What is a Hygrometer?

Is the air dry in your house? A hygrometer can help. Learn how this tool works and what it can do for you.

Learn what a hygrometer is and how it can benefit you

“It’s not the heat, it’s the humidity!” That’s something we’ve all heard, or perhaps even said, at some time, unless maybe you’ve never been outside of the Sahara. Besides temperature, one of the most important factors in determining the comfort level of any environment is its humidity. Humidity is the level of water vapor in the air around you. Even though you think you are sitting in a dry room, the air you are breathing contains a percentage of water in the form of vapor gas. How high or low that moisture percentage is can make a significant difference in the way you feel.

One way that many of us can immediately judge the humidity level in the air is by how our hair looks and behaves. Hair reacts to increased humidity, causing frizz in curly hair, or weighing down straight hair into limp strands. In fact, it was this very noticeable quality in human hair that inspired Horace Benedict de Saussure to expand upon the idea of measuring water vapor in air. This idea of measuring amounts of humidity was first experimented with by Leonardo da Vinci. De Saussure took it further by inventing a mechanical device which used a human hair in the first simple hygrometer. He based his device on the observation that organic substances such as human hair expand and contract based on humidity.

A hygrometer is used to measure moisture content in the air, with the simplest ones still using human hair. Another type of hygrometer used today is known as a psychrometer or wet/dry hygrometer. It uses two thermometers, one with a wet bulb and one with a dry. Temperatures drop as the moisture evaporates from the wet bulb and the relative humidity is measured by the temperature difference between the two thermometers. Electric hygrometers are also now available for purchase in most hardware stores for use in homes and businesses.

When is a Hygrometer Used?

Hygrometers are used to measure humidity levels. They are used in places where it’s important to monitor moisture in the air; for instance in storage facilities, laboratories, greenhouses, museums, saunas, and many types of manufacturing facilities. Many people use them in households when humidity levels need to be monitored to prevent symptoms in sensitive people, to guard against mold and mildew, and to determine whether a humidifier or dehumidifier could be beneficial in order to keep indoor humidity levels comfortable. Some hygrometers come equipped with alarms to alert households to levels that drop below 30 percent or rise above 50 percent. Levels that don’t fall within that norm can be potentially harmful to your health.

Hygrometers in the Home

Meteorologists use hygrometers to measure humidity in the atmosphere and to predict weather pattern. The same technology can be used inside your home to alert you to potential problems when humidity levels rise or fall out of the normal range. Many people now use electric hygrometers in their homes in order to adjust humidity levels to address a variety of health concerns. Adding moisture through use of a humidifier can improve dry skin and hair, and address health issues such as dry sinuses, cracked lips and bloody noses. They also assist with respiratory problems. Many people who live in dry areas and desert climates use humidifiers to add moisture to the continually dry air to keep their homes more comfortable.In cases of higher than normal humidity in a home, a dehumidifier may be beneficial. Removing excess water vapor in the air limits growth of mold and mildew, and discourages allergens and dust mites. Mold allergies contribute to childhood asthma. A dehumidifier also helps an air conditioning unit to function more efficiently to save energy.

Large, commercial grade dehumidifiers may be used to treat flood or storm damaged homes and businesses to remove water vapor from air and belongings and to prevent subsequent growth of mold, mildew, fungi and bacteria.Whether in the home, work environment, or as a tool for forecasting weather, hygrometers have been helpful to humans for hundreds of years as an important tool to measure  humidity both inside our homes and in our outdoor environment.

Resources— Luma Comfort, ThoughtCo, Encyclopedia.com