The 10 Agents of Deterioration


By Rebecca Kennedy, Preservation Specialist

The 10 Agents of Deterioration are the most common and preventable problems that cause permanent harm to any collection, no matter if you are in a museum or at home. Being aware of these “agents” allows collectors to create a plan for the long term care and preservation for their artifacts. The 10 agents are: Fire, Water, Pest, Physical Force, Neglect, Theft and Vandalism, Incorrect Temperature, Incorrect Humidity, Chemical Deterioration, and Light.

Fire and water are both extremely damaging agents. Fire can lead to total loss of a collection, but water damage is more common, such as from household leaks, spilling beverages and floods.

Refer to caption
Metal from a Railway Mail Service car caught on fire.

Pest and physical force are both agents that can physically alter your artifact in some way that is irreversible. Pest can infest and make a meal out of any treasured letters and photos. Physical force is when something is broken or warped from dropping or knocking.

Refer to caption
Holes caused by pest feasting on paper.

Neglect happens sometimes without realizing it. When the history of an artifact is lost, such as names, dates or locations or the general internet of the collection it is considered neglect. Another form of neglect is forgetting to identify the agents of deterioration and preventing them.

Refer to caption
Box of improperly preserved family treasures.

Theft and vandalism are considered one agent as they are both crimes, whether it is premeditated or crime of opportunity. Unfortunately, both can mean the complete loss of an artifact.

Incorrect temperature and humidity are two different agents and both equally important. You have to have to have temperature and humidity, but it is important that it’s correct. Incorrect humidity can lead to mold growth or warping while incorrect temperature can lead to accelerated deterioration.

Refer to caption
Mold and warping caused by incorrect temperature and humidity.

Chemical deterioration is otherwise known as pollutants, which are gases, aerosols or dust. The spray from an aerosol cleaner or the accumulation of dust might seem insignificant, but if left for a long period of time, could accelerate decay of artifacts.
Light damage occurs when an artifact is exposed to light, indoor and outdoor, for extended periods of time. It is common to want to display valued family treasures in well-lit areas of your home, but it is doing irreversible fading.

Refer to caption
Faded stamp caused by light damage.

For more detailed information, visit The National Postal Museums Preserving and Conserving your Collection: Agents of Deterioration and Conservation Resources and References.


Rebecca Johnson

About the Author
Rebecca Johnson: "Trying to explain to people what I do day-to-day at the museum is almost impossible since everyday is different for me. Being a “jack-of-all-trades”, I oversee the museum's offsite storage facilities, re-house the collection, monitor the environment, assist the collections department, and many other tasks. Working on so many different projects keeps me on my feet most of the day, but it allows me to interact with every department, including USPS employees, which I really enjoy. I received a M.A. in Museum Studies from George Washington University and have been fortunate to work in several other institutions, including the British Museum."