Wagner Meters Rapid RH 4.0 EX, Руководство пользователя

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elapsed between initially setting up test locations and obtaining the final results per
testing standards, then it is good practice to set a few new tests to confirm and validate
what the older test locations are currently indicating.
Additionally, it is good practice to let the sensors lay on the slab for about 10 minutes or
so prior to installation, until they reach temperature equilibrium with the slab to prevent
any dew point issues that might cause condensation on or around the sensor (NOTE:
Wagner has not heard of any reports where this has actually been an issue, but it is
still a best use practice). For more information on relative humidity in concrete floors
and moisture testing, go to www.cement.org to order the book “Concrete Floors and
Moisture” by Howard Kanare.
*The drying rate of standard Portland cement-based concrete slabs has been studied
extensively. For slabs drying from one side, a very ‘general’ rule-of-thumb as a drying
rate is approximately 30 days of drying time for each inch thickness of the slab for the
relative humidity level to reach somewhere in the 85%-90% range. This is only a very
rough approximate guideline, and drying times can, and often are, much longer if good
drying conditions (closed-in space, environmental controls on, etc) are not present.
Additionally, other factors such as the densifying of a slab surface from heavy power-
troweling, additional water added to the concrete at time of pour, rain or construction
water sitting on a slab, etc, can drastically affect the drying time of a concrete slab.