Lignomat moisture meters have proven measuring technology which guarantees long-term accuracy. Family owned and operated for over 40 years. 

RH BluePeg System

Concrete Moisture Measurement

with RH in-situ probes


    • Removable reusable RH probes
    • One time, low investment
    • Easy to use and easy to read
    • Complies to ASTM standard F2170-11


If too much moisture is inside a concrete slab at the time a floor is installed or coatings are applied, the trapped moisture will eventually travel to the surface and affect the coatings or floor covers. Experts recommend the RH test as the most reliable in-depth measuring method for concrete moisture available today. Using Lignomat’s concrete meters will insure great accuracy, reliability and ease-of-operation.

Overview RH Packages
Contractor Package
Flooring Package
Inspector Package


Watch short video on Lignomat’s RH BluePeg system


Your best choice is the RH Blue Peg System.

No other concrete meter system offers all these advantages:

  • The unique design of the RH BluePeg probes allows for 1 hour quick-test or 72 hour testing (ASTM requirement) or for long-term monitoring.
  • The probes can be removed from the sleeves and reused after each test.
  • The probes are small enough to disappear below the surface of the slab and can be covered by a protective cap between readings.
  • Lignomat’s RH concrete meters are: Ligno-Tec RH, Ligno-DuoTec BW, Ligno-VersaTec Data-loggers are: Memo-Chip BL2 (on-site) and RHTrans (on the Internet)

The one-time, low investment for the RH Packages and the fact that the probes can be used over and over again guarantees the minimum cost per test. There is no need to purchase a new sensor for every test. For calibration requirements see the last paragraph.

Easy to use and easy to read. The RH BluePeg easily fits into the sleeve and is protected by a cap while work can go on around it. Each sleeve comes with a 5/8″ plastic cylinder inside, which positions the probe at the correct distance from the bottom of the sleeve and seals the space between the sleeve and the probe as required by ASTM F2170-11. For measurements the RH cable is connected. The rugged fail-proof connector (same as 3.5mm stereo plug) assures easy handling and a reliable connection. The cable-end-cover secures the probe during measurements. Press the read key on the meter and instantly the RH value and the serial number for the RH Probe are displayed. It is that easy. Anybody can take readings. There is no twisting of a cable or contact alignment necessary. There is no set-up procedure required for the meter and the display is easily read from the meter in your hand. Once the test is completed, connect the cable again and pull the RH BluePeg probe out of the sleeve for the next test.

ASTM Regulations: To comply with the ASTM standard F2170-11, the sleeves or hole liners have to be in the slab for 72 hours before readings are documented. There is no requirement about how long the probes have to be in the sleeve, other than that the readings should be stable.

The RH BluePeg Advantage

If BluePeg probes are left in the sleeves for at least 24 hours, readings are stable and no more acclimation time is needed. If those probes are leapfrogged, stable readings are available within 45 minutes to 1 hour.

You can do quick-checks, 72 hour readings or long time monitoring. You can decide according to job requirements to insert the RH BluePeg probes at the time the sleeves are placed or at any time later. You can leapfrog the probes if you are short on RH BluePegs for the required number of test holes.


The RH BluePeg probe comes with a single microchip sensing element, factory calibrated to NIST-traceable standards. CMOS® technology insures the RH BluePegs highest reliability and long term stability. In addition, the sensing element is covered by a filter that keeps the sensor free of dust at all times for accurate readings.

ASTM regulations require a calibration check 30 days before usage. Using salt solutions is an acceptable method of checking probe calibration. Lignomat offers salt solutions for 33% and 75% relative humidity. Lignomat also offers 3 calibration checks for free during the first year. With this promise, the initial investment in a concrete meter and probes is all that is necessary to take as many tests as necessary within the first year. It is recommended to send the probes in to the manufacturer at least annually for a calibration check.

If you ever have doubts about the calibration or for extremely sensitive testing, you can check the calibration of the RH BluePeg probes before and after test readings have been taken. This is only possible, if the probe is removable.