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Moisture Meters

 

A water restoration job is finished when the moisture meters say the material, that was wet, is now dry.

A thermo-hygrometer provides the Daily Humidity Record information, using psychrometric readings from the air. These can include temperature, relative humidity, humidity ratio (grains per pound), dew point and vapor pressure. 

 

The application, of this information, is discussed in the IICRC WRT class. IICRC Classes Schedule

 

Thermo-Hygrometer.

 

Thermo - heat

Hygro - water

Meter - measure

 

An interesting application of thermo-hygrometers is determining dampness inside a wall. Draw the air out of the wall and measure the grains in the extracted air. A grain reading, comparable to the accepted dry ambient air reading, could indicate it’s dry inside the wall. If you have doubts about the acceptability of the grain outcome, verify with a penetrating meter.... somehow.  

           

 Penetrating Meter

These have pins that push into, wet, material. Electricity moves back and forth across them. Since water is a conductor, it increases the speed of electricity. The amount of liquid and speed of the electricity, gives a % reading.

Temperature can affect our readings. When it’s cool, the speed of the electricity slows and, possibly, gives a lower reading than the actual wetness. Heat will increase the speed of the electric flow and, possibly, give a higher reading than actually exists. Adjustments can be made using charts supplied by the manufacturer. Some moisture meters adjust the reading after the room temperature is typed in.

 

Non Penetrating Meter   

Two non-penetrating units, being used, are the scanner and the percentage reading rubber pad models.

The rubber pad models have two pads that must both touch dampness to give a percentage reading. They are, relatively, unaffected by reflection from ceramic tile, when reading dampness in grout lines. If you clean ceramic tiles, these are great.

The “scanner” is a device that sends radio frequency signals into the wet material, recording the difference in speed when wet. They are a relatively fast way to find dampness that may require further testing, with pins.

 

All moisture meters are useful for water restoration. They each have limitations.

A point of confusion, with scanners. They do not give percentage readings; they give a reading that is a comparison to a larger number.

EXAMPLE: Protimeter scanners are a reading out of a 1,000. They are, generally, used for baseline readings. 85 may be the reading on dry sheetrock. This is 85 out of a possible 1,000. It has nothing to do with percentage. Delmhorst scanners are a number compared to 300. Dry sheetrock could read 25 (just picked a number). This means that with a Delmhorst “scanner” the baseline dry reading, here, would be 25 out of 300.

An example of a wet reading "might be" a number, such as 850 out of 1,000, for the Protimeter and 270 out of 300 for the Delmhorst. (just picked an example)

 

When accurate readings are required, such as a wood cabinet or floor, a penetrating meter is recommended.

 

       MAKE MONEY!

 

       Dennis Klager
       IICRC Instructor

 

 

 

 

  
Copyright 2012 by Dennis Klager