Document Conservation and
Preservation
Some Basic Issues
And 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
National Archives
http://www.youtube.com/watch?v=nmC10gCi-g0
Flattening Maps and Plans
http://www.youtube.com/watch?v=JXrs8LLUd8&NR=1
Photographic Preservation
http://www.youtube.com/watch?v=fcDlbNi9D0&feature=related
http://www.youtube.com/watch?v=geqVsJJK5rs
The Archives Reading Room