Electromagnetic Wave Technology Use in Moisture Meters
How Does an Orion Moisture Meter Work?
Wagner Meters uses electromagnetic wave technology in its handheld moisture meters. This technology lets you quickly and accurately measure the moisture content (MC) of wood without the time-consuming effort of driving pins into it. Wagner meters give instant readings, so you can scan many board feet in seconds. Electromagnetic waves are sent into the wood without leaving any holes.
What Is IntelliSense Technology?
Wagner moisture meters with IntelliSense™ technology look beyond surface conditions to measure the moisture IN the wood. Many pinless meters can’t distinguish between surface or ambient conditions on the wood and the actual moisture inside it. Pin-type meters may be able to bypass surface conditions, but they damage the surface of the wood every time you take a reading. Air humidity, condensation, and other ambient conditions can affect many moisture meters and give inaccurate readings that cost you money.
Here’s a short video about Wagner’s moisture meter accuracy:
Pin-Type Meters vs. Electromagnetic Wave: Why Do They Read Differently?
Pin-type moisture meters work on a resistance principle, measuring the flow of electricity through the wood. This method is affected by many variables that can significantly change the readings, such as chemicals in the water in the wood and the wood’s temperature. Most pin-type meter readings must be corrected for wood temperatures above or below 70°F.
The Orion® line of pinless handheld wood moisture meters is virtually unaffected by the temperature of the wood. Wagner Meters uses IntelliSense technology in all of its deep-depth wood moisture meters to minimize the effect of surface moisture on the reading.
Safe to Use
Wagner Meters has tested and certified its moisture meters to comply with FCC and CE requirements.
Moisture Meter Accuracy
The ASTM D4442 oven-dry method is the standard that wood moisture meters are compared against for accuracy.
When compared with that standard, Wagner’s technology has been shown to provide some of the most accurate results in the industry. You can review several university meter studies of Wagner meters.
Wagner Meters Usage Tips
Press down firmly on the meter to make sure the sensor plate has good contact with the wood surface. This is especially important on rough-sawn lumber. Don’t take readings where there’s a noticeable defect or knot in the lumber, and orient the meter in the direction of the grain.
If there’s visible moisture or water on the surface, wipe off any excess and let the surface dry out for a couple of minutes before taking a reading. If possible, turn the board over and measure the other side. If the piece is thicker than 1-1/2 inches, it’s a good idea to take measurements on both sides.
Keep at least a 1-inch air gap under the wood you’re measuring, and make sure nothing (especially your hand or metal) is directly underneath the meter. To take a valid measurement, the meter’s sensing area must be completely covered by the wood you’re measuring. If it isn’t, your MC reading will be inaccurate.
Wood Temperature or Surface Moisture
Moisture meters by Wagner Meters are virtually unaffected by wood temperature.
Standing water or visible water on the board can affect the reading, so wipe off visible water first.
NOTE: If water is allowed to soak into the wood, it will naturally show a higher MC. Rough wood soaks up water readily, which affects the readings of any moisture meter.
Ruggedness
Wagner Meters’ handheld moisture meters are designed for compact convenience. They’re durable, but like any moisture meter, they can be damaged if they’re dropped or slammed down on hard surfaces. For large volumes of wood, an in-line moisture measurement system is a better fit.
Verifying Calibration
Wagner Meters calibrates its moisture meters at the factory, and with proper care, they stay in calibration. If your meter has been dropped, or you suspect for any reason that it’s out of calibration, check it. Orion moisture meters can be checked on the spot with the included On-Demand Calibrator. If you have a legacy meter that can’t be checked in the field, you can buy a calibration verification block. If the meter doesn’t read correctly on the block, send it to the factory for calibration.
Sensing Area
Narrowest Measurement
The Orion sensing area is 2 inches wide by 2.5 inches long, and it must be completely covered by the wood for a valid reading. So the piece you’re measuring needs to be at least 2 inches wide and 2.5 inches long.
Depth of Measurement
The Orion 910 takes moisture readings in wood or other materials from the surface down to .75” (19mm). The Orion 920 is designed exclusively for shallow measurement, from the surface down to .25” (6.4mm). The Orion 930, 940, and 950 measure from the surface down to .25” (6.4mm) or .75” (19mm), depending on whether the meter is set to shallow or deep mode.
