Rogue River, Ore.—ASTM, the international standards organization, published its revised Standard Test Method for Determining Relative Humidity in Concrete Floor Slabs Using in-situ Probes (ASTM F2170). 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. “Everyone at Wagner Meters is excited about the change to 24 hours, but we weren’t that surprised,” said Jason Spangler, Flooring Division manager at Wagner Meters. “Our own internal testing with the Rapid RH system has long shown essentially identical results between the 72-hour and earlier readings.”
ASTM International updated the industry standard for measuring the moisture condition of concrete slabs in response to an ASTM-commissioned Precision and Bias interlaboratory study conducted in 2014. The 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.
Spangler called the development a “game changer” for flooring professionals. “With the revised F2170 standard, installers can now take action after just one day instead of having to wait three days. 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.”