Product Manual

Page 27 of 32

 Drive two hardened-steel masonry nails about 3/4" apart into the finish coat of

concrete floor. Drive them about 1/8" deep so they make firm contact with the

concrete and do not move when touch

 Touch the nails with the contact pins.

 Press the select key and read the meter. If the meter reads less than “68”, the

surface is dry. However, sub-surface tests should be made to verify if the slab is

dry throughout.

Taking subsurface readings:

 Drill two 1/4" holes, 3/4" apart and 1/2" to 2" deep.

 Drive the masonry nails into the bottom of the holes and make the tests as

described above. Nails must not touch sides of drilled holes.

If the meter still indicates a “dry” condition, the floor is ready for covering. Tests

should be made at several points, especially when the slab is thick (4” or more)

and air circulation is poor. Make tests only in newly drilled holes.

Even readings in the “wet” range can indicate relatively low moisture content in

Concrete. For example, readings in the “68 to 77” range indicate approximately

2% to 4% moisture content.

When evaluating a slab for readiness, always consider its age, thickness,

whether the slab is on grade or suspended, whether a vapor barrier is present

and the drainage condition of the ground.

SCAN mode may also be used for comparative testing on smooth slab surfaces.

MEASURING RH IN CONCRETE SLABS:

TotalCheck can be used to measure the RH in a concrete slab in accordance with the

ASTM F-2170 Standard Test Method for Determining Relative Humidity in Concrete

Floor Slabs.

Basic Test Procedure:

⇒ Drill a 5/8” hole to a depth of 40% of the slab thckness using a rotary hammer

drill. Use a drill bit specially designed for rotary drills and with 3 or 4 cutting

edges to insure a smooth, round hole. Surface preparation is not required.

⇒ Vacuum the hole thoroughly, then use a wire brush to clean and loosen any

concrete remaining in the hole. Vacuum again and repeat the process a second

time.

⇒ Insert the yellow sleeve into the hole. Use silicone (or other water-resistant

sealant) to seal the interface between the collar of the sleeve and the concrete