Those fussy hygrometers

Q. I have several digital hygrometers from many different manufacturers. Why is there so much variation in the readings among each. If I place 2 or 3 in my humidor, the reading usually vary quite a bit. Any suggestions?
– Bob B., Andover, KS

A. I thought this question required a detailed answer from an expert, so I asked Michael Chunko of Csonka cigar accessories to take the lead. – G.K.

Let’s start with the realities of the two current hygrometer choices:

Analog hygrometers: These are mechanical, made with bi-metallic spring elements that have an accuracy variation of about 5%, +/- 2%. They typically have a manufacturing variation of 10%, depending on several factors. Once calibrated to eliminate the manufacturing variation (by twisting the spring) it should keep a fairly accurate reading forever.

Digital hygrometers: Fully electronic operation, using humidity sensors that vary widely by design. Generally speaking, they have an accuracy variation of about 3% +/- 1%. They also typically have a manufacturing variation of 5%, again, depending on several factors. Unfortunately, calibration after manufacturing is only just a great idea at this point in time. We believe there is no digital gauge that serves this need with high levels of dependability. However, Csonka is now working on a line of gauges that can be calibrated by the end user.

So, what can you do?

Choose an analog gauge which can be calibrated, and provides acceptable reading accuracy (because we are not scientists mandating 100% perfect humidity so “moisture ignition bombs” don’t go boom in the lab.)

Or, choose a digital gauge which cannot be calibrated, yet provides better than average reading accuracy (because we demand better accuracy and can do math), and know that a digital gauge is mis-calibrated by 6%, so just + or – the 6%.)

Personally (and professionally), though it is not the elegant solution, I’m OK with adding back or subtracting off what I already know. Furthermore, I’m a realist. Knowing that any cigars within the 65% to 75% range will keep them pretty much for 1000 years; that is if they don’t burn up before the end of the third millennium by unnatural causes (like a lighter) : – ))

– Michael Chunko
Csonka Worldwide Products