MRH III
Non-Destructive Moisture&
Humidity Meter
USER GUIDE
MRH0510
MRH III User Guide
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TRAMEX MOISTURE/HUMIDITY INSTRUMENTS
SURVEY ENCOUNTER: The intelligent moisture meter.
"State of the art" non-destructive moisture meter for measurement and
data logging of moisture in building materials.
MOISTURE ENCOUNTER PLUS
General purpose non-destructive moisture meter employing advanced
analog and digital technology.
CONCRETE ENCOUNTER CME 4
Non-destructive moisture meter for concrete floors.
CRH FLOORING
Non-destructive testing and data logging of moisture content and relative
humidity measurements in concrete (to ASTM F 2170, ASTM F 2420, BS
5325 & 8203), gypsum screeds and sub-floors.
CMEXPERT FLOORING INSPECTION KIT
Complete kit for moisture testing of concrete, hardwood flooring and sub-flooring. Can also be used for relative humidity testing of flooring by either the
in-situ probe method (ASTM F 2170) or the RH hood method (ASTM F 2420,
BS 5325 and 8203).
PROFESSIONAL MOISTURE METER
Digital resistance meter with probes, tests deep into wood.
COMPACT MOISTURE METER
Economical pin-type resistance meter for wood.
SKIPPER PLUS
Checks wooden boats for decay and finds osmosis in GRP.
DEC SCANNER
Mobile non-destructive surveying of flat roofs.
WET WALL DETECTOR
Non-destructive moisture evaluation and tracing in EIFS.
RWS ROOF AND WALL SCANNER.
For moisture scanning and leak tracing on roofing, EIFS and the building
envelope.
MOISTURE & HUMIDITY INSPECTION KITS ARE AVAILABLE FOR
THE FOLLOWING INDUSTRIES:
Floor inspection / EIFS wall inspection / Roof inspection / Indoor Air Quality /
Water damage restoration.
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Introduction................................................................... 4
How it works ................................................................. 4
Instrument Features ................................................ 6
Operating Instructions ............................................. 8
Non-destructive measurement mode................. 9
Wood pin meter mode ............................................ 10
Typical MRH Displays ........................................... 12
Humidity measurement mode ............................ 14
Working with your MRH...................................... 14
................................................................ 14
....................................................... 15
.......................................................... 16
...................................................... 17
............................................................. 17
Wood Pin Meter Mode ........................................... 24
RH Probe....................................................................... 40
.................................................................... 41
Warranty....................................................................... 42
.......................................... 28
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Thank you for selecting a new MRH instrument fromTramex.
The MRH has 3 modes of operation:
1: The MRH utilises “state of the art” electronic technologyto provide you with an accurate and easy to use non-invasiveinstrument for non-destructive testing (NDT) of MoistureContent (MC) and tracing moisture in a wide range ofbuilding materials. 2: By inserting one of the optional plug-in electrodes forwood and selecting Pin Probe the instrument can then be usein Pin Probe (wood pin-meter resistance measurement)Mode. This enables the MRH to measure the percentagemoisture content (%m.c.) of wood and give an indicationof the moisture content of wood-based products.
3: By inserting the optional plug-in RH-probe, theinstrument automatically changes to hygrometer mode. Thisenables the MRH to measure relative humidity (RH),temperature, dew-point temperature and mixing ratio ofthe environment or equilibrium relative humidity in astructural material. A structural material such as a concreteslab can be tested using the in-situ (ASTM F2170) or RHHood (ASTM F2420) methods and British standards BS5325 and BS 8203.
In non-destructive moisture measurement mode i.e.without the plug in probes, the instrument operates on theprinciple that the electrical impedance of a material varieswith its moisture content. The electrical impedance is
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AlternatingElectric Field
Materialunder testTransmit &
ReceiveElectrodes
MRH
measured by creating a low frequency alternating electricfield between the electrodes as illustrated in Figure 1 below.
This field penetrates the material under test. The very smallalternating current flowing through the field is inverselyproportional to the impedance of the material. Theinstrument detects this current, determines its amplitude andthus derives the moisture value.
Figure 1
In Pin Probe Mode (i.e. with pin probe mode selected andan electrode plugged in), the MRH is a resistance type pinmeter for determining the percentage moisture content ofwood.
In Hygrometer mode (i.e. with the RH Probe plugged in),the MRH determines the capacitance of the RH probesensor, which varies with the relative humidity of the testarea environment. The MRH displays this capacitance aspercentage relative humidity (%RH). It also measurestemperature and displays dew-point temperature and mixingratio.
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Your MRH employs advanced digital technology to enablethe incorporation of many features, which are listed below.
3 modes of measurement: Non-destructive moisturemeasurement, hygrometer and wood pin probe.6 simple membrane keypad controls:
ON/OFF
SCALE
UP
DOWN
HOLD/AUDIO
BACKLIGHT
5 Scales: Wood, Roof, Masonry, Drywall and Laminate.These are selected using the key and the or keys.
Moisture readings and scale are displayed on a cleareasy to read liquid crystal display (LCD).
Relative Humidity (RH) readings, probe temperature,dew-point temperature and mixing ratio areautomatically displayed when the RH Probe is pluggedinto the MRH (Hygrometer Mode).
The Roof, Masonry, Drywall and Laminate Scales use areference/comparative scale that is displayed bothnumerically (0-99) and in a bar form on the bottom lineof the display. The display also shows low (LO),medium (MD) and high (HI) readings for these scales.
These do not necessarily indicate low, medium or high levels of moisture but indicate the area of the 0-100 comparative scale where the reading lies.
Example
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To conserve battery life, the instrument automaticallypowers OFF after 10 minutes of inactivity or when the
key is pressed. If a key is pressed the power off will
Backlit display allows the display to be easily read inpoor light conditions. This is enabled by pressing the
key. The backlight stays on for a period of 30seconds.
When the battery requires replacement a LOWBATTERY message is shown on the LCD.
HOLD freezes reading to facilitate ease of recordingreadings. When the MRH is in HOLD mode, ‘H’ willflash on the display.
If HOLD was selected prior to the MRH automaticallypowering off, the frozen display reading is digitallymemorized and restored next time ON is selected.
will be extended for an additional ten minutes.
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Operating Instructions
Figure 2
A diagram of the instrument face with brief notes on thepush button controls and LCD is shown above (Figure 2).
TM
W OO D H
S G . 5 8 M C 0 5 . 9 %
MRH III
PhonoSocketfor WoodProbes
LIGHTKEY
HOLD/AUDIOKEY
RH ProbeSocket
SCALEKEY
UP / DOWNKEYS
Flashing‘H’ in HoldMode
ON/OFFKEY10 minute switch off
BACKLITDISPLAY
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Non-destructive measurement mode
1. Press the key to power up. With no RH probe or pinprobe connected the last used scale will be displayed on
the LCD. Press key again to power off.2. To change scale, press key to select the wood scale
or the comparative material scales. Select the requiredmaterial scale using the or key.
3. Hold your MRH directly on the wood, roof, masonry,drywall or other material being tested, ensuring bothconductive-rubber electrodes are fully in contact withthe surface.
4. For the Roof, Masonry, Drywall and Laminate scalesthe readings are comparative from 0 to 99. A visualindication is also given by the bar display on the bottomline of the LCD. The display also shows low (LO),medium (MD) and high (HI) readings for these scales.LO is displayed for readings from 0 to 30, MD forreadings from 31 to 70 and HI for readings from 71 to 99.
