GE Protimeter MMS Instruction Manual page 18

When high sub-surface relative readings are obtained in the Search
mode, the user is strongly recommended to quantify these values in
%WME terms by using the Deep Wall Probes in the Measure mode.
If the depth of clearance holes is increased incrementally by a
nominal 0.4 in. (10 mm) at a time, the moisture profile through the
wall can be established.
Item 2: Condensation related moisture problems are common. When
assessing the risk of condensation, or confirming its existence, the
proximity of the actual temperature of the surface under
investigation to the dew point must be established. The T
measurement in CONDENSATOR mode tells the user how many
degrees the temperature of a surface is above or below the dew point.
As many condensation situations are transient, T
be taken in a methodical and regular manner, similar to moisture
meter readings in materials. Ambient RH and temperature values
should also be taken to assess the moisture condition of the room as a
whole. Dwellings and working environments generally have an RH
from 40% to 60%, so there may be cause to investigate environments
that register RH values outside this range.
Item 3: Two hygroscopic salts, chlorides and nitrates, may build up on the
surface of walls where rising dampness or wicking occurs. As
groundwater moves through the wall and migrates to the surface,
salts tend to accumulate where the rate of evaporation of this water is
greatest. The salts themselves are non-conductive, but when mixed
with a small amount of moisture a highly conductive solution is
formed. The presence (or absence) of such salts should therefore be
established when rising dampness is suspected by using the
Protimeter MMS in Measure mode as described. When required, the
Protimeter Salts Analysis Kit (part number BLD4900) can be used to
identify the relative concentrations of nitrates and chlorides.
In summary, effective dampness diagnosis is a process that draws on the
knowledge and expertise of the surveyor. The Protimeter MMS kit enables the
user to investigate moisture levels in materials and environments from various
perspectives that, in turn, permits a more thorough and reliable judgement as
to the cause of dampness related problems.
Protimeter MMS Moisture Measurement System
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readings should
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