Product Manual

Page 26 of 32

new reading until the SELECT button is pressed and released again during the

reading cycle.

*If the sheathing is plywood, set the meter to the proper species if known. If the

species is unknown, use Douglas Fir. If the sheathing is gypsum material, set the

species to Drywall.

USING 0-100 NUMERICAL REFERENCE SCALE (REL 0-100)

When taking a reading on hard materials such as concrete or masonry, set the meter to

REL 0-100 for a qualitative indication of the moisture level.

Make the best use of reference scale by first establishing a benchmark for the material

you are testing. Take readings in areas that you know are dry, or acceptable. Then take

readings on areas that are wet. These “dry to wet” readings can be used as reference

points against which subsequent readings are compared. Understanding the meter’s

behavior on a particular material, along with these comparative readings, your

experience, and visual clues will all help determine the overall condition. All readings

should be evaluated in the light of factors such as type of paint, type of construction, and

climatic conditions.

The user-selectable alarm will sound if the displayed reading is above the alarm value.

TESTING CONCRETE SLABS FOR FLOORING APPLICATIONS

Moisture meters are an effective tool to check comparative moisture conditions in

concrete slabs. They can tell you where there may be excess moisture and help

determine if you need to conduct further testing, and identify specific areas on which that

testing should be performed. Meters do not provide quantitative results as a basis for

acceptance of a slab for installation of moisture-sensitive flooring systems. ASTM Test

Method F2170 (RH using in-situ probes), F1869 (calcium chloride), and F2420 (RH on

surface using insulated hood) provide quantitative information for determining if moisture

levels are within specific limits.

It is important to test both the surface and mid-section of the slab, especially if the slab is

on or below grade. This will help determine if there is continuous moisture migration

toward the surface. If this condition exists, the moisture movement may be so slow that

once it reaches the surface, moisture evaporates and causes a “dry” reading when a

surface test is made.

However, if a sub-surface test is made, the meter may read “wet” indicating the

presence of moisture. When the slab is covered and the upward movement of moisture

continues, moisture will move into a hygroscopic (wood) floor, or build-up pressure under

a non-breathing synthetic floor, causing delamination.

Taking surface readings:

 Set the meter to PIN mode and the 0-100 Rel scale