5. The readings on these scales are not to be interpreted asa measurement of percentage moisture content (% MC)or relative humidity (RH). It is not a relative humidityreading and it does not have any linear correlation withRelative Humidity measurements. This scale should beregarded as a comparative or qualitative scale only.
6. When the Wood Scale is selected the moisture content(MC) in percent of wood is shown on the right-handside of the bottom line of the display. The left-hand sideof this line shows the specific gravity (SG) being used.
The SG is changed by using the or key to adjustto the required SG value. The range of SG covered is0.30 to 0.80. The S.G. increases and decreases inincrements of 0.01
7. A chart showing the approximate specific gravity of awide range of different species is shown on pages 22
These do not necessarily indicate low, medium or high levels of moisture but indicate the area of the 0-100 comparative scale where the reading lies.
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and 23. For SG greater than 0.80 please refer to speciesadjustment table (Table 2 on Page 20).
8. To turn audio tone on or off, press key twice inquick succession.
9. The MRH will automatically power-off after tenminutes if no key is pressed. If a key is pressed thepower-off will be extended for an additional ten minutes.
10. To freeze readings press the key once. While onHOLD, H will flash slowly on the upper line of thedisplay. If the unit powers OFF while on HOLD, thefrozen meter reading is digitally memorized andrestored next time ON is selected. To remove freeze,press key again.
Wood pin meter (Pin Probe) mode
This mode is activated by plugging one of the optionalWood Electrodes into the socket at the top of the instrumentand selecting Pin Probe using the key. In pin probe modethe MRH works on the principle of electrical resistance.When the electrode pins are pressed or driven into the wood,the electrical resistance between the electrodes is measuredand indicated on the digital display. If the wood is dry, theresistance is very high. The higher the moisture content, thelower the resistance. This resistance is accurately measuredby the instrument, which translates it into percentagemoisture content for wood. The MRH gives moisturereadings from 7% to 40%. It should be noted that readingsabove 27% (nominal value of the fibre-saturation point) areindicative only.
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Wood Pin Meter Mode Vs. Non-DestructiveMeasurement ModeThe two main types of moisture meter for measuringmoisture content in wood are the pin type meter and the non-destructive or impedance type meter. Both types arecalibrated using gravimetric or oven-drying test methods.The Tramex MRH combines both of the above methodsin one instrument so it is important to understand howeach test method works as the results from the two testsmay sometimes be different and appear to becontradictory.
The pin type meter measures the resistance between twopins, which are inserted into the timber. The standardcalibration for this type of meter is based on a Douglas Firwith a specific gravity (S.G.) of 0.5.The impedance or non-destructive type meter has twoelectrodes, which transmit a low frequency signal into the
takes an average reading over a much larger area but theS.G. of the material being tested affects the reading more.
On the MRH non-destructive test it is possible to adjust thespecific gravity for better species-dependant readings if thematerial is of sufficient thickness. If the SG of the material isnot known it is possible to use the readings from the pinmeter to give an approximation of the SG for the non-destructive meter. This is done by Adjusting the SG on thenon invasive test until both tests give approximately thesame reading. This is not as accurate as knowing the exactS.G. of the material but can be a good indication.
It is very important to note that the readings of the non-
(30mm) thick it is possible to get false readings from anothermaterial in contact with it. A typical example of this wouldbe a laminate floor over concrete.
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Humidity Probe Display
METRIC
Flashing 'H' in Hold mode
Relative Humidity T ºC
R H 5 0 . 1 % H T 2 0 C
T d 1 1 . 7 C 0 0 0 7 g m s
Dewpoint (Td) ºC Mixing Ratio g/kg
IMPERIAL
R H 5 0 . 1 % H T 6 8 F
T d 5 3 . 1 F 0 0 5 1 G R N
Wood Pin Probe Display
P I N X X X X X X X X
P R O B E M C = 1 0 . 8 %
Moisture Content
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The optional Relative Humidity (RH) Probe can be pluggedinto the socket at the top of the instrument. The displayshows relative humidity (RH), temperature (T), dew-pointtemperature (Td) and mixing ratio in grains/lb (GRN) org/kg (gms). When the RH Probe is plugged into the MRH,the or key is used for changing the temperaturebetween ºC and ºF and the mixing ratio between g/kg andgrains/lb.
The MRH has 4 comparative material scales: Roof,Masonry, Drywall and Laminate. The comparative materialscales are selected using the key and switching between
the various scales using or key.
a) The presence of moisture in built-up roofs covered withmulti-ply roofing felt, PVC, modified bitumen and allnon-conductive membranes (See Limitations Section),can cause blistering and splitting of the roof covering. Inaddition moisture can cause considerable damage to thecontents and fabric of the building as well as heat lossthrough wet insulation. Your MRH can be used toconfirm a new roof has been installed dry and help traceleaks.
b) If the waterproofing membrane develops a leak, thewater can travel within the built-up-roof structure and
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enter the building some distance away. Testing themembrane surface and comparing the dry areas withareas where moisture is present below the surface canassist in tracing such a leak to its source.
c) As there are many different types and thickness sizes ofroofing membranes, it is not possible to give acalibrated percentage measurement. Instead, a comparativescale is displayed both numerically, (0 to 99) and in a bar form on the bottom line of the display. The display alsoshows low (Lo), medium (Md) and high (Hi) readings for the scale.
d) If gravel surfacing is present, this should be removed toensure your MRH comes into direct contact with thesurface of the membrane.
e) It is recommended that a core be cut to determine thedepth and density of the moisture before carrying outroof repairs. Alternatively, the area can be checked witha resistance-type moisture meter with insulated pins upto a length of 7”(180mm).
Your MRH gives comparative (relative) readings (0 to 99)on plaster, brick and block. These readings are displayed both numerically and in bar form on the LCD. The display alsoshows low (Lo), medium (Md) and high (Hi) readings for the scale.
For plaster, brick and block use the Masonry scale. For Drywallthe more sensitive dedicated Drywall scale is used. Alwayspress the electrodes firmly against the surface.
The moisture profile of a masonry wall can be determinedby moving your MRH across the surface where it will readthrough most paints and wall coverings.
It will help identify the different levels of moisture even ifnot apparent on the surface. Moisture can often be trappedbehind wall coverings.
These do not necessarily indicate low, medium or high levels of moisture but indicate the area of the 0-100 comparative scale where the reading lies.
These do not necessarily indicate low, medium or high levels of moisture but indicate the area of the 0-100 comparative scale where the reading lies.
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Rising damp and moisture migration from leaks anddefective, or non-existent, vapor barriers can be identifiedand profiled and often its source identified by moving theinstrument across the wall surface.
Water damage following flooding or fire fighting can bechecked and the drying out and de-humidification processcan be monitored.
Because of its deep signal penetration, your MRH canidentify excess moisture behind drywall, ceramic tile andother wall coverings when used on the Drywall Scale.
.
Excess moisture trapped behind covering materials such asceramic tiles, carpet, wall coverings etc can cause majorproblems. For instance, excess moisture behind ceramic tileson drywall or other substrates can cause decay, delaminationand mold growth. The longer these problems go undetected,the worse the problem can get, eventually leading to systemfailure.Your MRH can be used to detect and identify areas ofelevated moisture within or behind most types of wall andfloor coverings. For example the MRH can detect elevatedmoisture behind most types of ceramic tiles.