If you measure wood thinner than .75” (19mm) in deep mode, the meter will underestimate the actual MC by some amount. Pieces that are only slightly thinner (for example, .625” (15.9mm)) won’t be underestimated substantially, but the thinner the piece, the more the reading will be underestimated. For pieces thinner than .50” (12.7mm), use the shallow mode.
Correct MC
The correct MC varies from region to region and between indoor and outdoor use. Check with local builders or industry associations for the appropriate range in your area, or estimate it for your temperature and humidity with our EMC calculator. If wood is too dry or too wet when it’s glued, the glue joint may not hold.
Resources for determining the proper MC:
- University forestry departments
- Industry associations
- The USDA Forest Products Laboratory in Madison, Wisconsin, 608-231-9200
Frozen or Very Hot Wood
If the wood you’re measuring is frozen or very hot, contact Wagner Meters technical support before relying on the readings, since additional corrections may be needed.
Wet pockets and moisture gradients continually even out as moisture moves from fiber to fiber and into the surrounding air. Moisture meters measure the average of the area scanned. You can hold the meter in one place or slide it along the length of the wood.
Free Download – 5 Ways Pinless Moisture Meters Save You Time and Money
Specific Gravity References
First, check the Species Settings booklet that came with your wood moisture meter. If you can’t find the specific gravity (SG) there, see the Wagner Meters manuals and documentation.
Measuring Non-Solid Wood
Wagner Meters has developed meter settings for the following non-solid wood products, available in the Species Settings booklet. Because of the glues and resins, these give a relative reading.
- Plywood
- OSB
Treated Wood Notes
CCA (chromated copper arsenate)
- Copper: the fungicide, protecting against decay
- Arsenic: the main insecticide
- Chromium: a fixative that binds the other chemicals to the wood
ACQ (alkaline copper quaternary), a copper-based alternative to CCA without arsenic or chromium
- Copper: the primary fungicide and insecticide
- Quaternary ammonium compound: provides additional protection against fungi and insects
Metals and other components in treated wood, including CCA and ACQ, can bias moisture meter readings, so additional corrections may be needed. Pressure treatment forces the preservative solution deep into the wood, so treated lumber can be very wet afterward, and not all treated lumber is kiln dried after treatment.
For the most accurate MC of treated wood, use the oven-dry test.
Wagner Meters is a family-owned American business that aims to provide solutions in moisture measurement technology that will enhance the quality and value of each customer’s project. With an almost 60-year legacy of innovation, Wagner continues to be a resource for both individual craftsmen and high-performance commercial endeavors.
Last updated on October 14th, 2026
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As far as I understand capacitance wood moisture meters are suitable only for perfectly smoth surfaces, and usually used for finished and kiln dryed wood products.
What about these instruments? How useful are they for rough surfaces and high moisture content (not kiln dryed)? I need to measure moisture content in pallets. Do you have scientific research that proves adequacy?
Silvia,
Wagner handheld moisture meters have been used on rough-sawn lumber; a little more pressure needs to be applied. Additionally, neither non-pin (e.g., capacitance) nor pin-type meters should be used where there is a visible knot or defect.
Next, no type of moisture meter is very accurate on wood when the moisture content increases above 30% moisture content.
Wagner has studies showing the accuracy of its moisture meters in moisture content ranges below 30% moisture content.
Where can I gain access to the university meter studies mentioned in the article?
James,
The studies can be found here: https://www.wagnermeters.com/moisture-meters/wood-moisture-training/moisture-meter-accuracy-studies/
Hi – I have a question. Will your moisture meters work with pressure treated fire retardant material? If not, do you know what kind of meter would work and who offers it. Thanks
Barry, yes, the meters will work, but the correct ‘product’ setting may have to be determined by some lab testing. Hoover Treated Wood https://www.frtw.com/?q=about, one of the bigger producers of fire-retardant treated plywood and lumber is a long-time Wagner customer. A study done by them back in 1996, helped them determine the correct correction factor or meter setting to produce the most accurate meter measurements versus the ASTM oven-dry laboratory test.
In short, the meters can provide reliable results with the correct setting.