Rogue River, Ore. -- The international standards organization, ASTM International, published its revised ASTM F2170, Standard Test Method for Determining Relative Humidity in Concrete Floor Slabs Using in situ Probes. The updated standard reduces the mandatory wait period before obtaining official, documentable results from an in situ relative humidity (RH) moisture test performed in concrete floor slabs from 72 hours to 24 hours.

This significant reduction in wait time allows contractors and flooring installers to take action on RH test results a full two days earlier than the ASTM F2170 standard previously allowed. It also should enable contractors and flooring professionals to accelerate their construction and remodeling projects accordingly.

ASTM International updated the industry standard for measuring the moisture condition of concrete slabs in response to an ASTM-commissioned Precision and Bias (P&B) interlaboratory study conducted in 2014. That study documented the temperature and RH readings of in situ RH probes at various times within the old 72-hour window, including at the 24-hour mark. The study's findings confirmed that the readings obtained at 24 hours were statistically equivalent to readings taken at 72 hours.

"What's a game changer for flooring professionals is that with the revised F2170 standard, they can now take action after just one day instead of having to wait three days," said Jason Spangler, Flooring Division manager at Wagner Meters. "No other industry-accepted test method for concrete moisture offers such fast results, and certainly none are more reliable or accurate than the RH test."

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