Should the Drywall Scale prove to be too sensitive fortesting ceramic tiles or other coverings, reduce sensitivity bychoosing the Laminate Scale and take readings on acomparative basis.
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For applications where the Roof or Drywall scales are toosensitive and the Masonry scale is not sensitive enough, theLaminate scale can be used. This scale used can be used fortesting on ceramic tiles and other wall and floor coverings. Itcan also be used in many other applications where the otherscales do not have the required sensitivity.
a) When testing wood, power-on, select Wood Scale usingthe key.
b) When the Wood Scale is selected the moisture content(MC) in percent is shown on the right-hand side of thebottom line of the display. The left-hand side of this lineshows the specific gravity (SG) being used. See note onspecific gravity on page 23. The SG is changed by usingthe or key to adjust to the required SG value. The range of SG covered is 0.30 to 0.80. The S.G.increases and decreases in increments of 0.01.
c) A chart showing the approximate specific gravity of arange of different species is shown on pages 22 and 23.For SG greater than 0.80 please refer to specific gravityadjustment chart (Table 2 on page 20). For species notlisted a more comprehensive list is available on theUSDA website www2.fpl.fs.fed.us/ (in the US) orfrom timber importers and forestry departments in othercountries.
d) If possible, always take readings with the length of theinstrument parallel to the direction of the wood grain.
e) Calibration tests were carried out by Forbairt, the IrishInstitute for Industrial Research and Standards, and arebased on Douglas Fir, which had a published specificgravity (SG) of 0.50.
f) Acceptable levels of moisture content depend onclimatic conditions and we advise you check the levelsacceptable in your area. Table 1 on page 19 shows the
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approximate relationship between the ambient relativehumidity and equilibrium moisture content in woods.
g) The following moisture content levels are given as aguide
Furniture: 5% to 6% when used in locations of lowrelative humidity and up to 10% to 11% may beacceptable where the relative humidity is higher.Interior wood: 6% in low humidity areas. Up to12% in higher humidity locations.Exterior wood: 10% to 15% depending on localhumidity levels.Generally, wood with a moisture content in excessof 23% - 25% is susceptible to rot.Wood moisture content in excess of 18% - 20%may provide an environment for termite and wood-boring insects to thrive and multiply. Wood at thesehigh levels can also support mold and biologicalgrowth.Wood at 28% moisture content is considered tohave reached fiber saturation point.
h) Avoid taking readings on wood from the top of a stackstored outside as these may be affected by surfacemoisture from recent rain.
i) When taking readings in chemically treated wood, it isadvisable to allow for possible effects that the treatmentmay have on readings.
The following table shows the approximate relationshipbetween relative humidity (RH) and equilibrium moisturecontent (EMC) of some woods.These figures are approximate values and may vary fordifferent species.
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10% 3 to 520% 5 to 630% 6 to 840% 8 to 1050% 10 to 1160% 11 to 1370% 13 to1580% 15 to 1890% 18 to 23
100% 23 +
Depth of field penetrationDepending on the density of the material being tested, the instrument field can
thin materials such as wood veneers it is recommended that they are stacked to atleast that thickness.
a) Excess moisture in wood flooring or concrete sub-floorscan cause major problems. For instance, if installed withexcess moisture, the wood can subsequently shrinkleading to job failure.
b) If a wood floor (solid, laminated or engineered) isinstalled above wet concrete the wood can absorbmoisture emitting from the concrete causing the wood toswell and buckle and even cause structural damage tothe building. For measuring the moisture in concrete,the Tramex CME4, CRH or CMEXpert should be used.
c) Your MRH can be used to measure the moisturecontent of the wood floor to ensure it meetsspecification. Likewise it can be used to check, on acomparative basis, through the floor covering, toidentify elevated moisture in the substrate.
Relative Humidity Wood MC %
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NOTE: On the Wood, Drywall, Roofing andLaminate Scales the depth of penetration of
When using any of these scales on wood orlaminate over concrete or other screeds, theMRH will be reading through the materialand may be giving a much higher thanexpected reading. This is invariably due to the fact that concrete is a much densermaterial than wood or wood-based products.In such instances, the wetter areas can beidentified non-invasively and the wood probecan then be used to make select intrusions todetermine the moisture content of the wood orlaminate.
.G.SReading 0.85 0.9 0.95 1
S.G. set at 0.5 Adjustment.5 to 9 -3 -4 -4 -4
10 to 12 -4 -5 -5 -513 to 15 -5 -6 -6 -616 to 18 -6 -7 -7 -819 to 21 -7 -8 -9 -1022 to 24 -9 -9 -11 -1125 to 27 -11 -11 -12 -1328 to 30 -12 -13 -13 -1431 to 33 -14 -14 -14 -1534 to 36 -15 -15 -15 -16
Table 2. Specific Gravity Adjustment Table (S.G. > 0.80)
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AdhesivesThe presence of different species, treatments, adhesives, etc.,within products such as plywood, particleboard, OSB(oriented strand board), laminated and engineered woodswill affect measurements. If in doubt please contact us and,if you wish, we can work with you in developing your owncalibration for a specific product.
Concrete.Your MRH is not calibrated for concrete. The TramexConcrete Encounter CME4, CMExpert and CRHinstruments are specifically designed for concrete flooringand are recommended where quantitative measurements arerequired. However a comparative indication of the moisturecondition of a concrete or sub floor can be obtained with theMRH set on the Masonry scale. Comparative readings canalso be obtained through coverings such as vinyl, carpet andlaminated wood flooring by using the Laminate Scale.
Chemical treatment or contaminationReadings may be affected by certain flame-retardants,preservatives, aluminium paint and by contamination by saltwater. Treat all readings on such wood as indicative readingsonly.
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Table of Wood Specific Gravities (S.G.) HARDWOODS Am. = American Alder, Red (Am. Alder, Western Alder) Alnus rubra 0.41 Ash, White (Northern / Southern Ash) F. americana 0.60 Aspen, Quaking (Am. Aspen) Populus tremuloides 0.38 Basswood (Am. Basswood, Linden) Tilia americana 0.37 Beech Fagus Grandifolia 0.64 Birch, Yellow (Gray, Silver, Swamp)B. alleghaniensis 0.62 Cherry (Am. Black Cherry) Prunus serotina 0.50 Cottonwood (Eastern Cottonwood) Populus deltoides 0.40 Elm, Red (Slippery elm) Ulmus rubra 0.53 Hackberry (Common Hackberry) Celtic occidentalis 0.53 Hickory (Pignut, True Hickory) Carya glabra 0.75 Maple, Am. Hard (Sugar Maple) Acer saccharum 0.63 Maple Am. Soft (Red Maple) Acer rubrum 0.54 Maple, Silver Acer saccharinum 0.47 Maple, Black Acer nigrum 0.57 Oak, Northern Red Quercus rubra 0.63 Oak, Southern Red (Cherrybark) Quercus falcata 0.68 Oak, White (Am. White Oak) Quercus alba 0.68 Pecan Hickory (Am. Pecan) CaryaiIllinoensis 0.66 Red Gum (Sweetgum) Liquidamber styraciflua 0.52 Sassafras (Golden Elm) Sassafras albidum 0.46 Sycamore(Am. Planetree, Buttonwood) P. occidentalis 0.49 Walnut, Black (Am. Walnut) Juglans nigra 0.55 Willow, black (Am. Willow) Salix nigra 0.39 Yellow Poplar (Am. Tulipwood, Tulip Poplar, Canarywood)
Liriodendron tulipifera 0.42
SOFTWOODS Cedar, Alaska (Alaskan Yellow) 0.44
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Cedar, Incense 0.37Cedar, Port-Orford 0.43Cedar, Western Red 0.32Douglas Fir, Coast 0.48Douglas Fir, Interior West 0.50Fir, California Red 0.38Fir, Grand 0.37Fir, noble 0.39Fir, Pacific Silver 0.43Fir, White 0.39Hemlock, Western 0.45Larch, Western 0.52Pine, Lodgepole 0.41Pine, Ponderosa 0.40Pine, Sugar 0.36Pine, Western White (Idaho) 0.38Spruce, Engelmann 0.35Spruce, Sitka 0.40
EXOTIC
Balsa 0.16Ebony 1.10Karri 0.82Padauk 0.77Tulipwood 0.96Source: USDA: Wood Handbook 1987.
