Dew Point Tables

Oct 12, 2026

Dew point tables explain the dew point as the temperature at which air becomes saturated and water vapour begins to condense on a surface. The document highlights why dew point matters for coating and safety, linking condensation risk to atmospheric aggressivity, humidity, and surface wetness. It further notes that moisture and dew point are critical in metal corrosion and in determining when electrochemical corrosion processes can occur.

LanguageEnglish

CategoryGeneral

FormatPDF

Pages4

Reading Time2 min

AccessFree to download

Dew point definition and importance

Condensation risk and safety margins

Effects of humidity on corrosion and coating curing

Dew point versus relative humidity chart

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oC | MP. | DEW POINT
50% 5 | IN OC
5% 60% | | AT RELA
65% 70 | TIVE HUM
% 75% | | IDITY LIST
80% 85% | | ED
90% | | | | | 16
17 | | 5.6 7
6.5 7 | .0
.9 | 8.3
9.2 | 9.5 10
10.4 11 | .5 11.6
.5 12.5 | | 12.5 13.
13.5 14. | | 5 14.4
5 15.3 | | | | | 18
19
20 | | 7.4 8
8.3 9
9.3 1 | .8
.7
0.7 | 10.2
11.1
12.0 | 11.4 12
12.3 13
13.3 14 | .4 13.5
.4 14.5
.4 15.4 | | 14.5 15.
15.5 18.
16.4 17. | | 4 16.3
4 17.3
4 18.3 | | | | | 21
22
23 | | 10.2 1
11.1 1
12.0 1 | 1.6 12.9
2.5 13.8
3.5 14.8 | | 14.2 15
15.2 16
16.1 17 | .3 16.4
.3 17.4
.2 18.4 | | 17.4 18.
18.4 19.
19.4 20. | | 4 19.3
4 20.3
3 21.3 | | | | | 24
25
26 | | 12.9 1
13.8 1
14.8 1 | 4.4 15.7
5.3 16.7
6.2 17.6 | |
17.0 18 17.9 19
18.8 20 | |
19.3
20.3
21.2 | 20.3 21.
21.3 22.
22.3 23.3

| |

3 22.3
3 23.2 24.2 | | | | | 27
28 | | 15.7 1
16.6 1 | 7.2 18.6
8.1 19.5 | |
19.8 21 20.8 22 | .
.1 22.2
.0 23.2 | | 23.2 24.
24.2 25.2 | | 3 25.2
26.2 | | | | | 29
30 | | 17.5 1
18.4 2 | 9.1
0.0 | 20.5
21.4 |
21.7 22 22.7 23 | .9 24.1
.9 25.1 | | 25.2 26.
26.2 27.2 | | 2 27.2
28.2 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 60 | | | | | | | | | | | | | | | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | | | 01 SP
02 IND | ECIFIERS
USTRIAL | MANUAL | | ANY PRO | | | | | | | | | 03 AD
04 BO | HESION O
LTING GA | F PROTEC
LVANIZED | TIVE COAT STEEL | INGS | | | | | | | | | 05 BU
06 CO
07 CO | RIED GALV
NCRETE D
RROSION | ANIZED SURABILITY MAPPING | TEEL & GALVA | NIZED RE | BAR | | | | | | | | 08 CO
09 CU
10 CU | ST FACTO
STOM CO
T EDGE P | RS FOR H
ATING PAC
ROTECTIO | OT DIP GAKAGES N | LVANIZED | COATINGS | | | | | | | | 11 DE
12 ILL
13 DEW | SIGNING F
USTRATED POINT T | OR GALVA
GUIDE TO
ABLES | NIZING DESIGN | FOR GALV | ANIZI

FAQs

What is the dew point?

The dew point is the temperature at which air becomes saturated with water vapour and condensation can begin.

Why are dew point tables important for coating work?

They help assess whether condensation and surface wetness may occur, which affects coating quality and related safety conditions.

How does relative humidity relate to dew point and condensation?

As relative humidity increases, the dew point temperature rises, making it more likely that condensation will form when surfaces are cooler than the dew point.

Oct 12, 2026

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