Hygrometer Facts

Hygrometer Facts
A hygrometer is a tool used to measure the humidity, or moisture, in the atmosphere. Leonardo da Vinci invented the first version of the hygrometer in 1480, and in 1755 a more modern version was invented by a polymath Johann Heinrich Lambert. Measuring humidity has been a challenge for meteorology due to difficulty in operating and maintaining instruments so that they remain reliable. There are a variety of hygrometer designs and some work better under certain circumstances than others. Hygrometers work by using a material such as a hair to attract moisture and then a calculation is made based on the change to the material to determine humidity.
Interesting Hygrometer Facts:
In 1783 Horace Benedict de Saussure invented a hygrometer using a human hair to determine relative humidity.
A hygrometer is also known as a psychrometer.
A hygrometer can also be referred to as a 'humidity sensor' or a 'relative humidity indicator'.
Hygrometers measure RH (relative humidity). It can take as long as two hours to get an accurate reading from a hygrometer. Results are not instant like with thermometers.
Humidity is the moisture, or water vapor in the atmosphere. It is caused by evaporation and condensation.
When humidity is measured as the amount of water vapor in a specific unit volume of air it is referred to as absolute humidity. When it is measured as moisture in the atmosphere to moisture the atmosphere can hold it is referred to as relative humidity.
Hygrometers should not be placed near a heat source as this will change the reading. They should be placed where there are sins of humidity.
The two main hygrometer types are the mechanical hygrometer and the wet and dry bulb psychrometer.
When humidity is too high it can be dangerous for people. When it is too high it can cause heat stroke. Humidity is the cause of the sticky feeling on really hot days.
The wet and dry bulb psychrometer works by evaporating water on a wet bulb which causes the bulb's temperature to drop. It shows a lower temperature than the dry bulb. The difference is calculated and used to determine relative humidity.
Bad hair days (frizzy uncontrollable hair days) are caused by humidity in the air. Hair responds very well to changes in humidity and this is why it was used to create one of the first hygrometers in history.
Modern hygrometers include capacitive, resistive, thermal and gravimetric hygrometers.
Humidity can damage furniture and other objects such as musical instruments as it can cause wood and other material to swell, as well as leave moisture and condensation stains.
Weather reporters report on relative humidity as this can help warn people about potential health risks in high humidity conditions.
Hygrometers are used in greenhouses to help regulate the moisture content in the atmosphere which can affect plant growth.
Hygrometers can be useful in saunas, humidors, museums, and incubators to help measure the humidity.
Instruments such as guitars, pianos, violins, and harps can be seriously damaged by humidity and many musicians use hygrometers to help determine proper humidity.

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