Note on specific gravity (S.G.):The specific gravity (S.G.) of wood is the ratioof the density of wood to the density of waterat a specified temperature (generally 4ºCwhere the density of water is at its maximum).The density of wood is usually based on theoven-dry weight and the volume at thespecified moisture content (M.C.), generally12%.
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Factors Affecting Moisture ReadingsThe readings of all moisture meters are influenced by thecharacteristics of different species of wood as well astemperature and other factors listed below.SpeciesDifferent species of wood can vary in density andconductivity, which can have an effect on the electricalresistance of the wood. This can influence meter readings forthe same moisture content and can also apply to similarspecies from different origins. A species adjustment table isprovided on page 28 to 39.TemperatureMeter readings can be affected by wood temperature. TheWood Probe is calibrated at 20 C (68 F). At woodtemperatures above 20 C (68 F), the meter readings arehigher and at wood temperatures below 20 C (68 F) themeter readings are lower. A temperature adjustment chart isprovided on page 27.Chemical treatment or contaminationReadings may be affected by certain flame retardants,preservatives, aluminium paint and by contamination by saltwater. Treat all readings on such wood as indicative readingsonly.
Surface MoistureSurface moisture due to wetting or condensation can affectreadings when uninsulated pins are used. It is recommendedthat insulated pins such as SP-52 are used in conjunctionwith HA-22 Hammer Action electrode. As the pins are
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driven into the wood, readings can be taken at differentdepths unaffected by moisture on the surface.
Wood Flooring
a) Excess moisture in wood flooring can cause majorproblems.
b) For instance, if installed with excess moisture, the woodcan subsequently shrink leading to job failure.
c) If a wood floor (solid, laminated or engineered) isinstalled above wet concrete the wood can absorbmoisture emitting from the concrete causing the wood toswell and buckle and even cause structural damage tothe building.
d) Your MRH in PIN Probe mode can be used to measurethe moisture content of the wood floor to ensure it meetsspecification.
Testing wood and wood products
a) When testing wood, power-on, insert wood probeinto phono-socket at the top of the MRH andselect Pin Probe Mode using the key.
b) When a wood probe is inserted the moisturecontent (MC) in percent is shown on the right-hand side of the bottom line of the display.
c) If possible, always take readings with the pinsparallel to the direction of the wood grain.
d) Calibration tests are based on Douglas fir, whichhas a published specific gravity (SG) of 0.50.
e) Acceptable levels of moisture content depend onclimatic conditions and we advise you check thelevels acceptable in your area. Table 1 on page19 shows the approximate relationship betweenthe ambient relative humidity and equilibriummoisture content in woods.
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f) The following moisture content levels are oftenquoted in the wood industry and should be usedas a guide only. Please contact industryassociations and manufacturers for theirspecifications.
Furniture: 5% to 6% when used in locations of lowrelative humidity and up to 10% to 11% may beacceptable where the relative humidity is higher.Interior wood: 6% in low humidity areas. Up to12% in higher humidity locations.Exterior wood: 10% to 15% depending on localhumidity levels.Generally, wood with moisture content in excess of23% - 25% is susceptible to rot.Wood moisture content in excess of 18% to 20%may provide an environment for termite and wood-boring insects to thrive and multiply. Wood at thesehigh levels can also support mold and biologicalgrowth.Wood at 28% moisture content is considered tohave reached fiber saturation point.
g) Avoid taking readings on wood from the top of astack stored outside as these may be affected bysurface moisture from recent rain.
h) When taking readings in chemically treatedwood, it is advisable to allow for possible effectsthat the treatment may have on readings.
Temperature Adjustment ChartThe Pin Probe has been calibrated on wood at an ambienttemperature of 20 C (68 F). When measuring moisture inwood at a different temperature, the following temperatureadjustment needs to be applied. (Figures rounded to thenearest whole number).
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Example 1:If meter reads 15% and temperature of woodis 10 C (50 F), actual moisture content is17%. i.e.15%+2%=17%
Example 2:If meter reads 15% and temperature of wood is 50 C(122 F), the actual moisture content is 11%. i.e.15%-4%=11%
Combined Species/Temperature CorrectionExample 1If meter gives reading 15% on a sample of Sitka Spruce andthe wood temperature is 40 C, the correction is as follows:Species correction @15% = 16%Temperature correction @ 40 C = - 3%Corrected reading: 13%Example 2If meter gives reading 24% on sample of Teak and the woodtemperature is 10 C, the correction is as follows:Species correction @24% = 20%Temperature correction @ 10 C = + 2%Corrected reading: 22%
