Was on a job yesterday.... - Printable Version
+- Concrete Moisture Measurement Forums (http://www.wagnermeters.com/concreteforum)
+-- Forum: Concrete (/forumdisplay.php?fid=1)
+--- Forum: Flooring Success & Failure (War Stories) (/forumdisplay.php?fid=4)
+--- Thread: Was on a job yesterday.... (/showthread.php?tid=80)
Pages: 1 2
Was on a job yesterday.... - CC Solutions - 02-12-2011 12:30 PM
I was called in to prep a floor in a hospital that had experienced a failure. I was NOT doing testing, all I was asked to do was to bead blast the floor.
Of course I'm concerned (read - nosey ) and inquired about the moisture readings and the floor prep beyond my involvement.
Initial moisture readings (Wagner Rapid RH were specified) were above the limit for the floor adhesive and material. This means they would also exceed the patch manufacturer's requirements. I offered a mitigation system to keep the project flowing.
Two days later new moisture tests came in. They had fallen dramatically and were well within requirements. :o
Okay, fine, I guess my limited involvement means I should keep my nose out of this. After the old floor was removed and I came in to bead blast I pulled the probe sleeves out to see whose they were..... Well they obviously weren't Wagner. The readings were taken using a Protimeter. My heart just sunk. I have had so many problems with Protimeters I just get sick.
This is my opinion, and I don't work for Wagner, Howard Kanare is not my cousin, I have no monetary ties with Rapid RH in any way.... But if you are using the GE Protimeter and notice fluctuating readings and lower readings than the Rapid RH gives you, please think about why this is.
The Protimeter has perforated slots up the side of the sleeve. You can't measure the humidity at a 40% depth when the sleeve is open all the way from 10% depth to 40% depth. What you end up reading is the average of the entire range of concrete exposed. Add the fact that the probes must be allowed to acclimate in each hole for an hour, and in this instance there were three holes, meaning these probes would take a minimum of three hours to read (impossible when you are only allowed to run in between surgeries) and you can see why the Protimeter was the wrong probe to use... And remember the Protimeter must be checked for calibration per the ASTM.
Okay, in the end I am worried that the floor actually is too wet, there will be a failure and now my company is involved.....
RE: Was on a job yesterday.... - eaadams - 02-12-2011 03:02 PM
I wish I knew somewhere where I could sell our old protimeter.
However, I have found it sufficient for the other things it does such as concrete encounter type examination, ambient temps, and wood inspection. I just used it to find a leak in my house where the drywall shows high moisture right under a shower pan.
RE: Was on a job yesterday.... - CC Solutions - 02-12-2011 04:55 PM
I know exactly what you mean!!! I still have two Tramex meters but they never get a probe attached to them. One I carry along when I do lunch-n-learns just to show my audience what devices NOT to use. Then I whip out my Wagners and show them how to properly read slab RH...
RE: Was on a job yesterday.... - eaadams - 02-12-2011 09:02 PM
Yea in my lunch n learn I use the protimeter and hold it up to my skin. I say see people are mostly water. Then I hold it up against other things in the room to show them those things have less water. Then I tell them .... and this means NOTHING. all it means is there is more water in me than that. Has no quantitative value.
RE: Was on a job yesterday.... - Ernesto - 02-13-2011 08:44 AM
I still to this day cannot understand why people think perforated sleeves or even no sleeve can give you the correct rh number. The concept is not all that hard to grasp.
Take this example, get a dry sponge, dip the bottom part in water and take it out immediately, notice how the bottom is wet and SOME water will wick up the sponge. Now, lets say your going to drill a hole down in there at 40% level and have a perforated tube. Whats it going to read?
Thats how I explain it to people. Next time at lunch n learn take a dry kitchen scrubby sponge with ya.
RE: Was on a job yesterday.... - CC Solutions - 02-13-2011 09:37 AM
Excellent idea Ernesto!!! I believe I will steal that. It is a great visual for explaining CaCl tests also.
RE: Was on a job yesterday.... - Ernesto - 02-13-2011 04:47 PM
Thank you CC, just send money or left over meters. heh heh I try and post quality informative answers to threads. Only five more till I is a guru!
RE: Was on a job yesterday.... - eaadams - 02-13-2011 09:53 PM
(02-13-2011 08:44 AM)Ernesto Wrote: Take this example, get a dry sponge, dip the bottom part in water and take it out immediately, notice how the bottom is wet and SOME water will wick up the sponge. Now, lets say your going to drill a hole down in there at 40% level and have a perforated tube. Whats it going to read?
You can also use a sponge to show how concrete drys / curls. This was from Howard Kanare's not mine but he does it in his presentations. Shows how if you take a sponge and wet it, then let it dry on counter it will curl on edges much like a slab will curl along joints. Now take that same sponge and cover it in plastic. It won't curl the same way as it drys. I'm not eloquent enough to explain it but if THAT was on you-tube it would go to all 4,000 architects in my database.
RE: Was on a job yesterday.... - Ernesto - 02-14-2011 06:59 AM
You mean Howard is stealing my sponge idea now too?
RE: Was on a job yesterday.... - CC Solutions - 02-14-2011 12:53 PM
3 more Ernesto.... 3 more!!!!