Definition Of Dew Point; Assessing Thermal Bridging And Insulation Continuity; Credits - FLIR InfraCAM User Manual

12 – Introduction to building thermography
Figure 12.7 A: Temperature in degrees Fahrenheit; B: Maximum amount of water in gr/ft
A B
86.0 13.30
84.2 12.60
82.4 11.93
80.6 11.29
78.8 10.68
77.0 10.10
75.2 9.54
73.4 9.01
71.6 8.51
69.8 8.03
Example:
The relative humidity of a certain volume of air at a temperature of +30°C (+86°F) is
40 % RH. Amount of water in 1 m
= 30.44 × 0.40 = 12.18 g (187.96 gr).
12.3.7.2
Dew point can be regarded as the temperature at which the humidity in a certain
volume of air will condense as liquid water.
Example:
The relative humidity of a certain volume of air at a temperature of +30°C (+86°F) is
40 % RH. Amount of water in 1 m
= 30.44 × 0.40 = 12.18 g (187.96 gr). In the table above, look up the temperature
for which the amount of water in air is closest to 12.18 g. This would be +14.0°C
(+57.2°F), which is the approximate dew point.
12
12.3.8
12.3.8.1
This Technical Note was produced by a working group including expert thermogra-
phers, and research consultants. Additional consultation with other persons and or-
ganisations results in this document being widely accepted by all sides of industries.
The contents of this Technical Note is reproduced with kind permission from, and
fully copyrighted to, United Kingdom Thermography Association (UKTA).
106
A B
68.0 7.58
66.2 7.14
64.4 6.73
62.6 6.34
60.8 5.97
59.0 5.62
57.2 5.29
55.4 4.97
53.6 4.67
51.8 4.39
3
(35.31 ft

Definition of dew point

3
(35.31 ft

Assessing thermal bridging and insulation continuity

Credits

A B
50.0 4.12
48.2 3.86
46.4 3.62
44.6 3.40
42.8 3.18
41.0 2.98
39.2 2.79
37.4 2.61
35.6 2.44
33.8 2.28
3
) of air at +30°C = 30.44 × Rel Humidity
3
) of air at +30°C = 30.44 × Rel Humidity
Publ. No. 1558299 Rev. a200 – ENGLISH (EN) – February 12, 2007
3 (at sea level)
A B
32.0 2.12
30.2 1.96
28.4 1.81
26.6 1.67
24.8 1.54
23.0. 1.42
21.2 1.31
19.4 1.21
17.6 1.11
15.8 1.02