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7 9 7 9 9 9 8 9 5 7 9 9 7 9 7 8 8
8 10 7 10 10 10 9 10 6 8 10 10 8 10 8 9 9
9 10 8 11 11 10 10 11 7 9 11 11 9 11 10 10 10
10 11 9 12 11 11 11 12 8 10 12 12 9 12 11 11 11
11 12 9 13 12 12 12 13 9 11 13 13 10 13 12 12 11
12 13 10 14 13 12 12 14 10 12 14 14 11 14 13 13 12
13 13 11 15 14 12 13 15 11 13 15 15 11 15 14 14 13
14 14 12 16 14 14 14 16 12 14 15 16 12 16 15 15 14
15 15 12 17 15 14 14 17 13 15 16 17 13 16 16 16 14
16 15 13 18 16 15 15 18 14 16 17 18 13 17 13 17 15
17 16 14 18 17 16 16 18 15 17 18 19 14 18 18 18 16
18 17 14 19 18 17 17 19 16 18 18 20 15 19 19 19 17
19 18 15 20 19 17 18 20 17 19 19 22 15 20 20 20 18
20 18 16 21 20 18 18 21 18 20 20 23 16 21 21 21 18
21 19 17 22 21 19 19 22 19 21 21 24 17 22 23 22 19
22 20 17 23 23 20 20 23 20 22 22 25 17 23 23 23 20
23 20 18 24 24 20 21 24 21 23 23 26 18 24 24 24 21
24 21 19 25 25 21 21 25 22 24 24 27 18 25 25 25 22
Cor
rect
moi
stur
eco
nten
t
28
III
Met
erre
adin
g(%
moi
stur
eco
nten
t)
Spec
ies
Bee
ch,s
ilver
Bee
ch,W
auB
eech
,whi
teB
irch
,Eur
opea
nB
irch
,whi
teB
lack
butt
Bla
ckbu
tt,W
AB
lack
woo
dB
lood
woo
d,re
dB
olly
woo
dB
ox,b
rush
Box
,gre
yB
ox,g
rey,
coas
tB
ox,k
anuk
aB
row
nbar
rel
7 9 9 8 7 9 8 9 9 10 7 7 10 9 8 7
8 10 11 9 8 10 9 10 9 10 8 7 11 10 9 8
9 10 12 10 10 11 10 11 10 11 9 8 12 11 10 9
10 11 13 11 11 12 11 12 11 12 10 8 12 11 11 10
11 12 14 12 12 12 12 12 12 13 11 9 13 12 12 11
12 12 15 13 13 13 13 13 12 14 12 9 14 13 12 12
13 13 16 14 14 14 14 14 13 15 12 10 14 14 13 12
14 13 17 14 15 15 15 15 14 15 13 10 15 14 14 13
15 14 18 15 16 15 16 16 15 16 14 11 16 15 15 14
16 14 19 16 17 16 17 17 16 17 15 11 17 16 16 15
17 15 20 17 18 17 18 18 16 18 16 12 17 17 16 16
18 16 21 18 19 18 19 19 17 19 16 13 18 18 17 17
19 16 22 19 20 18 20 20 18 19 17 13 19 18 18 18
20 17 23 19 21 19 21 21 19 20 18 14 20 19 19 18
21 17 24 20 22 20 22 22 20 21 19 14 20 20 20 19
22 18 25 21 23 21 23 23 20 22 20 15 21 21 20 20
23 19 26 22 24 22 24 24 21 23 21 15 22 22 21 21
24 19 27 23 25 22 25 25 22 23 22 16 23 22 22 22
Cor
rect
moi
stur
eco
nten
t
29
III
Met
erre
adin
g(%
moi
stur
eco
nten
t)
Spec
ies
Buc
hana
nia
Can
dlen
utC
arab
een,
yello
wC
edar
,red
Ced
ar,r
ed,w
este
rnC
edar
,Sou
thA
mer
ican
Che
rry
Coa
chw
ood
Dak
uasa
lusa
luD
ougl
asFi
rE
lmE
rim
aFi
r,A
lpin
eFi
r,am
abili
sFi
r,re
d
7 6 5 8 9 7 9 6 9 7 6 8 8 8 8
8 7 8 9 10 9 10 7 10 8 7 8 9 9 9
9 8 10 9 11 10 11 8 11 9 7 9 10 10 10
10 9 12 10 12 11 12 9 11 10 8 10 11 11 11
11 10 14 11 13 12 13 10 12 11 9 11 12 12 12
12 10 16 12 14 13 13 11 13 12 10 12 13 13 13
13 11 18 12 16 13 14 12 14 13 12 12 14 14 14
14 12 21 13 17 14 15 13 15 14 13 13 15 15 15
15 13 23 14 18 15 16 14 16 15 13 14 16 16 16
16 14 25 14 19 17 17 14 17 16 14 15 17 17 17
17 14 27 15 20 18 17 15 18 17 15 15 18 18 18
18 15 29 16 21 19 18 16 19 18 15 16 19 19 19
19 16 31 16 22 20 19 17 19 19 16 17 20 20 20
20 17 34 17 23 21 20 18 20 20 17 18 21 21 21
21 18 36 18 25 22 21 19 21 21 18 19 22 22 22
22 19 38 18 26 23 22 20 22 22 19 19 23 23 23
23 19 40 19 27 24 22 21 23 23 20 20 24 24 25
24 20 42 20 27 25 23 22 24 24 20 21 25 25 26
Cor
rect
moi
stur
eco
nten
t
78
911
1213
1415
1617
1818
2021
2223
2125
Che
rry,
Bra
zilia
n7
89
1112
1314
1516
1718
1820
2122
2321
25
30
III
Met
erre
adin
g(%
moi
stur
eco
nten
t)
Spec
ies
Fir,
whi
te
Gum
,blu
e,so
uthe
rnG
um,b
lue
Tasm
ania
nG
um,g
rey
Gum
,gre
y,m
ount
ain
Gum
,lem
on-s
cent
edG
um,M
aide
ns
Gum
,man
naG
um,m
ount
ain
Gum
,Am
eric
an,r
ed
Gum
,red
,riv
erG
um,r
ose
Gum
,shi
ning
Gum
,yel
low
7 8 9 8 8 9 6 10 7 6 10 10 9 8 9
8 9 10 9 8 9 7 11 7 7 11 11 10 9 10
9 10 11 10 9 10 8 11 8 8 12 12 11 10 11
10 11 12 11 10 11 9 12 9 9 12 13 12 11 12
11 12 13 12 11 12 10 13 10 10 13 14 13 11 12
12 13 14 12 12 13 10 14 11 11 14 15 14 12 13
13 14 15 13 13 14 11 15 12 12 15 16 14 13 14
14 15 15 14 14 14 12 16 13 13 16 17 15 14 15
15 16 16 15 15 15 13 16 14 14 17 18 16 15 15
16 17 17 16 16 16 13 17 14 15 18 19 17 16 16
17 18 18 17 17 17 14 18 15 16 18 20 18 17 17
18 19 18 17 18 18 15 19 16 17 19 21 18 18 18
19 20 19 18 19 19 16 20 17 18 20 22 19 19 18
20 21 20 19 20 19 17 20 18 19 21 23 20 20 19
21 22 21 20 21 20 17 21 19 20 22 24 21 20 20
22 23 22 21 22 21 18 22 20 21 23 25 22 21 21
23 25 23 22 23 22 19 23 21 22 24 26 23 22 21
24 26 24 22 24 23 20 24 21 23 24 27 24 23 22
Cor
rect
moi
stur
eco
nten
t
31
III
Met
erre
adin
g(%
moi
stur
eco
nten
t)
Spec
ies
Hem
lock
,wes
tern
Hic
kory
Irok
oIr
onba
rk,r
edIr
onba
rk,r
ed,b
road
-lea
ved
Iron
bark
,red
,nar
row
-lea
ved
Jarr
ahJe
luto
ngK
amar
ere
(PG
Nso
urce
)K
amar
ere
(Fiji
sour
ce)
Kap
urK
arri
Kau
ri,Q
ldK
auri
,NZ
Kau
ri,V
anik
oro
7 8 - 7 11 11 8 8 8 8 7 7 7 10 9 11
8 9 7 7 12 12 9 9 9 9 8 8 8 11 10 12
9 10 9 8 12 12 10 10 10 10 8 9 9 12 10 13
10 11 11 9 13 13 11 11 11 10 9 10 10 13 11 13
11 12 13 10 14 14 12 12 12 11 10 11 11 14 12 14
12 13 14 11 15 15 13 13 12 12 11 12 12 15 12 14
13 15 16 12 16 16 14 14 13 13 11 13 13 16 13 15
14 16 17 13 16 16 14 15 14 14 12 14 13 16 13 15
15 17 18 14 17 17 15 16 15 15 13 15 14 17 14 15
16 18 20 15 18 18 16 17 16 16 13 16 15 18 14 16
17 19 21 15 19 19 17 18 16 17 14 17 16 19 15 16
18 20 22 16 20 20 18 19 17 18 15 18 17 20 16 17
19 21 24 17 21 21 19 20 18 19 15 19 18 21 16 17
20 22 - 18 22 22 20 21 19 19 16 20 18 22 17 18
21 23 - 19 22 22 21 22 20 20 17 21 19 23 17 18
