Museums
Museum collections store and display delicate items, many of which are centuries old; if these artifacts are improperly cared for, they may deteriorate rapidly. Consequently, museums need to maintain an environment that will help prevent decay in paintings and other fragile items. Humidity is a key consideration because excess humidity can promote mold growth. If the humidity fluctuates frequently, wooden items can shrink or warp, paint can chip from canvases, or undesirable chemical reactions can take place. Museums often monitor humidity with the aid of a hygrometer.

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Greenhouses
Greenhouses help create controlled conditions for plant growth, since they make it possible to regulate light, humidity and temperature. Measuring humidity inside the greenhouse with a hygrometer--and altering the humidity as needed--can help ensure optimum plant growth.

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