• 1 Vote(s) - 5 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Recalibration of Relative Humidity Probes

Hi Sam,

I ran calibration tests on my Tramex probes, although I felt like the Lone Ranger doing it!! I have been told my probes are the only ones that ever get sent back to the manufacturer..... Hmmmmm, that tells me people aren't checking their probes!

Tramex includes a vial of 75% salt solution. The procedure is to insert a probe into the salt solution vial and place the assembly in an area where it is not subject to fluctuations of temperature, light, and humidity. They suggest a closed drawer. Allow the probe to acclimate for a minimum of 2 hours. The probe should read within 3 percent of 75% RH. If it is not, repeat the test for another 2 hours.

Now let's stop and think about what the manufacturer just told us to do. Put their probe in a salt solution that we know is 75% RH. Let the probe sit 2 hours. (2 hours!!!!!) If the probe doesn't read 72% - 78% (wow, that's a range!) then let it sit for 2 more hours!!!

Now you are expected to take that probe to the field and install it in a hole and wait 45 minutes and trust the reading you get??? C'mon.... What if the probe reads 78%? Is the slab good? Could it be off by 3%? Maybe it is, but the other way!! Maybe the slab is actually 81%!! And we're not testing in a drawer here, we're in an area where air is flowing, sunlight is going across the floor ( readings will change if sunlight warms the probe barrel!)

So I always marked my probes with a sticker showing how far off they were on the last test. Now I had I guys favoring the low reading probes.....

After years of fighting with various probes, I went with Wagner and never looked back. I tested the Wagners every way I could and they always gave consistent dependable results. When I put 6 Tramex probes in a confined slab area (testing purposes) I would get 6 widely spaced readings. 6 Wagners gave me one reading.

I should say, I do not work for Wagner! I am an independent consultant that (in a previous capacity) took advantage of an almost unlimited budget for testing and determining the causes and remedies of flooring failures nationally.
JD Grafton
Concrete Answers for Flooring Problems
[email protected]

Messages In This Thread
RE: Recalibration of Relative Humidity Probes - fancrawl - 08-29-2009, 07:52 AM
RE: Recalibration of Relative Humidity Probes - CC Solutions - 12-17-2009, 12:16 PM

Possibly Related Threads...
Thread Author Replies Views Last Post
  Ambient humidity vs. RH Rubensgt40 19 40,280 10-16-2011, 06:09 PM
Last Post: CC Solutions
  Questioning the results of RH probes brian 4 10,174 10-13-2011, 03:09 PM
Last Post: CC Solutions
  Relative Humidity Probes Blake McFee 5 12,980 08-28-2011, 02:02 PM
Last Post: CC Solutions
  Relative Humidity Probe Depth mwoody 10 23,581 03-24-2011, 07:00 AM
Last Post: CC Solutions
  Specific humidity or ERH or Calcium Carbide? Andy 11 26,629 05-11-2010, 03:22 PM
Last Post: CC Solutions
  Relative Humidity Probes CMoore 1 8,091 02-20-2009, 01:08 PM
Last Post: rthompson

Digg   Delicious   Reddit   Facebook   Twitter   StumbleUpon  

Users browsing this thread:
2 Guest(s)