• 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

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 41,504 10-16-2011, 06:09 PM
Last Post: CC Solutions
  Questioning the results of RH probes brian 4 10,487 10-13-2011, 03:09 PM
Last Post: CC Solutions
  Relative Humidity Probes Blake McFee 5 13,342 08-28-2011, 02:02 PM
Last Post: CC Solutions
  Relative Humidity Probe Depth mwoody 10 24,252 03-24-2011, 07:00 AM
Last Post: CC Solutions
  Specific humidity or ERH or Calcium Carbide? Andy 11 27,481 05-11-2010, 03:22 PM
Last Post: CC Solutions
  Relative Humidity Probes CMoore 1 8,281 02-20-2009, 01:08 PM
Last Post: rthompson

Digg   Delicious   Reddit   Facebook   Twitter   StumbleUpon  

Users browsing this thread:
1 Guest(s)