22 24 - 19 23 23 22 23 21 21 17 22 20 24 18 18
23 26 - 20 24 24 23 24 21 22 18 23 21 24 18 19
24 27 - 21 24 25 24 25 22 23 19 24 22 25 19 19
Cor
rect
moi
stur
eco
nten
t
32
III
Met
erre
adin
g(%
moi
stur
eco
nten
t)
Spec
ies
Kem
pas
Lar
anL
arch
,Eur
opea
nL
odge
pole
Pine
Lum
baya
uM
ahog
any,
Afr
ican
Mah
ogan
y,A
mer
ican
Mah
ogan
y,B
razi
lian
Mah
ogan
y,br
ush
Mah
ogan
y,m
iva
Mah
ogan
y,re
dM
ahog
any,
rose
Mah
ogan
y,sa
ntos
Mah
ogan
y,H
ondu
ras
Mah
ogan
y,w
hite
Mak
oré
Mal
as
7 8 8 8 7 8 10 7 - 8 10 10 9 8 7 9 9 7
8 9 8 9 8 9 11 8 - 9 11 11 10 9 7 10 10 8
9 10 9 10 9 10 12 9 - 10 12 12 10 10 8 11 11 9
10 12 10 11 10 11 13 10 10 10 12 13 11 12 9 12 12 9
11 13 11 12 12 12 14 11 10 11 13 14 12 13 10 13 13 10
12 14 11 13 13 12 15 12 11 11 14 15 12 14 11 14 14 11
13 15 12 14 14 13 16 13 12 12 15 16 13 15 12 15 15 12
14 16 13 15 15 14 17 14 13 12 15 17 14 16 13 16 15 12
15 17 14 16 16 15 18 15 14 13 16 18 14 17 14 17 16 13
16 18 14 17 17 15 19 16 15 14 17 19 15 18 15 18 17 14
17 19 15 18 18 16 20 17 15 14 18 20 16 19 16 19 18 15
18 20 16 19 19 17 21 18 16 15 18 21 16 20 17 20 18 15
19 21 17 20 20 18 22 19 17 15 19 22 17 21 18 21 19 16
20 22 17 21 21 19 23 20 18 16 20 23 18 22 19 22 20 17
21 23 18 22 22 19 24 21 19 16 20 24 18 23 19 23 21 18
22 24 18 23 23 20 25 22 20 17 21 24 19 24 20 24 22 19
23 25 19 24 24 21 26 23 21 18 22 25 20 25 21 25 23 19
24 26 19 25 25 22 27 24 22 18 23 26 20 26M
ahog
any,
sout
hern
89
1011
1212
1314
1516
1718
1920
2021
2223 22 26 24 20
Cor
rect
moi
stur
eco
nten
t
33
III
Met
erre
adin
g(%
moi
stur
eco
nten
t)
Spec
ies
Map
le,C
anad
ian
Map
le,Q
ldM
aple
,ros
eM
aple
,sug
arM
arar
ieM
arri
Mat
aiM
eran
tiM
essm
ate
Nut
meg
(Fiji
sour
ce)
Oak
,Am
eric
anre
dO
ak,E
urop
ean
Oak
,New
Gui
nea
Oak
,silk
y,no
rthe
rnO
ak,s
ilky,
red
Oak
,silk
y,so
uthe
rnO
ak,t
ulip
,blu
sh
7 7 10 8 7 10 7 9 7 10 7 7 7 7 8 8 7 7
8 8 10 8 7 11 8 9 8 11 8 8 8 8 8 9 10 11
9 9 11 9 8 11 9 10 9 12 9 9 9 9 9 9 10 12
10 10 12 10 10 12 9 11 10 12 10 11 10 10 10 10 11 12
11 11 13 10 12 13 10 12 11 13 11 12 11 11 11 11 12 13
12 12 14 11 13 14 11 12 12 14 11 13 12 12 12 11 13 14
13 13 15 12 14 14 11 13 13 15 12 14 13 13 13 12 14 15
14 14 16 12 15 15 12 14 14 16 13 15 14 14 14 13 15 16
15 15 17 13 16 16 13 15 13 16 14 16 15 15 15 13 16 16
16 16 18 14 17 17 13 16 16 17 14 17 16 16 16 14 17 17
17 17 18 14 18 18 14 16 17 18 15 18 17 17 17 15 18 18
18 18 19 15 19 18 15 17 18 18 16 18 18 18 17 16 19 19
19 18 20 16 20 19 15 18 19 19 17 20 19 19 18 16 20 20
20 20 21 16 21 20 16 18 20 20 18 21 21 20 19 17 21 21
21 21 22 17 22 21 17 19 21 21 18 22 22 21 20 18 22 22
22 22 23 18 23 21 17 20 22 22 19 23 23 22 21 18 23 23
23 23 24 18 24 22 18 21 23 22 20 21 24 23 22 19 24 24
24 24 24 19 - 23 19 22 24 23 21 25 25 24 23 20 25 25
Cor
rect
moi
stur
eco
nten
t
34
III
Met
erre
adin
g(%
moi
stur
eco
nten
t)
Spec
ies
Oak
,tul
ip,b
row
nO
ak,t
ulip
,red
Oak
,whi
teO
bech
e
Pada
uk,A
fric
anPe
pper
min
t,br
oad-
leav
edPe
pper
min
t,na
rrow
-lea
ved
Pers
imm
on
Pine
,bun
yaPi
ne,C
orsi
can
Pine
,cyp
ress
,whi
tePi
ne,h
oop
Pine
,Huo
nPi
ne,K
ing
Will
iam
7 10 11 6 7 7 9 10 7 10 9 9 10 10 9
8 11 12 7 8 7 10 11 8 11 10 10 11 10 9
9 12 13 8 9 8 11 11 9 12 11 11 11 12 11
10 12 14 9 10 9 12 12 10 12 12 11 12 12 12
11 13 15 10 10 10 13 13 10 13 13 12 13 13 12
12 13 16 11 1 11 14 14 11 14 14 13 14 13 13
13 14 17 12 12 12 15 14 12 14 15 14 15 14 14
14 14 18 13 13 13 16 15 13 15 16 15 16 15 14
15 15 18 14 14 14 17 16 14 16 17 17 17 15 15
16 16 19 15 15 15 18 17 15 16 18 17 17 16 16
17 16 20 16 15 15 19 18 15 17 19 18 18 17 16
18 17 21 17 16 16 20 18 16 18 20 19 19 18 17
19 18 22 18 16 17 21 19 16 18 22 20 20 18 18
20 18 23 18 17 18 22 20 17 19 23 21 21 19 18
21 19 24 19 18 19 23 21 18 20 24 22 22 20 19
22 19 25 20 18 19 24 22 18 21 25 22 22 20 20
23 20 25 21 19 20 25 22 19 21 26 23 23 21 20
24 20 26 22 20 21 26 23 20 22 27 24 24 22 21
Cor
rect
moi
stur
eco
nten
t
35
III
Met
erre
adin
g(%
moi
stur
eco
nten
t)
Spec
ies
Pine
,klin
kiPi
ne,l
ongl
eaf
Pine
,lod
gerp
ole
Pine
,mar
itim
ePi
ne,w
hite
,NZ
Pine
,Par
ana
Pine
,pon
dero
saPi
ne,r
adia
taPi
ne,s
cots
/sho
rtle
afPi
ne,s
lash
Pine
,sug
arPi
ne,w
hite
,wes
tern
Popl
arQ
uand
ong,
silv
er
Red
woo
d
7 7 9 7 10 - 7 7 10 7 8 8 - 7 7 9
8 8 10 9 11 - 8 9 11 9 9 9 8 9 8 9
9 9 11 10 12 - 9 10 11 10 10 10 9 10 9 10
10 10 12 11 12 11 10 11 12 11 11 11 10 11 10 11
11 11 13 12 13 12 11 13 13 12 12 12 11 12 10 12
12 12 14 13 14 12 12 14 14 13 13 13 11 13 11 13
13 13 15 14 15 13 13 15 15 14 14 14 12 14 12 14
14 14 16 15 15 14 14 16 16 15 15 15 13 15 12 15
15 15 17 16 16 15 15 17 17 16 16 16 14 16 13 16
16 16 18 17 17 16 16 18 18 17 17 17 15 17 14 16
17 17 19 18 18 16 16 19 19 18 17 18 16 18 14 17
18 18 20 19 18 17 17 20 20 19 18 20 17 19 15 18
19 19 22 20 19 18 18 21 21 20 19 21 17 20 16 19
20 20 23 21 20 19 19 22 22 21 20 22 18 21 16 20
21 21 24 22 21 19 20 22 24 22 21 23 19 22 17 20
22 22 25 23 21 20 21 23 25 23 22 24 20 23 18 21
23 23 26 24 22 21 22 24 26 24 23 25 21 24 18 22
24 24 27 25 23 22 23 25 27 25 24 26 22 25 19 23
Cor
rect
moi
stur
eco
nten
t
36
III
Met
erre
adin
g(%
moi
stur
eco
nten
t)
Spec
ies
Red
woo
d,E
urop
ean
Ros
aros
aSa
pele
Sass
afra
sSa
ssaf
ras,
sout
hern
Satin
ash,
grey
Satin
ash,
New
Gui
nea
Satin
ash,
rose
Satin
aySa
tinhe
art,
gree
nSe
petir
Sheo
