How to use a Protimeter Surveymaster

The GE Protimeter Surveymaster has been designed for measuring moisture in buildings utilising dual measuring modes. With its ergonomic design and digital display, this instrument has become the essential tool for building surveyors around the world.

Protimeter Surveymaster’s Dual Measuring Modes

The Protimeter Surveymaster features two modes of operation, search and measure. When utilised together, the dual measuring modes help the user to distinguish the sub-surface moisture from the surface moisture, essential when trying to establish the extent and cause of a dampness problem.

Surface Readings – Two-pin Method

This mode is used to measure the moisture level at the surface and at incremental depth, when used with the auxiliary deep wall probes. Measure mode readings are precise and specific to the immediate area of contact of the electrodes.

Simply hold the instrument with the pins touching the material’s surface and read the moisture level from the LED scale.

A low or no reading will occur if the pins are placed onto a painted or varnished surface. Similarly a covering like vinyl will not hold moisture and provide a low reading.

Be careful not to push the pins into a surface which can be damaged or marked.

Sub-Surface Readings – Deep wall probe method

When determining the sub-surface moisture readings, the surveyors can utilise a set of deep wall probes which connect to the Protimeter Surveymaster through the external auxiliary port.

To use the Deep Wall Probe, drill two clearance holes 1/4 in. (6 mm) in diameter and approximately 1 1/2 in. (40 mm) apart to the required depth.

Connect the Deep Wall Probes to the instrument and push the two probe rods into the clearance holes. Hold the rods firmly against the base of the holes while taking the reading (see photograph).

Sub-Surface Readings – Search Mode

The biggest problem with taking moisture readings, is finding the affected areas, even if the surface has a covering. The search mode provides a non-invasive technique for scanning walls and floors for moisture without damaging the surface.

When held against the surface, as shown, the instrument transmits a signal into the material. The search mode determines the moisture content from the returned signal strength.

The relative moisture level is shown on the digital display and its moisture condition is shown on the accompanying scale of color coded lights.

The nominal depth of the measurement is 3/4 in (19 mm) this depends on the density and other characteristics of the material.

This measurement presentation helps the user to:

• Search for moisture behind wall and floor coverings (tile and vinyl)
• Assess, if the material is in a dry, borderline or damp condition
• Map the extent of the problem numerically
• Finds moisture at depth where moisture is not always directly visible
• This mode of measurement is not adversely affected by the presence of surface moisture

Applications: Shower pans, behind ceramic tile, fine finishes, water stains, tile and vinyl floor coverings, joists, around toilets, drywall, below grade floors and walls, plaster, masonry, concrete and concrete block.

Determining the readings

The Protimeter Surveymaster features a digital LCD display supported by the Protimeters revolutionary colour display which is a collection of 60 LEDs divided into color-coded zones signify moisture readings of the material under investigation. The green, yellow, and red color-coded zones indicate the following:

Depending upon the moisture reading, one of the LEDs will light up to allow the surveyor to read the moisture reading. The scale runs from 6% to 90% WMC (wood moisture content). The WME value is the theoretical moisture level that would be attained by wood that is in moisture equilibrium with the material being tested.

The LEDs are subdivided into three colour zones, green, yellow, and red indicating the severity of the moisture reading. In most cases it is quicker and easier to determine the reading using the colour.

• In the green zone, moisture levels are in a safe air-dry condition
• In the yellow zone, moisture levels are higher than normal but not critical; further investigation is recommended
• In the red zone, moisture levels are excessive and too high. If sustained, high moisture levels will lead to decay

Both the LCD display and coloured LEDs provide accurate readings for both modes of measuring. The LCD display will provide a digital reading of the moisture content to one decimal place whilst the LEDs provide a guide to the severity of the moisture reading.

Two Pin Mode Readings

When reading the damp measurement using the two pin mode (measure), the scale runs from 7% to 99% WMC (wood moisture content). The %WMC has become an industrial recognised reading for moisture whether it’s wood, brick or concrete.

Search Mode Readings

When reading the damp measurement using the search mode, the scale runs from 0 to 999 WME. The higher the moisture content, the higher the reading. Any reading which displays an LED in the red zone, is too damp. The WME value is the theoretical moisture level that would be attained by wood that is in moisture equilibrium with the material being tested.