?v=fcDlbNi-9D0&feature=related

The Archives Reading Room