How to Calibrate a Hygrometer? - Hygrometer Calibration

How to calibrate a hygrometer?

If you have an analog hygrometer, you want to make sure it is as accurate as possible for the best results and use. To achieve this, there is a simple calibration test you can follow on your own to achieve maximum accuracy called the salt test. The best part is, it only takes a few steps. But WAIT! Why are you bothering with this time-consuming test when you can purchase a digital hygrometer that never has to be calibrated, like the TP50!

Hygrometer Salt Test

You will need some supplies first:

• 2 teaspoons of salt
• Distilled water
• Zip lock bag
• Hygrometer that can be calibrated

Once you have all these supplies, you are ready to go. The whole process will take less than a minute to set up, but you must wait 12 hours for results!

1. Place your 2 teaspoons of salt into a small dish/bowl (some use a container cap of some sort)
2. Dampen the salt with the distilled water, do not put more than a few drops onto the salt, as you do not want it to dissolve.
3. Place your hygrometer and salt into the plastic bag, and make sure it is sealed shut
4. After 12 hours, if the hygrometer is correctly calibrated, the reading should be 75 percent humidity.
5. If your hygrometer is not reading the correct number, do not fret, simply use the manual dial to adjust your meter to 75 percent.
6. Mission successful!

Following these simple steps is an easy way to calibrate your analog hygrometer, but there is an even simpler solution, purchase a calibrated digital hygrometer, they already come calibrated! Digital hygrometers are a more reliable measurement tool than analog hygrometers because they have a 5%RH percent accuracy compared to the 10%RH percent accuracy of analog hygrometers.

ThermoPro digital thermometers have an accuracy of 2-3%RH as shown above. Digital hygrometers also require ZERO maintenance as they already come calibrated and do not require any special care. If you are looking for increased accuracy and reduced maintenance, head over to our TP50 product page and pick up yours today! Free shipping.