To preserve the objects collected and thereby prevent them from deteriorating, they must be placed in the appropriate conditions. Several factors can accelerate the deterioration of the items: humidity, pests, dust, light and temperature are all among the enemies of preservation.


Humidity

The collector must not eliminate humidity, but rather control it; each object has its own ideal humidity level. Many objects react strongly to variations in humidity in the air. When the level is too low, organic materials such as skin or leather may crack. When the humidity is too high, mould may be seen to appear on organic materials, and oxidation (rust) can be seen on metals. Also, in an environment where there is considerable variation in the rate of humidity, some objects may be subject to repeated swelling and shrinking, which can lead to their breaking.


To measure the relative rate of humidity a hygrometer is used. As a general rule, the relative humidity should be kept between 40 and 60 % to avoid damaging objects and prevent the appearance of mildew. At home, we suggest that collections not be stored in an unheated space b Read More
To preserve the objects collected and thereby prevent them from deteriorating, they must be placed in the appropriate conditions. Several factors can accelerate the deterioration of the items: humidity, pests, dust, light and temperature are all among the enemies of preservation.


Humidity

The collector must not eliminate humidity, but rather control it; each object has its own ideal humidity level. Many objects react strongly to variations in humidity in the air. When the level is too low, organic materials such as skin or leather may crack. When the humidity is too high, mould may be seen to appear on organic materials, and oxidation (rust) can be seen on metals. Also, in an environment where there is considerable variation in the rate of humidity, some objects may be subject to repeated swelling and shrinking, which can lead to their breaking.


To measure the relative rate of humidity a hygrometer is used. As a general rule, the relative humidity should be kept between 40 and 60 % to avoid damaging objects and prevent the appearance of mildew. At home, we suggest that collections not be stored in an unheated space because there are often great variations in humidity and temperature.

© 2010, Musée de la nature et des sciences inc. All Rights Reserved.

The skin on the muzzle of this Wapiti or American Elk is cracked. Cervus elaphus

The skin on the muzzle of this Wapiti or American Elk is cracked. Cervus elaphus

Musée de la nature et des sciences de Sherbrooke

© 2010, Musée de la nature et des sciences inc. All Rights Reserved.


According to the Canadian Conservation Institute, pests include those living organisms able to modify, damage or destroy the objects in a collection. Most pests can be classified in three categories: microorganisms, insects and rodents.


Microorganisms

Microorganisms include species of fungi and bacteria that can develop on objects in the collection and cause damage to them. They often create, by their very presence, an environment that promotes an increase in humidity, and as well, they attract other organisms, such as insects, that also attack the materials we are trying to protect.


Insects

The specialization of each species of insects, their small size, their facility in moving from place to place and their abillity to reproduce as well as their acute senses constitute a serious threat for preservation. In their hunt for food and shelter, insects can actually totally destroy organic material (leather, wood, etc.) in a collection.


Rodents

Rats and mice are excellent climbers, burrowers, swimmers and chewers. Because of their high reproduction rate, they disperse in search of food and materia Read More
According to the Canadian Conservation Institute, pests include those living organisms able to modify, damage or destroy the objects in a collection. Most pests can be classified in three categories: microorganisms, insects and rodents.


Microorganisms

Microorganisms include species of fungi and bacteria that can develop on objects in the collection and cause damage to them. They often create, by their very presence, an environment that promotes an increase in humidity, and as well, they attract other organisms, such as insects, that also attack the materials we are trying to protect.


Insects

The specialization of each species of insects, their small size, their facility in moving from place to place and their abillity to reproduce as well as their acute senses constitute a serious threat for preservation. In their hunt for food and shelter, insects can actually totally destroy organic material (leather, wood, etc.) in a collection.


Rodents

Rats and mice are excellent climbers, burrowers, swimmers and chewers. Because of their high reproduction rate, they disperse in search of food and materials in the areas where collections are housed. They cause damage to the specimens or objects by removing materials to make their nests, leaving greasy traces in their wake, and by making themselves at home near and sometimes in the collections.



© 2010, Musée de la nature et des sciences inc. All Rights Reserved.

