Expansion Packs (1, 4 and 16 packs available)
Add additional reusable PosiTector CMM IS smart probes as required. Each pack consists of a probe, calibration check chamber, saturated salt solution (NaCl), cap, 2 stackable probe extensions, and A-76/LR-44 coin cell batteries
Replacement chambers, salt solutions, tools, caps and fins are available upon request
1 CMM IS probe
1 Saturated Salt Solution
1 Calibration Check Chamber
2 Stackable Probe Extensions
2 coin cell batteries
4 CMM IS probes
4 Saturated Salt Solutions
4 Calibration Check Chambers
8 Stackable Probe Extensions
10 coin cell batteries
16 CMM IS probes
16 Saturated Salt Solutions
16 Calibration Check Chambers
32 Stackable Probe Extensions
40 coin cell batteries
When mixing concrete, water must be added to create a workable mix, and to allow the cement to hydrate and cure. After hardening, much of this water remains as moisture within the porous concrete slab. Over the following months, this moisture is slowly emitted from the concrete until it eventually equalizes with the surrounding moisture levels.
When applying flooring materials or coatings to concrete, it is critical to ensure that the moisture level inside the concrete has decreased to acceptable levels. If not, moisture can accumulate below the flooring or coating, causing discoloration, cupping, buckling, blistering, adhesive failure, and mold growth. Flooring manufacturers recommend testing concrete moisture levels to verify RH readings are within proper tolerance, before installing a floor system.
ASTM F2170 - Standard Test Method for Determining Relative Humidity on Concrete Floor Slabs Using in situ Probes
As specified in ASTM F2170, in situ concrete moisture meter probes are placed within drilled holes in the concrete. The in situ probe can then measure the relative humidity (RH) and temperature within the concrete floor. In-situ probes directly measure the actual moisture conditions within the concrete using precision digital sensors-regardless of mix, aggregate types, floor thickness, or surface conditions. Potential sources of error are minimized compared to other methods, and in-situ sensors can be calibrated with traceability to national standards.
Several alternate technologies exist for measuring concrete moisture, each with limitations:
Non-destructive electronic concrete moisture meters measure the electrical impedance of the concrete, which is related to moisture levels. However, these meters can be affected by other factors such as variations in concrete composition, and the presence of reinforcing materials. ASTM recommends that these instruments be used as a comparator, and not for determining absolute moisture content.
The anhydrous calcium chloride concrete moisture test involves measuring the increase in weight of salt as it collects moisture from an encapsulated area of the concrete surface. However, significant doubts concerning the accuracy of this test have arisen. There is no practical way to calibrate these kits, they measure moisture only on the surface of the concrete, and they are heavily influenced by ambient conditions.
PosiTector CMM IS probes communicate wirelessly via Bluetooth with either thePosiTector App (iOS/Android) or PosiTector DPM Advanced instruments.
Both solutions offer the ability to wirelessly view and store readings from PosiTector CMM IS probes.
The PosiTector CMM IS has numerous advantages over competitive in situ concrete moisture measurement solutions. Two of the largest innovations are the unique combined sleeve/probe design and being truly wireless; using Bluetooth communication:
DeFelsko recommends storing the PosiTector CMM IS probes in the Calibration Check Chamber when not in use. The Calibration Check Chamber and Saturated Salt Solution are designed in accordance with ASTM E104 to maintain a constant relative humidity environment of 75.3% @ 25° C, allowing quick verification of accuracy before use in accordance with ASTM F2170.
Yes. The Calibration Check Chamber and Saturated Salt Solution were designed to maintain a constant relative humidity (RH) of 75.3% @ 25°C. Relative Humidity (RH) variation due to temperature fluctuation for the Calibration Check Chamber is shown in table 1. When verifying accuracy of PosiTector CMM IS probes, it is important to maintain a constant temperature within the chamber for 24 hours prior to measurement.
A typical battery will continuously power the probe for up to 3 weeks. The battery should be removed when not in use.
Each PosiTector CMM IS probe is calibrated against known conditions using NIST traceable equipment. A Long Form Certificate of Calibration containing actual measured values is included with each probe.
DeFelsko Corporation's standard 2 year warranty applies.
DeFelsko charges $95 for the first three probes, and $30 each probe thereafter. Therefore, the cost to recertify 5 probes is $155 ($95 for the first three probes and $60 for the additional two).
The PosiTector CMM IS measures concrete moisture as described in the ASTM F2170 test Method. It involves drilling a hole into the concrete (generally 40% of the depth of the slab), and using an electronic relative humidity probe to quantitatively measure the moisture directly in the slab. It is a destructive test that requires at least 24 hours of being in-situ before an acceptable reading is taken.
The PosiTest CMM measures concrete moisture as described in the ASTM F2659 test method using a non-destructive electronic impedance meter to instantaneously measure comparative moisture content within the top ¾” of a concrete slab.
Find the following helpful videos and articles to better understand concrete moisture measurement with in-situ probes or concrete moisture meters.
In-Situ concrete RH probe resources:
Concrete moisture meter resources: