Thermal Hygrometer

Sometimes, in our work of Las Vegas water damage clean up, we need to measure the temperature and relative humidity of a particular location. This job is done by the help of a Thermal Hygrometers, whose purpose is to inform us how drenched that specific place is and if there has been any progress in drying.

Our business works with repairing water damage in residential houses, commercial and industrial locations around Las Vegas, North Las Vegas and Henderson. In our line of work, we often face situations where we need the help of a thermal hygrometer to assess the situation, to thermally measure the content of moisture in the environment. For this very important task, we rely on the RH 390 Thermal Hygrometer, supplied by Extech.

About the Product

The Extech RH 390 Thermal Hygrometer is a favorite of many because of it’s effective results and fast response time. It takes this equipment only seconds to measure the moisture content on a particular environment and to show the results, making it easy for us to take decisions.

This piece of equipment is easy to operate and use, and is designed to be handy and practical. With these, the change in thermal conductivity – which is, the humidity in air – is measured to indicate the amount of moisture in air, making it an important equipment in working with water damaged areas and materials.


  • Measures 0% to 100% RH of humidity
  • Measures -4° to 199° Fahrenheit of temperature
  • 0.1% RH of maximum resolution
  • ±2% RH of basic accuracy
  • ±1.8° Fahrenheit or ±1.0° Celsius of temperature accuracy
  • Dew point and wet bulb available
  • CE compliance available
  • Dimension: 7.75″ in height, 1.625″ in width and 1.25″ in depth


  • Less than 30 second response time needed
  • Displays humidity simultaneously with  temperature, dew point and wet bulb
  • One handed operation possible
  • Slim design with rubber grip for better handling
  • Dual light with back-lit display
  • Option to hold data
  • Low Battery indicator
  • Auto turn on and off
  • Minimum/maximum record available
  • Works with a 9-V battery
  • Available with a handy carrying case

Usage Story