ak,r
iver
Sheo
ak,r
ose
Sheo
ak,W
ASi
lkw
ood,
bolly
7 7 8 9 8 9 8 7 7 7 9 8 8 9 9 9
8 9 9 10 9 10 9 8 7 8 10 9 9 10 10 10
9 10 10 11 10 11 9 8 8 9 10 10 10 11 11 11
10 11 10 12 10 11 10 9 8 10 11 12 10 11 11 11
11 12 11 13 11 12 11 10 9 11 11 13 11 12 12 12
12 13 12 14 12 13 12 11 10 12 12 14 11 13 12 12
13 14 13 15 13 13 13 11 10 13 12 15 12 13 13 13
14 15 13 16 13 14 14 12 11 14 13 16 12 14 14 13
15 16 14 17 14 15 15 13 12 15 13 17 13 14 14 14
16 17 15 18 15 15 16 13 12 16 14 18 14 15 15 14
17 18 15 19 16 16 16 14 13 17 14 20 14 15 16 15
18 19 16 20 16 17 17 15 13 18 15 21 15 16 16 15
19 20 17 22 17 17 18 16 14 19 15 22 16 16 17 16
20 21 18 23 18 18 19 16 15 20 16 23 16 17 18 16
21 22 18 24 18 19 20 17 16 21 16 24 17 18 18 17
22 23 19 25 19 19 21 18 16 22 17 25 17 18 19 17
23 24 - 26 20 20 22 19 - 23 - 26 18 19 20 18
24 25R
osew
ood,
Pata
goni
an8
910
1213
1415
1617
1819
2021
2223
2425
26R
osew
ood,
Tie
te8
910
1213
1415
1617
1819
2021
2223
2425
26 - 27 21 21 23 19 - 24 - 27 - 19 20 18
Cor
rect
moi
stur
eco
nten
t
37
III
Met
erre
adin
g(%
moi
stur
eco
nten
t)
Spec
ies
Silk
woo
d,re
dSi
lkw
ood,
silv
erSp
ruce
,Sitk
aSp
ruce
,wes
tern
whi
teSt
ring
ybar
k,br
own
Stri
ngyb
ark,
Dar
win
Stri
ngyb
ark,
yello
wSy
cam
ore
Syca
mor
e,sa
tinSy
cam
ore,
silv
er
Tallo
ww
ood
Taw
a
Teak
Tin
gle,
red
Tin
gle,
yello
w
7 6 9 7 7 9 8 11 7 9 9 7 9 7 9 9
8 7 10 8 8 10 8 12 7 9 10 8 10 7 10 10
9 7 11 9 10 11 9 13 8 10 10 9 10 8 11 11
10 8 12 11 11 11 10 14 9 11 11 10 11 9 12 12
11 9 12 11 12 12 11 14 10 11 12 11 11 10 13 13
12 10 13 12 13 13 12 15 11 12 12 12 12 11 15 14
13 10 14 13 14 14 13 16 12 12 13 13 12 12 16 15
14 11 15 15 15 15 14 17 13 13 13 14 13 13 17 17
15 12 15 16 16 16 15 18 14 14 14 15 13 14 18 18
16 12 16 17 17 17 15 18 15 14 14 16 14 14 19 19
17 13 17 18 18 18 16 19 15 15 15 17 14 15 21 20
18 14 18 19 19 19 17 20 16 16 16 18 15 15 22 21
19 14 18 20 20 19 18 21 17 16 16 19 15 16 23 22
20 15 19 21 21 20 19 21 18 17 17 20 16 16 24 23
21 16 20 22 21 21 20 22 19 18 17 21 16 17 25 25
22 17 20 23 23 22 21 23 19 18 18 22 17 18 27 26
23 17 21 25 24 23 22 24 20 19 19 23 17 19 28 27
24 18 22 26 25 24 22 24
Tig
erw
ood
1011
1213
1415
1617
1819
2021
2223
2425
262721 20 19 24 18 20
Teak
,Bra
zilia
n8
910
1213
1415
1617
1819
2021
2223
2425
26 29 28
Cor
rect
moi
stur
eco
nten
t
38
III
Met
erre
adin
g(%
moi
stur
eco
nten
t)
Spec
ies
Tota
raTo
urig
a,re
dT
uart
Tur
pent
ine
Vite
x,N
ewG
uine
aW
alnu
t,A
fric
an
Wal
nut,
blus
hW
alnu
t,E
urop
ean
Wal
nut,
New
Gui
nea
Wal
nut,
Qld
Wal
nut,
yello
wW
ando
oW
attle
,hic
ory
Wat
tle,s
ilver
Wes
tern
Hem
lock
Wes
tern
red
spru
ceW
olly
butt
7 8 11 9 8 8 10 10 9 7 9 7 10 8 9 7 7 10
8 9 11 10 9 8 11 11 10 8 10 8 11 9 10 9 9 10
9 10 12 11 10 9 12 11 11 9 11 8 12 10 10 10 10 11
10 10 13 12 11 10 13 12 12 10 12 9 13 11 11 11 11 12
11 11 14 12 12 11 14 12 13 11 13 10 14 11 12 12 12 13
12 12 14 13 13 12 15 13 14 12 14 10 15 12 13 13 13 14
13 12 15 14 14 13 16 14 15 13 15 11 16 13 13 14 14 15
14 13 16 15 15 13 17 14 16 14 16 12 16 13 14 15 15 15
15 14 17 15 16 14 18 15 17 15 17 12 17 14 15 16 16 16
16 14 17 16 17 15 19 16 18 16 18 13 18 14 16 17 17 17
17 15 18 17 18 16 20 16 19 17 19 14 19 15 16 18 18 18
18 16 19 17 19 17 21 17 20 17 20 14 20 16 17 19 19 19
19 16 20 18 20 18 22 18 22 18 22 15 21 16 18 20 20 20
20 17 20 19 21 18 23 18 23 19 23 16 22 17 19 21 21 20
21 18 21 20 22 19 24 19 24 20 24 17 23 18 20 22 22 21
22 18 22 20 23 20 25 19 25 - 25 17 24 18 20 23 23 22
23 19 23 21 24 21 26 20 26 - 25 18 25 19 21 24 24 23
24 19 23 22 24 22 27W
alnu
t,A
mer
ican
Bla
ck8
910
1213
1415
1617
1 819
2021
2223
2425
268
910
1213
1415
1617
1819
2021
2223
2425
26W
alnu
t,B
razi
lian
Wal
nut,
Peru
vian
21 27 - 27 19 25 20 22 25 25 24
Cor
rect
moi
stur
eco
nten
t
78
911
1213
1415
1617
1818
2021
2223
2125
39
III
40
The RH Probe utilises “state of the art” electronictechnology to provide an “easy to use” and accurate methodfor measuring relative humidity, mixing ratio, temperatureand dew point in a wide range of applications such as:-
Heating, ventilation and air conditioning(HVAC) systems.Environmental and building monitoring.Building inspection.Flooring (including ASTM F 2170 In Situ &ASTM F 2420 RH Hood methods)
A typical MRH display with the RH Probe attached is shownon page 13. Pressing the on theinstrument changes the temperature readings from ºC to ºF,the mixing ratio from g/kg (gms) to Grains/Lb (GRN) orvice-versa.
NOTE: When performing Humidity tests on ConcreteFlooring it should be noted that:A): If artificial aids for accelerated drying of concrete arebeing used it is recommended that they be turned off at leastfour days before taking final readings.B): It is important that the installer ensures that the floorcovering is applied at the moisture content and or relativehumidity specified by the manufacturer of the floorcoverings and/or adhesives.
C): It is very important that RH probes are handled with careand protected from harsh environments in order to maintaintheir long-term stability. It is recommended that you do notinsert the RH probe into concrete until the chemical reactionbetween the cement and water has taken place and thedrying process has begun. To achieve this it is recommendedthat you do not insert the probe into the hole in the concreteuntil the moisture content of the concrete has dropped below5% when measured with a Tramex CME4, Tramex CRHor Tramex CMEX. RH probes should not be left enclosed
