24 or 72 Hours: Which Number for Rapid RH® Testing?
Wouldn’t it be great if you didn’t have to wait the full 72 hours, as specified in the ASTM F2170 Standard, to know confidently what your relative humidity (RH) measurement was going to be?
NOW, you don’t have to wait until 72 hours have elapsed. You can take your Rapid RH® measurement at 24 hours—a full 48 hours ahead of the 72-hour mark—and be certain that this is the same number you will see at 72 hours.
That is one of the key findings of a Precision and Bias (P&B) study that was conducted by an independent laboratory under the direction of an ASTM task group.
ASTM’s P&B Study
In the study, the laboratory tested six manufacturers’ RH products, taking temperature and RH readings at periods of 1, 2, and 4 hours, as well as 24, 48, and 72 hours.
The results? The 24-hour readings for the Rapid RH® are essentially identical with the 72-hour readings. There was some slight variation, but it fell well within the acceptable range as laid out by the Standard.
In other words, the test showed that when you conduct Rapid RH® testing properly in the field, you can confidently and soundly predict what the Rapid RH® measurement at 72 hours will be, based on the 24-hour measurement.
Of course, you still need to take measurements at 72 hours to fulfill the Standard’s requirements. But there is no longer a doubt about how long you must wait to get the data you need to move forward on your project. With the P&B study’s results, it’s official: with Rapid RH® testing conducted in accordance with ASTM standards, there is no functional difference between the reading you get at 72 hours and the one you get at 24 hours.
Accuracy and Speed…In the Real World
These results are great news for those utilizing Rapid RH® measurement testing to ensure their flooring projects are not compromised by moisture-related problems.
Basically, it means that flooring contractors have a scientifically valid way to help accelerate their project workflow. If the readings for their finished flooring products are acceptable, they can take steps a full 48 hours before testing is “complete” to ensure that everything is in place and ready to move forward in terms of flooring installation. On the other hand, if the readings are not acceptable, they possess this information well in advance of the 72-hour threshold and can begin immediately addressing mitigation issues.
Either way, Rapid RH® testing yields this valuable information almost immediately, avoiding costly delays and potentially enhancing project profitability.
The results also further demonstrate the superiority of Rapid RH® testing over MVER via Calcium Chloride (CaCl) testing. Not only does Rapid RH® testing generate scientifically sound data that is essential to successful flooring project outcomes in a way that the CaCl test cannot, but it gives these fully accurate and usable results in a fraction of the time.
Finally, here at Wagner Meters, we are excited about the release of these results, but we aren’t altogether surprised. As many of you know, we have long designed our Rapid RH® system to give you very close readings, generally within ± 3-5% of the final 72-hour reading, within the first hour.
While it has always been possible to predict your final reading almost immediately with our product, these results from the new P&B study can help you fine-tune your initial prediction by the 24-hour mark, adding confidence to your decision and streamlining your project workflow.
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