Controlling the museum environment is very important for taking care of collections. Museum collections may contain different types of objects that are made from a variety of materials. In order to take care of these objects, museums have to manage and control the museum environment, which includes pests, pollutants, temperature and relative humidity (the amount of moisture in a given volume of air at a specific temperature).

For this experiment, we will be examining the effects of a damp and salty micro-environment on different materials. This will provide insight into how various objects that museums care for may be affected.

Please note: whatever you put in the micro-environment may change or deteriorate, so please do not use anything valuable or important to you!

Materials

• •  Water
• •  Table salt
• •  Sealable container (glass preferable, and as airtight as possible)
• •  Cotton balls or pads
• •  Kitchen scale (optional)

Options for test objects:

• •  Card stock or paper, marked with:
  • ◦  Colour felt marker
  • ◦  Pencil
  • ◦  Ink pen
• •  Wood piece
• •  Copper (e.g. a penny, the older the better—check online resources for copper content)
• •  Iron or iron alloy (e.g. a nail)
• •  Potato chip
• •  Leather
• •  Photograph
• •  Wood dowel
• •  Stone
• •  Glass
• •  Textile
• •  Yarn
• •  Glass

Examples of test objects: 

Instructions

1. Gather your test objects.
   • ◦  You do not need everything listed above—the first five listed above are ideal.
   • ◦  Make sure everything is small enough to fit in the container.
   • ◦  Mark your card stock or paper with felt, pencil and ink.
2. Document each object.
   • ◦  Note its appearance, size, weight and colour.
3. Write a scientific hypothesis (educated guess) about what you expect to observe in your micro-environment.
   • ◦  Note the container’s location, the room temperature, light sources, and anything else you think might affect your micro-environment.
4. Mix 1.5 teaspoons of table salt into 50 mL of warm water, then use solution to saturate the cotton balls.
5. Place the cotton balls at the bottom of your container.
6. Place your test objects into the container.

   

   • ◦  Keep in mind that you want to be able to see everything throughout the experiment without breaking the seal.
7. Document how your micro-environment looks on day 1.
8. Check your micro-environment daily and record your observations for three weeks.
9. After the three weeks, remove your objects from the micro-environment and note any observations.
10. Allow at least 24–48 hours to pass before checking the materials again and note any further changes.
11. Draw conclusions:
    • ◦  What happened?
    • ◦  Why did it happen?
    • ◦  What did you expect to happen, but it didn’t?

Once you’re done with your experiment, click here to see the results on our example test objects, and compare them to your own observations.