III
41
in concrete or similar environments at an RH level greaterthan 93% for long periods, in these situations it isrecommended to remove the RH probe and allow the testarea to continue to acclimatise by replacing the stopper inthe hole-liner sleeve.
Each RH probe is factory calibrated using precisionequipment traceable to NIST standards. With reasonablecare in use and storage, RH probe measurements shouldremain within the ±3% specification. RH probe accuracy canbe degraded by exposure to polluted atmospheres such asdust, aggressive chemical vapors, or contaminated wetting.It is thus advisable to periodically check the RH Probeaccuracy by using RH 75 or a similar suitable reference kit.These kits contain a saturated Sodium Chloride salt solutionthat creates a nominal 75% relative humidity within themeasuring cell. The precise relative humidity is temperaturedependent. The RH 75 calibration check is available fromthe manufacturer or the supplier of your MRH meter.
For regular on-site assessment of your MRH in moisturemeasurement mode, a calibration-check box is availablefrom the suppliers of your MRH. Should it be found thatreadings are outside the set tolerances, it is recommendedthat the MRH be returned for re-calibration. Calibration
To carry out a calibration check:-1. Remove cell from sealed plastic bag.2. Remove white stopper plug from cell.3. Insert plastic calibration sleeve into cell as shown in photo on left.4. Remove sleeve stopper plug and fully insert RH probe.5. Place cell/probe in a stable, draft free, temperature
environment, e.g., inside a desk drawer, and leave for at least 2 hours.
6. After 2 hours, connect probe to MRH and measure RH value.7. The RH reading should be 75% ± 3%8. If the value is outside this range,
repeat the test after a further 2 hours.9. If the RH value is still outside specification,
return the RH probe to Tramex for investigation.10. When the calibration check test has been
completed, removeRH probe and sleeve from cell.Fit white stopper plug into cell and seal cell inside
the plastic bag.
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adjustments should not be carried out by anyone other thanTramex or their authorised service provider who will issue acalibration certificate on completion.Requirements for quality management and validationprocedures, such as ISO 9001:2008, have increased the needfor regulation and verification of measuring and testinstruments. It is therefore recommended that calibration ofthe MRH should be checked and certified in accordancewith the standards and/or protocols laid down by yourindustry (usually on an annual basis) by an authorized testprovider. The name of your nearest test provider andestimate of cost is available on request.
The MRH will not detect or measure moisture through anyelectrically conductive materials including metal sheeting orcladding, black EPDM rubber or wet surfaces.
Tramex warrants that this instrument will be free fromdefects and faulty workmanship for a period of one yearfrom date of first purchase.If a fault develops during the warranty period, Tramex will,at its absolute discretion, either repair the defective productwithout charge for the parts and labour, or will provide areplacement in exchange for the defective product returnedto Tramex Ltd.This warranty shall not apply to any defect, failure ordamage caused by improper use or improper or inadequatemaintenance and care.In no event shall Tramex, its agents or distributors be liableto the customer or any other person, company ororganisation for any special, indirect, or consequential lossor damage of any type whatsoever (including, withoutlimitation, loss of business, revenue, profits, data, savings orgoodwill), whether occasioned by the act, breach, omission,default, or negligence of Tramex Ltd., whether or not
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foreseeable, arising howsoever out of or in connection withthe sale of this product including arising out of breach ofcontract, tort, misrepresentation or arising from statute orindemnity.Without prejudice to the above, all other warranties,representations and conditions whether made orally orimplied by circumstances, custom, contract, equity, statuteor common law are hereby excluded, including all termsimplied by Section 13, 14 and 15 of the Sale of Goods Act1893.Warranty claimsA defective product should be returned shipping pre paid,with full description of defect to your supplier or Tramex ataddress shown below.
It is the policy of Tramex to continually improve and updateall its products.We therefore reserve the right to alter the specification ordesign of this instrument without prior notice.
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Tramex LimitedShankill Business CentreShankillCo. DublinIrelandTel: +353 1 239 3224Fax: +353 1 282 7880
Email: [email protected] Site: www.tramex.ie
USA and Canada Tramexc/o Black Hawk Sales Inc.28 Pin Oak DriveLittletonCO 80127Tel: 303 972 7926Fax: 303 972 7106
Email: [email protected] Site: www.tramexltd.com
U.K. Tramex Ltd., Tel: 0870 735 2870
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