Barigo German "Haar" Precision Synthetic Hair Hygrometer
A hygrometer made by Barigo, one of Germany's leading precision instrument manufacturers, founded in 1926.
This hygrometer uses a synthetic hair to move the needle, and doesn't need to be humidified ever few weeks like a natural hair hygrometer does.
If the hygrometer is not being used, we still recommend humidifying the hygrometer to 70% twice a year, or keeping it in a sealed, air-tight container when not in use, to keep its elasticity and accuracy.
Barigo hygrometers do not come pre-calibrated, and should be recalibrated every 3 months to ensure accurate reading and a long life.
To calibrate, fill a sizeable saucepan a quarter full of tap water and place the hygrometer on a stand in the water, so that the bottom of the hygrometer is suspended over (but not touching) the water. It is important that the instrument does not drop into the water (it might be prudent to secure the hygrometer on to the stand with a rubber band or similar support). Finally, place a well-fitting lid over the saucepan, and leave to stand for approximately 6 hours. Immediately on opening and removing the hygrometer, proceed as follows: Whatever the reading is (this could be off-scale) use a small screwdriver and gently turn the small recessed screw at the back of the instrument to read 95%. Return the hygrometer to its original location. After a few hours, the hygrometer will automatically adjust itself to the appropriate reading of the relative humidity which prevails. Direct reading Hygrometers have an accuracy of between 3% to 5% RH. Unlike absolute humidity, relative humidity is a very generous value so that a few percentage points either way are acceptable for the majority of applications. Accuracy depends on calibration; regular maintenance (re-calibration and re-humidification) is therefore vital.
Product dimensions: 3½ in x 3½ in x ¾ in Made in: Germany Made of: Chrome and stainless steel with synthetic hair Made by: Barigo Pre-calibrated: No System: Synthetic hair tension Resolution: 1 RH up to 70 RH, and 2 RH after 70 RH Measuring range: 10 RH to 100 RH