Insect damaged by mildew Bolitotherus cornutus Forked Fungus Beetle

Insect damaged by mildew Bolitotherus cornutus Forked Fungus Beetle

Musée de la nature et des sciences de Sherbrooke

© 2010, Musée de la nature et des sciences inc. All Rights Reserved.


A book damaged by termites

A book damaged by termites

Musée de la nature et des sciences de Sherbrooke

© 2010, Musée de la nature et des sciences inc. All Rights Reserved.


Dirt is particularly harmful because it discolours or soils surfaces, which changes the appearance of objects. Particles left on the object may also change its composition and hasten deterioration. Cleaning the accumulated dirt is a delicate operation when fragile or porous surfaces are involved. This is why strategies to reduce the concentration of particle in the air are necessary. For example, the object may be placed in a drawer, a box or an envelope to protect it from dirt. It can also be safely presented in a glassed display case.
Dirt is particularly harmful because it discolours or soils surfaces, which changes the appearance of objects. Particles left on the object may also change its composition and hasten deterioration. Cleaning the accumulated dirt is a delicate operation when fragile or porous surfaces are involved. This is why strategies to reduce the concentration of particle in the air are necessary. For example, the object may be placed in a drawer, a box or an envelope to protect it from dirt. It can also be safely presented in a glassed display case.

© 2010, Musée de la nature et des sciences inc. All Rights Reserved.

Light is essential for people to be able to appreciate the objects in the collection. Unfortunately, light damages these objects by causing irreversible changes, such as discolouration, yellowing and fragilization or embrittlement. To ensure the ideal conditions for preservation, curators must find the right balance between protecting objects against the destructive impact of light and lighting which provides inadequate visibility for the visitors to see the objects. Too bright a light and the presence of ultraviolet rays are actually a major cause of degradation. Whether in the museum or in your home, objects in a collection should be protected by keeping them out of the light or adjusting the intensity of the lighting. Of course, it is also necessary to keep objects from being exposed to the harsh rays of the sun.
Light is essential for people to be able to appreciate the objects in the collection. Unfortunately, light damages these objects by causing irreversible changes, such as discolouration, yellowing and fragilization or embrittlement. To ensure the ideal conditions for preservation, curators must find the right balance between protecting objects against the destructive impact of light and lighting which provides inadequate visibility for the visitors to see the objects. Too bright a light and the presence of ultraviolet rays are actually a major cause of degradation. Whether in the museum or in your home, objects in a collection should be protected by keeping them out of the light or adjusting the intensity of the lighting. Of course, it is also necessary to keep objects from being exposed to the harsh rays of the sun.

© 2010, Musée de la nature et des sciences inc. All Rights Reserved.

Luna Moth (Actias luna) preserved away from light

Luna Moth (Actias luna) preserved away from light

Musée de la nature et des sciences de Sherbrooke

© 2010, Musée de la nature et des sciences inc. All Rights Reserved.


Luna Moth (Actias luna) discoloured by light

Luna Moth (Actias luna) discoloured by light

Musée de la nature et des sciences de Sherbrooke

© 2010, Musée de la nature et des sciences inc. All Rights Reserved.


Storing at temperatures that are too cold or too hot presents a risk of deformation, weakening or breakage of many objects. Rapid variations in temperature can also cause similar damages. On the other hand, it is not always the temperature itself that affects the specimens, but also the conditions associated with inappropriate temperatures. For example, even if the humidity is high, mildew will grow only if the temperature goes above 4 degrees Celsius.
Storing at temperatures that are too cold or too hot presents a risk of deformation, weakening or breakage of many objects. Rapid variations in temperature can also cause similar damages. On the other hand, it is not always the temperature itself that affects the specimens, but also the conditions associated with inappropriate temperatures. For example, even if the humidity is high, mildew will grow only if the temperature goes above 4 degrees Celsius.

© 2010, Musée de la nature et des sciences inc. All Rights Reserved.

Learning Objectives

• To discover the main factors that can interfere with preserving the objects in the collection;

• To find solutions or explanations for scientific and technological problems;

• To discover how matter is transformed depending on the conditions in the environment.


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