Any of several instruments used for measuring atmospheric humidity. Some types of hygrometers are:
- Psychrometer - measures the temperature difference between a wet-bulb and a dry-bulb thermometer. A sling psychrometer is mounted in a frame, then whirled in the air for ventilation.
- Hair hygrometer - measures the expansion and contraction of a human hair that is mounted under tension. A gold beater's skin hygrometer uses a proteinaceous membrane for the same type of measurement.
- Dew-point hygrometer - measures the temperature for the formation and evaporation of dew that is observed using a photoelectric cell.
- Diffusion hygrometer - measures the diffusion of water vapor through a porous membrane.
- Lithium chloride hygrometer - measures the temperature and electrical conductivity of a hygroscopic salt that becomes conductive when it absorbs water.
- Liquid crystal hygrometer - contains several chemical salts that respond to different humidity levels by rearranging their crystal structure. It never requires calibration.
Synonyms and Related Terms
dial hygrometer; hair hygrometer; dew-point hygrometer; diffusion hygrometer; lithium chloride hygrometer; liquid crystal hygrometer; hygrometr (Ces.); Hygrometer (Dan., Deut., Ned., Sven.); hygromètre (Fr.); higrómetro (Port.)
Resources and Citations
- Boise Cascade Paper Group, The Paper Handbook, Boise Cascade, Portland OR, 1989
- Marjorie Shelley, The Care and Handling of Art Objects, The Metropolitan Museum, New York, 1987
- Matt Roberts, Don Etherington, Bookbinding and the Conservation of Books: a Dictionary of Descriptive Terminology, U.S. Government Printing Office, Washington DC, 1982
- Dictionary of Building Preservation, Ward Bucher, ed., John Wiley & Sons, Inc., New York City, 1996
- Van Nostrand's Scientific Encyclopedia, Douglas M. Considine (ed.), Van Nostrand Reinhold, New York, 1976
- Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
- The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998
- Wikipedia: http://en.wikipedia.org/wiki/Hygrometer (Accessed Jan. 15, 2006)